Tire Repair, Pressures,
Sizes, Rims, Studding, Vibration/Thrumming, Mudflaps, Repairing Tube type and Tubeless type tires. ETC.
© Copyright, 2013, R. Fleischer
Article # 54....section12
The items shown in this article are SOME of the things that SOME folks carry along with them on their rides/tours; or, use in the home garage.
How MOST tire punctures/flats occur (maybe!!):
I am not sure of the full correctness of the commonly held belief that the front tire
"sets up" road debris for rear tire punctures. I think
it quite possible, and thus it would be a reason the rear tire always gets more punctures than the front. I think the MAIN reason is because the rear tire is the POWER applier, and hence produces MUCH more force to things in the road. I have seen arguments that the use of a mud-flap on the front will reduce punctures. THAT may also be correct. A few think that a mud-flap on the FRONT OF THE REAR FENDER also helps SOME, if it sticks down enough. That is not very easy to accomplish properly on some bikes, as the rear fender is not usually part of the wheel unit. I think both flaps MAY WELL HELP.
I have found nothing but anecdotes; no definitive testing on how/why/details
punctures occur. If there is such testing, I'd be interested in looking at it. I
suspect that more than one tire company has done testing in this area; but have
not looked in some years for it. I once tried to find out, from two tire
manufacturer's, and did not get much useable information back from them.
It may be a combination of things, and that is what I believe. Various discussions and arguments put forth
(some by me!) have included weight; the high pressure-point contact of the rear tire when the motorcycle is accelerating; the fact that the rear tire slips a lot, even in cruise, even when not accelerating; etc. My own belief is that punctures primarily are a combination of the front tire 'sometimes picking up debris', but probably (??) the phenomena is PRIMARILY the driving and also when accelerating forces at the point barely ahead of the major contact area, that is responsible for flat tires. As you ride, power-on just to maintain speed, and worse when accelerating, this causes the rear tire tread to deform, and that helps to strongly pick up the debris and force it into the tire. A factor with this particular idea is that low tire pressures probably increase the likelihood of flats, and many do not check tire pressures regularly.
Until I get some sort of definitive answers/replies from motorcycle tire manufacturer's who have actually done testing, I leave my speculations...or at least ideas.... for you.
Meanwhile, don't ride in the middle of the lane, don't ride on shoulders of the
lane, and keep your tires inflated...and INSPECT THEM regularly. A fair
amount of flats occur from nails, etc., that have been in the tire for some
time. Install mud flaps, at least at the rear of the front fender.
There is something hardly ever said, that is favorable for some tires (and, any others similarly constructed): A tubeless tire that does NOT use steel strands in the tread is more likely to have a LASTING on-road repair from use of sticky strings or internal patch, or certain types of external plugs. This is particularly so if you are using such as the Stop'nGo slippery mushroom type of plugs, which require a lot of reaming into punctures in steel belted and steel ply tires. The Avon Roadriders, as ONE example, do NOT have steel plies. Conversely, that makes them POSSIBLY more conducive to punctures.
Some preliminary information:
Getting a rear wheel out, various methods:
(a) Bike on center-stand at curb, rear wheel hanging over curb.
(b) Bike on center-stand. Tie center-stand to front exhaust crossover pipe. SECURELY.
Use extra strong bungees. USE TWO to be safely sure of no problems!
Remove front wheel. You will have to undo any disc brake caliper(s) that prevents the wheel from
removal, hang via a bungee, NOT by the hose.
Put gloves on ground. Slowly tilt bike forward, so forks rest on the gloves.
You now have the rear end of the bike WAY up in the air, and PLENTY of room to work.
(c) You may find that the wheel does not come out, even on an angle, unless the front end is lowered,
or the center-stand is used with a board underneath it. This all varies with model, and if you have
stock size tires and stock center-stand, etc. If you are careful, you can remove the wheel all by
yourself by tilting the bike a bit to the right, while getting the wheel out. It helps if the tire is fully deflated.
(d) If you have a Reynolds Ride-Off center-stand, you may need to put a board under the center-stand.
This is particularly so if you have an oversize front tire.
If you have tubeless tires, you probably will repair the flat tire temporarily with a plug of some sort. You could also consider removing the wheel and inserting a tube. An internal plug and patch on the inside of the tire is the proper permanent repair. Use your best judgment on this. Sidewall repairs almost never hold up. You are not really suppose to ride at any speed with an external plug. Steel cords, in tires containing them, can cut inside or outside plugs, over time/miles.
work, such as repairing a tube, or installing an INternal
patch/plug, breaking the bead is necessary, and OFTEN NOT
FUN AT ALL. You must have the tire totally deflated.
You can try the weight on one side of the center-stand; or
side-stand; I think those things are iffy for most, and I prefer a tire bead breaker.
You CAN carry a multi-piece bead-breaker, that assembles easily, and usable by the side of the road. I suggest the following product, and it is a LOT better than the modified C-clamp that I used to carry, all-things-considered:
Tubes: the purpose of the single outside valve stem nut is to help with installation of the new tube. After installing the new tube &
inflating the tube/tire (making sure the stem is sticking straight, not angularly out), the nut can be thrown into the junk box, or thrown away,
or moved up against the cap. I never throw anything away!...unless totally, forever, worthless! Just do NOT have that nut down against the rim. If it is against the rim, & if the tire should shift
on the rim during a serious flat situation, the tire could try to
rotate the tube. Having the nut at the rim does not allow
for ANY tire/tube
Some folks have modified the 8 mm hole in the snowflake tube type rims, to 11.5 mm, and modified the inside area too, so that larger tubeless stems can be fitted for using tubeless tires without running tubes. Flattening the inside of the rim at the hole area by machining may be needed. There are also metal stem types available that fit the smaller original hole, but definitely need a flat inner surface, and I think that type are preferable. BMW and others sell them.
If you have a hole size conversion involving a larger hole, and then revert to TUBES, do NOT use RUBBER to seal the inside, use a metal washer, shaped properly. Use of rubber could cause the tube to not eliminate trapped air between the tube and tire, causing chaffing of the tube. SOME folks have cut off a 'rubber doughnut' by modifying an old car-type tubeless rubber stem. They then use the rubber piece to seal the m/c tube at the rim, with a washer, and nut. This works, but keep in mind all caveats.
Ultimately, anything done besides the original stock method means you are on your own, safety-wise and performance-wise.
REAL tire talc (no oils in it) and REAL tire vegetable based lubricant (thin it per instructions) are available from tire distributors and other places. You might want to obtain some 6 or 8+ ounce flip-tip plastic bottles like used for certain hair and other products, and have some talc in one, some thinned tire lubricant in the other, and keep them on your bike with your big C-clamp or beadbreaker or whatever you use to break the bead from the rim. I keep a spark plug hole type of compressor adapter, patches, spare rear tube (front one too on LONG tours) on the bike. Some may want to use the guts, modified slightly, of one of those cheap CHEAP 12 volt compressors sold at WalMart, etc. They DO work just fine. Frankly, I LOVE those modified compressors...commercial versions using the same Chinese pump are available from bike shops, etc. at a considerably higher price.
ALWAYS replace tubes when replacing tube-containing tires. SOME say to never patch a tube, only use new tubes. I have done both, but replacing a tube anytime the tire is demounted is probably the safest thing to do. The best tubes are natural rubber based, and these resist long tears/rips better, but they also are slightly porous, so they leak, although very slowly. Another good reason to keep an accurate tire pressure gauge in your tank-bag, or wherever on the bike. I recommend you NOT use super-thick competition tubes. There ARE several reasons to replace a tube when replacing a tire, REAL REASONS, including a used tube being weakened by use, and it will NOT fit those weakened areas into the same 'grooves', ETC., that it did on the first tire.....thus, INCREASING the chances of having a tube failure. That type of tube failure is USUALLY NOT REPAIRABLE.
Almost all tires marked as TUBELESS are actually OK to use with tubes. If not sure, ask your tire distributor, although many motorcycle places that sell tires know almost nothing about the finer details. This generality about tubeless usage is NOT necessarily true for radial tires. Yes...there are now some radial tires designed for motorcycles, even some in sizes that will fit your Airhead. Some are designed specifically for classic bikes.
NOTE that tubeless tires containing tubes should be speed limited...to less than the tire rating. The rule of thumb is to reduce the speed rating by one position. This is because adding a tube causes more heat from flexing. You also can expect tread life to decrease. Some have run tube type rims with tube-type tires, that seem to be inside-sealed well enough by the tire maker, to not leak, without tubes being used. I have some preliminary reports that tires are getting better mileage than they did with tubes. You are on your own if you do this sort of thing.
While on the subject of tire ratings: It is not commonly known that H rated tires MAY last longer at reasonable speeds and loads, as compared to V and higher rated tires. This is especially so with the same make and model. Sometimes this is purely the result of the lower rated tire having DEEPER tread! Deeper tread squirms more, and generates more heat, so for higher speed rated tires, manufacturer's may well reduce the depth of the tread. So you MIGHT have the situation of purchasing a high speed rated tire for whatever reason (not speed!), and find out it costs more and lasts less!
Note also that larger tires will change the handling of your bike, you may or may not like the difference. You may or may not even notice the difference. In some cases a larger front tire in a fast handling type, the Metzeler ME33 is an example here, will revert to more stock-like handling, but last longer, and handle better when pushed hard, than the smaller size. Improvement by using a slightly larger tire is NOT a universal thing to be expected!
DO NOT expect more 'grip' from a larger tire...that does not happen, mathematics and testing proves it.
For the rear tire, increasing the size may well help with load carrying ability of the bike, but going too far may cause the rear end to effectively change the front end handling too much for your liking.
Some early Airhead front fender braces do not allow for wider than stock size tires, and a later brace may work. This is a COMMON modification.
BMW has shipped tire rims with rim
widths from 1.85 to 2.75 inches for the tube-type Airheads.
Some tires are too wide for fitting, safely, to those rims, and
the tire might have a rolling tendency in hard
cornering. Don't try to measure a tire rim, there is not a quite specific place you will see, for doing that. Don't believe me?....then, next time you remove a tire, look on the rim for the size...and then try to figure out just where the measurements were taken.
tire may not fit the rear
swing arm. A spacer may be required (BMW does sell them for this purpose).
On the Airheads that specified a 4.00-18" rear tire, generally a 110 rear tire will fit, 120 may or may not, and the same for 100 on the front.
Tires expand in WIDTH as speed rises.
GENERALLY speaking, front
tires of 90 or 100 section or 3.25 or 3.50 are quite usable (handling will change somewhat) with
rear tires of 4.00, 110 and even 120 section, on all the earlier Airheads that used 3.25 front and 4.00 rear. SOME 120 tires
are too wide to fit without rubbing. Often the rubbing
occurs only at high speeds. The 10.7 mm
wide spacer (stock is 9.2 mm) used at the right side of the rear
wheel, part number 36-31-2-301-737, is usually
not needed on 1981 and later twin shock models, when using the
oversize 120-90 x 18 oversize rear tire; but SOME 1981+ DO
REQUIRE IT. The 110-90 x 18 rear tire
fits most Airheads. Frankly, unless you have real reasons, such as very
high loads, the 110 size tire is likely the way to
go unless you use the stock 4.00", which works fine. Rear tires usually must be fully deflated, and messed a bit with, to remove or
replace over the brake drum rear ends, and sometimes with the
disc brake rear ends, even though the caliper can be moved out of
the way. It can be helpful
to cut the rear fender sides on a smooth curving angle, from the
license plate area up and forward, to help tire removal. Those with /2 bikes with hinged rear fender may smile.
Comments about the 129-90 x 18 tire rubbing the swing arm do NOT apply to the late model Monoshock RS and RT Airheads, after all, those bikes were designed for that size tire (they use 2.5" rims, not 2.75" rims, like the twin-shock Airheads do for the older RS and RT).
The 120-90/18 size tire will fit many of the late 70's-to 1984
Airheads. The original size was, of course, 4.00-18. Models from 1981 to 1984 generally, with exceptions!.... will not require that the right side
rear wheel spacer be changed (original was 9.2 mm wide, the wider
one is 10.7 mm and is part number 36-31-2-301-737) if you use a 110 tire, but nearly always WILL with 120. Models
before 1981 probably will require you to change this spacer to
that number for even 110 size. This centralizes the tire in the swing arm better,
to avoid the tire rubbing the swing arm, especially at high speeds. The 120-90 size tire
works best on the wider 2.75 inch rim used on the RS/RT models
(typically 2.75 inch marked rim or "C" on disc brake
models). But, that brings the tire closer to rubbing.
The 120 tire will work on the 2.50 rim on the drum brake models. I do recommend that you use the stock size tire, or use a 110, instead of a 120, as the 110 is easier to remove the wheel when needed.
For instances of tire interference, at rest or at speed, the 'disc brake stay' can be easily offset, and a washer used between disc casting holder and the left side of the wheel. It may well be best to just use a 110/90 size tire, only a FEW 110 are too wide to fit all the Airheads. There ARE some 4.00-18 tires that will not fit the rear twin-shock swing arms, these are usually Enduro type tires; but often can be made to fit by using a wider top hat spacer of some sort on the right side of the rear wheel, that is even wider than the -737 spacer mentioned above. There IS a wider spacer available, you will find information in the following article: http://bmwmotorcycletech.info/wheels.htm
On the front, the stock
3.25-19 tire can be substituted with a 90/90 or 3.50 or a
100/90. SOME oversize front tires will not fit due to
fender/fork brace interference (later braces were wider, and can
be fitted), but other airhead braces or
modifications can be used. Different tires MIGHT require
SLIGHTLY different tire pressures, and will handle a bit
differently. The large size tires generally give a more stable
feeling, but are not quite as quick handling. Remember that
tire profile varies with size. You may not notice the
difference except in longer wear, but there is also the situation where the tire wear, especially the rear, flattens considerably. A flattened REAR tire is THE most COMMON cause of high speed INstabilities...REALLY!!
In some cases, such as with a Metzeler ME33 tire, which is quicker handling due to design, going to an oversize front tire seems to make the handling exceptionally nice. After 1984, in general, the stock size tires seem to work best. NOTE that in the 110 and 120 size rear tires, the maximum width varies a lot between manufacturer's. Some Continental's in both 110 and 120 are particularly wide....TOO WIDE. It is probably better to use a 110, unless you know and for some reason insist on a 120, and know the 120 will fit OK, and not rub the driveshaft tube, nor perhaps the disc brake stay....at speeds of 85 mph this has been known to happen, even on later, 1981+ bikes not needing the wider right side spacer. If you have to move the rear wheel to the left with a wider right side spacer, you MIGHT, in some situations, need a flat washer between the disc brake caliper cast holder, and the left side top hat spacer, and might have to play with the brake stay a bit. This is very simple to do. Be sure to read NOTE 27, below.
NOTE!....the classic BMW handling is had ONLY with the exact original brands, sizes and styles of tires.
Tires are designed to be
operated at a temperature of around 250 degrees Fahrenheit, at
the contact point, quite a bit
cooler up the sidewall. Peak spot tire temperatures
cool off VERY RAPIDLY after you
stop. Tires have many ratings, and motorcycle
tires are now becoming better marked, with the type of ratings
that the car tire manufacturer's have had to put on their
sidewalls for some years. There is a letter code for load, a
letter code for speed rating....and some are coding for
wear. There is, of course, a coding for the week and year
You may be surprised to learn that the difference between the tires of various speed ratings is SOMETIMES just a matter of tread depth! All else being the same, you obviously will get more wear from a deeper tread, IF you do not ride much at high speeds where the heat buildup in the more squirmy deeper tread takes over. As a GENERAL rule, if you plan on purchasing a tire, getting a tire rated for your particular driving speeds is more likely to get you a longer-wearing tire. Tire heat kills tires. Heavy loads and hot tarmac in hot weather means less tire life. Deep tread...all other factors kept the same...means more heat. High speed means LOTS more heat. S rated tires are OK for occasional spurts to 112mph; H for 130; V for over 130; and the crotch rockets use Z tires for over 149 mph. It is NOT UNUSUAL to purchase a S or H rated tire instead of a V rated tire, and get LOTS more miles before it wears out...just pay attention to your speed.....and I am talking here about actual speed, and not the maximum the tire is rated at.
Repeating: For serious work, such as repairing a tube, or installing an INternal patch/plug, breaking the bead is necessary, and OFTEN NOT FUN AT ALL. You must have the tire totally deflated. You can try the weight on one side of the center-stand; or side-stand; I think those things are iffy for most, and I prefer a tire bead breaker.
You CAN carry a multi-piece bead-breaker, that assembles easily, and usable by the side of the road. I suggest the following product, and it is a LOT better than the modified C-clamp that I used to carry, all-things-considered:
Removal and replacement of tires is VASTLY easier if the old and new items are placed in hot sunlight and allowed to heat up considerably. It is very helpful to have THREE tire irons, two can be the standard shorter ones from BMW, and one should be the longer available BMW one. Tire lubricant is a MUST.
pry on wheels with the discs laying on the ground...discs must NOT
have pressure placed sideways on them. Gasoline is
NOT an appropriate tire lubricant, and neither is common soap. REAL tire lubricant is a vegetable product, made from FLAX, and is water soluble.
Whether or not tire balancing is any big help, meaning worth doing, is debatable. It certainly is worth the effort and cost if the assembled wheel/tire is quite far out of balance. It almost always is helpful for high speeds. Those who do a lot of miles and do their own tire work may want to invest in a tire balancer. Some no-cost one's can be built, and one of many such types is described on the airheads.org website, but something like the Telefix balancer is worth the money. The tire balance mark, usually a color dot, goes next to the valve stem. If two dots, usually the red is the balance point. There are 3 hole, 4 and 5 hole adaptors available for the Telefix balancing stand for the single rear shock airheads and K bikes. Here is an edited version of something I posted to the IBMWR.org tech list:
Anton Largiader put a page on his website http://largiader.com/balancer/ discussing SOME of the various balancing methods, applicable to K and Airheads too, and there is certainly even more information available in the ibmwr.org archives and other articles you could find. Anton's site has dimensions for some adapters, etc. You can also purchase balancing equipment such as a stand, a round 'axle' (and cones for Airhead jobs), and an adaptor that fits 3, 4, and 5 bolt wheels. I think, considering what dealers charge to install and then balance tires, that a proper balancing stand will pay for itself rather soon if you ride much. There are some simple methods using string, etc., that work, but in my experience they are not as good. I have used a motorcycle type high speed balancer in my BMW shop, but found that it did not work much faster, nor was it any better in actual on-the-road tests, at least for road speeds, as the static Telefix stand type. A long time ago, Harbor Freight sold an adaptor for use on its own balancing stand, applicable to other stands too, but the adaptor is NO LONGER available from them; it was also a bit crude in the hole threading, but quite usable. For the curious, in case they find one someplace, heck, even at an old Harbor Freight store, the adaptor was 98490, for 98488 stand, and the adaptor was 3-1/2" in diameter, 1-3/4" high, and had 8 each 1/2" mounting holes, so spaced to fit most all of the wheels. The center hole was smaller than the Telefix adaptor (the Telefix used a larger rod as axle), but the hole diameter could be changed on a lathe to fit whatever size "axle" you use with your particular balancing stand. Note also that the bolts used with the Harbor Freight adaptor had the cones pressed onto the shank tightly. Two additional threaded holes were in the Harbor freight tool, enabling a bit more versatility for various wheels (3, 4, 5 holes). The Telefix, part number 65.10.01.12, was a nicer-made item than the Chinese-made Harbor Freight adaptor, as you might expect; but fit only the older 3 and 4 bolt wheels.
For Classic K bikes, and the Monoshock and
Paralever Airheads, I have, for a long time now, used a Telefix type of
stand and an adapter that fits the wheel. I have a thinner "axle" with
cones, for use on the Airheads that are twin-shock type. One thing seldom
said is anything about the NEED for balancing wheels/tires. Most motorcycle
tires seem to come relatively well-balanced. Once in awhile there is one
that is quite far off. HOWEVER, seldom do I have to go over 30 grams of
balancing weights. In only a few instances over the years have I been able
to detect a difference, after balancing. My testing was on a very smooth
road, at slowly increasing speed, noting where vibration is, and is not. I
would also do sudden braking at various places I felt any vibration (or
HEARD anything, like thrumming), as the braking can bring on an oscillation
that might not be felt otherwise. I just can't flat out tell everyone that
they must balance wheels and tires. My testing on a number of various bikes
and tires, tubed and not, just does not give answers that are definitive,
yes or no, on balancing. SO.....I think that for most folks, whether or not
to balance the wheels and tires, is not all that cut and dried.
Tires MUST be mounted concentrically. Tires are manufactured with a concentric ridge line near the bead, on both sides of the tire (check both!) so you can easily see if there is equal spacing all around, using the rim edge as a guide versus that concentric tire ridge line. It is a PIA to have to demount the tire if it is not concentric and the most common cause for that is failure to use a lot of proper tire lubricant during assembly, with a secondary cause being too slow of an inflation.....I will get into THAT later in this article. Wet the lubricant or add more if it starts to dry out. When you are done, wash the tire. A new tire should be VERY thoroughly washed with common soap or dish detergent mixture, and hosed off really well. I use a fairly stiff brush. NEVER ride hard, especially in cornering, on a brand new tire, rather, allow 50 miles or so.
It was not all that long ago that tire manufacturer's generally did not want you using over perhaps 50 psi to seat the bead. Most will now say a maximum of 50% over the maximum pressure molded into the sidewall. Even with lots of tire lubricant, I never go over 60 psi. Going higher than 60 CAN BE QUITE
dangerous, although BMW themselves allowed 67 psi in a SI bulletin, so be careful, and use safety equipment, and don't go over 60 psi! Use LOTS of tire lubricant on the tire bead..... that must be on a CLEANED AND SMOOTH rim. Many a time the tire will continue to move slowly upon the rim, seating itself concentrically, after several minutes of sitting there in the sun, well-lubed, inflated....so be patient, and ..again...the use of proper tire lube is a BIG help (flow the stuff onto the bead during the initial assembly & during the inflationing). Rarely one must demount and remount a tire.
TUBE tires: Once the tire is fully inflated, and the ridge lines look concentric on both sides of the rim, & the tire is fully seated at the bead of course, it is a good idea on tube-containing tires to THEN fully deflate the tire (it will not come off the bead-rim), bounce it a bit (upright, turning it and bouncing a few times in different spots), and then re-inflate it to NORMAL pressure; or, to maybe 2 or 3 pounds extra, to allow for settling-in over the next day or so. ONE of the reasons you got your hands full of tire talc and rubbed it all over the tube outer surface and the inside of the tire, is because bouncing, deflated, will tend to let any tube irregularities inside smooth out, and then you can refill with compressed air.
HINT/SECRET: Many a
person has tried to get a tire, properly located in the middle of
the rim, to fully seat to the rim and EVENLY all around during
inflation without success, even after lots of real tire
lubricant, and even with the tire sitting in the sun.
A REAL secret is to do two more things,
right off the bat. First, the compressor must have a
substantial tank, 5 gallons being fine, 2 or 3 might be
OK...........and it should be filled to 100 to 125 psi, or
whatever your compressor can do over 100/125. Secondly, it
is critical that the air chuck NOT HAVE THE CENTER PIN...you need
to remove it! That allows a FAST flow of air from the
chuck. The second thing to do that is even more important
to ensure a FAST flow of air, and that is to REMOVE THE TIRE/TUBE VALVE
CORE. Doing these things with a well-lubricated tire,
will ensure the tire snaps into full concentricity NICELY!
You will have to hold the pin-less chuck against the tire stem
while you open the valve on the compressor, or otherwise turn on
the air. It is the SPEED at which you inflate that is so
important (assuming a lubricated hot tire). Having the tire and wheel in
the sun, and thus HOT, is a BIG HELP.
HINT: The heaviest part of a snowflake wheel is/may be marked near the rim with a CIRCULAR STAMP. Put that marked spot, which is the heaviest point of the wheel balancing, next to the mark on your tire, which is the lightest point on the tire balancing.
For SPOKED WIRE WHEELS, the tire mark goes next to the rim valve hole.
Airheads CAN use the spark-plug hole type of air compressor, but this is a very slow fill, and may not work with new tires, and some used ones. Any possible influx of gas mixture from the carburetor is quite minimal, as these devices use an intake port in the adapter itself. However, since ANY gasoline vapor will rot rubber, at your earliest convenience deflate fully and re-inflate using fresh air. You might have problems inflating with any air source other than a shop compressor. But, you will have a good shot at it with any air source.
The original BMW wheel weights of the snap-in-place type are still available, as are the clips to hold them to the rim. I prefer these to the glue-on/adhesive types, but the preference is not an overwhelming one. Only certain sizes are still available, and this information is, of course, subject to change.
36-31-1-235-625 5 gram
-626 10 gram
-627 20 gram
-628 30 gram
-240-152 15 gram
-153 25 gram
36-11-2-227-943: 5 & 10 gram segments on a strip, self-stick. Originally were for R1200C. Work fine on others.
The clip is 36-31-1-235-632
NEVER EVER work on a wheel...especially with tire irons, with a disc lying on the ground. Support the wheel (tire actually) on 2 x 4's, or use a lidless old oil or grease drum, etc. Repeating a prior caution here, NEVER hang the disc brake calipers by their rubber hoses, you can seriously damage the inside plastic tubing, which has thin walls and is easily damaged.
Brand-new tires need to be cleaned as mentioned earlier herein, AND need to be run 50 or more miles to break them in. Do NOT try tight pushy turns and anything but modest speeds until the tires ARE broken-in. Ride with increasingly larger angles. However, if properly washed....and roughed up with a steel brush...they are more likely to be immediately usable...if done properly. Another way of helping to
break-in brand-new tires...or at least speeding the
process....is to scrub them, including the depth of the tread,
sidewalls, etc., with an old-fashioned bristle-type floor
scrubbing brush, using hot water and detergent, then rinse off.
NOTE!....no matter how you try to speed up the breaking-in
process, the tire will need some riding to warm up the tread and
properly scrub-in and treat the rubber from the heat generated at
the surface contact. Tire break-in is MORE than just scrubbing off mould-release chemicals.
It can be very dangerous to not wash the tire lubricant off before riding, if you happen to ride through some water....the tire can get very slippery, suddenly, and much more than you might expect.
Failure to have a valve CAP on the valve stem CAN cause you to loose air at VERY high speeds, as centripetal force allows the center part to release air (the spring might not be strong enough to prevent that). There ARE high speed Schrader valves available.
Tire Tools, etc.:
71-11-1-237-855 SHORT tire iron, was replaced by
-871 which is the longer one. I prefer my tool kit to
have TWO short, ONE long. I have been told that BMW discontinued the short
irons. In that instance, I'd purchase and carry THREE long ones. There are
aftermarket tire irons available that are quite good.
Tire repair kit:
Type depends on
whether or not you have tubes in your tires. While you WILL want to
carry a tire repair kit, I recommend against CO2 bottles (ANY size). I HATE those
CO2 cylinders; seldom enough of them with you, and they are EXPENSIVE in actual use.
You probably will find them to be a PIA in actual use, and it is easy to not have enough of
them along, or have to re-inflate, etc. They typically come in 16 & 45 gram sizes. You
will need several, no matter the size. FAR better is a very small 12 volt compressor,
Important is something to de-bead the tire. I have made tools for this from C-clamps with
welded curved pieces on the anvils. Probably better are commercial types of strong light
plastic that are cleverly designed, others are metal and/or massive. One that folds up and
comes apart, and stores nicely, and does more than just bead breaking, in fact it INCLUDES
the tire irons, ETC., is this one, & you may well want to look into it:
Just what you get is up to you. There are some complete kits from various manufacturers,
some might include tire irons, patches/plugs, glue, a cylinder (via spark plug hole) operated air
compressor, & they work fine. You can purchase, very cheaply, under $20, a very
small 12 volt electric compressor; remove the innards including the fan, make a plug for it
to fit your auxiliary jack....or alligator clips to go directly to the battery. BOTH of these
types of compressors...spark plug hole...or electric... are FAR better to have than the
near-worthless BMW hand pump that fit on the rear frame. The electric compressors
are also available for nearly $80, mounted in a modest sized can/box. I think them a
waste of money; but YOU MIGHT NOT, and the BestRestProducts.com is a good one.
But, you can purchase the small low-cost compressors at such as WalMart, and if you want
to you can then remove and toss the case. WalMart also likely has really small
cased versions that need no modifications except the correct BMW accessory plug (if
you want that). Coleman also sells a small compressor that does not need the case
removed. For some other ideas on tire repairs....see: http://www.stopngo.com
StopnGo plugs don't work exceptionally
well with steel corded tires, but if
the hole really well on those tires, you can use them, but be prepared to replace a
plug on steel corded tires if on a long trip.
Be sure that if you use the cylinder spark plug
hole style of compressor, the compressor
hose is long enough.
Many BMW airhead motorcycle riders have never repaired a flat tire, nor have they ever changed a
tire. Many have never seriously considered the consequences of having a flat while
on the road; especially if out of cell-phone coverage.
However...many do their own tire repairs, changes, balancing, and wheel bearing service. A LOT of $$ can be saved by doing your own servicing. Knowing it was done correctly is a big added plus.
In the middle area of the photo below is my own modified C-clamp tire
bead-breaker, note the welded-on shaped plates on the jaws/anvils.
The welded-on plates are shaped on one edge of each to match the circular portion of
the wheel rim, so as to have good wide contact with the tire bead at the rim
area. This particular C-clamp has been lightened a bit by drilling holes
in it. This
type of modified C-clamp could be taken along with you on your rides.
Those with TUBELESS tires NOT containing tubes normally do NOT take any type of bead-breaker on rides....but you may want to take along some sort of strap or rope that fits around the circumference of the tire, in case of bead seating problems during trying to re-inflate, if the bead became unseated. THAT usually does NOT happen.
The lower right area
has a weighty and
heavy duty tire bead
breaker. You'd likely NOT take this one on the bike due to its weight,
which is MUCH higher than it looks... but
it is OK for the home shop that does occasional tire work. For serious
work, such as repairing a tube, or installing an INternal
patch/plug, breaking the bead is necessary, and OFTEN NOT
FUN AT ALL. You must have the tire totally deflated.
You can try the weight on one side of the center-stand; or
side-stand; I think those things are iffy for most, and I prefer a tire bead breaker.
You CAN carry a multi-piece bead-breaker, that assembles easily, and usable by the side of the road. I suggest the following product, and it is a LOT better than the modified C-clamp that I used to carry, all-things-considered:
Just in front of it is a modified wrench to operate the nut of the C-clamp bead-breaker, although any common open-end wrench would do. There are many versions of bead-breakers for motorcyclists; the one shown here is very heavy. There are some plastic types that are much lighter, and rather clever. There is another type of bead-breaker, for home/shop use, it is shown in a photo somewhat down this article.
NOTE that some folks use one side of the center-stand to break the bead area, but I have never liked that method. If it works for YOU, then you need NO tire bead breaker.
Please keep in mind that putting pressure on a brake disc and disc carrier is a VERY BAD thing to do, you could, and are LIKELY-TO, warp the disc carrier permanently. If you plan to use the centerstand, keep that in mind, and perhaps carry a piece of wood to keep the disc off the ground.
Fix-A-Flat (or similar brand of goo like Slime) is NOT overly practical, and perhaps should NOT NORMALLY be used. These sometimes work on tube tires, but may work better on tubeLESS tires. Fix-A-Flat and similar stuff makes a mess inside the tube/tire/wheel, OFTEN does NOT work (particularly tubed tires), often prevents a patch from sticking if you are forced to try that later.....and if the stuff does work, it often fails shortly thereafter. One should NEVER let a dealership repair your tire later on without first telling them that you installed that stuff. You will NOT like using solvents and rags to clean out your wheel. Most dealerships will NOT be happy finding out that your tire/tube/wheel has that messy stuff in it. Cleaning it out takes time. Time is money...out of YOUR pocket. SOME do carry these cans of pressurized goo and have had decent results. It DOES give added protection if you are doing a tubeless repair.
At the lower front is a common patch kit for a TUBE-type tire. The patch kit contains patches AND A SMALL TUBE OF GLUE. BE SURE you check your glue tube now and then....even if has never been punctured for use, they have been known to dry out. Some folks replace those glue tubes yearly. Others, LIKE ME, purchase a larger container, usually a small metal can with a brush inside the screw top, and check it every year.
I have not shown a kit for tube-LESS tires....see information later in this article.
At the top middle area is a package containing a new spare
inner-tube. For most bikes with not hugely different front-rear sized
tires you can use a front or rear tube at front or rear in an emergency.
It is usually OK to carry just a spare rear tube, rather than a front tube or
both. Also in this photo is an old pill bottle that contains real tire talc (REAL
tire talc contains no
oils that rot tubes); needed for tube type repairs. To its right
is a plastic squeeze bottle with flip lid; one can use any sort of these
flip lid plastic bottles, such as from hair styling products, and this
particular bottle is partially filled with REAL tire lubricant liquid, made
from properly water-thinned concentrate. Some use thinned soap,
I vastly prefer
REAL tire lubricant, which actually is 'flaxsoap', which is not a soap as you
would normally think of soap. Auto-parts stores carry real tire
lubricant in tubs (thin per the tub-printed information) ...one tub will last
several lifetimes for you and several friends; so share your 5 pound tub with your buddies.
Note the electric air pump with hose and electrical cord (I removed and tossed the original large plastic case before taking this photo). These are available very cheaply, often much less than $20, from such as Wal-Mart, etc. The large outer plastic case is removed, and the small fan removed by cutting the shaft with a Dremel or similar tool, and either alligator clips as shown or perhaps a BMW accessory plug attached at the other end. The current drain from the battery is fairly low for this item. Some of these pumps have air pressure gauges which can be utilized, or not. Motorcycle batteries ARE capable of running these small electric compressors to fill quite a few tires....and still start the engine. These cheap little Chinese compressors also hold up better than you may think. Some folks are packaging these tiny piston compressors in their own metal box, and selling the boxed compressor for $$$.These electric pumps are now available in a SMALL package; previously they were not....so see further down this article.
The engine-driven type of pump is at the lower left in the above photo;...these come in kits with various sizes of spark plug hole adapters. Only the 14 mm spark plug adapter is shown in the photo. NOTICE above it are two coiled-up Sash Rod springs, available from any hardware store. Those two springs, when you need to use them, are wrapped around the engine cylinder and spark plug metal body, so that the removed spark plug, with its electrical cap attached! can be held to the cylinder fins, to avoid injuring the ignition system during the one-cylinder operation of the Airhead engine. If the spark plug was just laid on the engine, it could fall off, and produce an open circuit, causing a lot of $ damage to the coil(s), that might not show-up immediately. On the 1981+ models you can additionally damage the Hall device in the ignition canister, and even the ignition module under the fuel tank. Damage may not show up right away!
This next photo is another type of bead-breaker....very practical for the home user, and can easily be modified to work well with motorcycle-size wheels by removing the small vertical tab; and, perhaps extending its tail a bit, and using it with two pieces of 2 x 4 allows it to be used with single or dual disc brake wheels, without putting pressure onto the discs. This type of bead-breaker, shown here in its automobile usage style, not yet modified;....is very practical for home use, and not very expensive, and often available from such as JC Whitney; or other stores. There are motorcycle specific versions of these type of tools.
***There is a
bead-breaker combined with tire irons, a clever, if complicated
looking unit, that is called the TireIron BeadBrakR, sold by
I have not tried this unit myself, but have heard favorable reports from those that have purchased and used this item. It completely folds-up and is a small package, totally carry-able on your bike.
Frankly, I do almost all of my tire changes, and there have been hundreds (really!) with three old-fashioned tire spoons.
small compressor, basically a small Slime brand's small compressor.
plastic cased version of the one in the Quite small, fits easily with my
first photo at the top of this page. tire tools, Airhead RT fairing pocket.
This one, in its blue package (the carton Fits tool trays, leaving some room.
it came in is in the photo), comes with a $9.99, Walmart, June 2015. I installed
standard American cigarette lighter plug, a DIN plug, in place of the cigarette
which I changed to alligator clips. It was lighter plug, so it plugs into any BMW
$9.99 at Wal-Mart. accessory socket.
I do NOT recommend CO2 cartridges for repairs. Best is a cylinder pump or an electric pump as shown in the above photos. It can take way too many of the small CO2 cartridges to fill a tire adequately, typically even a handful will only fill the tire partially. Even the larger CO2 cartridges are not adequate many times. Also, if you have to refill the tire if the repair worked only partially in such as seating the bead, you'll likely have no more cartridges. More on cartridges a few paragraphs below!
For TUBELESS TIRES (no tubes inside) repairs when on the road,
you should carry on the bike some sort of tire plugging devices and tools for
them. One common brand is Stop&Go, either the standard model 1075 gun type, or the
compact hand unit model 1000. NOTE that the Stop & Go tire plugs are
also useable for steel belted tires, but
with steel belted tires the injury hole MUST be reamed
really well, with the tool included, before installing
the plug. Failure to do that will likely result in the plug being sheared
and permitting a leak very soon. In general, I
recommend the StopnGo smaller
plugger kit, and ALSO recommend you carry BOTH their plugs PLUS some sticky-strings ...and
glue/cement. Even in quite egregious instances, having a plugger kit, sticky
strings, and extra cement, can be very worthwhile.
There is something hardly ever said, that is favorable for some tires (and, any others similarly
constructed: A tire that does NOT use steel strands in the tread is much more likely to have
a LASTING repair, from use of sticky strings or internal patch. This is particularly so if you
are using such as the Stop'nGo mushroom type of plugs, which require a lot of reaming on
steel belted and steel ply tires in order for them to hold-up. The Avon Roadriders do NOT have
steel plies, and there are many others. Conversely, that makes them POSSIBLY more
conducive to punctures. Strictly speculation!
I personally have had a VERY bad and large tire puncture, not a round hole either, and had to use BOTH sticky strings AND mushroom plugs. Here is a photo and some text about what went into that tire:
When this nasty bit of metal went into the tire, it did not go straight in, but went in on an angle before it straightened out. Thus, the somewhat rectangular and truly nasty hole in the tire it made. Was the devil to get the tire to hold enough air so we could get home. We were maybe 70 miles away, and in the mountains. Towing service asked for $800. NO WAY! I managed to fix the tire enough with sticky tire repair inserts and two mushroom inserts. I carry a tiny electric pump which did fine....and it had to be used to inflate the tire 3 times from flat, and topped off once, and this is not a small motorcycle tire, but a car tire on my sidecar rig rear wheel. Of course I replaced the tire when home.
NOTE that plugs, installed from the outside, are a temporary repair for tubeless tires. You are not supposed to travel far and fast using an externally plugged tubeless tire. Many have done it, but I do not think it advisable and I DO NOT recommend it. Many who have bikes with tubeless tires will carry a tube, for emergency repairs, not trusting external plugs. Many have temporarily repaired tubeless tires with a 'string' or other type of external
plug. Many have gotten away with this
for the life of the tire. My suggestion is that you do NOT do this, but
have your road-side temporary plug repair properly fixed at the next available
dealership.....or, do it at home. So, what I am saying is that tubeless tires should
eventually be properly repaired with an inside patch-plug....or replaced.
Please also keep in mind that if you install a tube in a tubeless tire, you
should reduce the tire speed rating by one step, as the combination causes more
heat to be developed.
WHY I do not recommend CO2 cartridges; & some hints when NOT using cartridges:
I do not use CO2 cartridges. Besides their cost, and bulk,
they will not really do the job much of the time. I prefer the tiny electric compressors
shown above, even
though they have lower instantaneous air available. CO2
cartridges ARE "somewhat" adequate to inflate a TUBED tire after a flat repair or a new tube is installed on the road someplace. It takes WAY too many of of them to actually inflate to the proper pressure....a nasty little drawback, hardly ever mentioned. They are adequate for tubeless tires, BUT ONLY IF THE TUBELESS TIRE IS INTACT AND SEALED TO THE RIM, ALL AROUND, OR CAN BE MADE TO BE SO. They STILL will NOT inflate the tire more than enough to travel at low speeds to a place you can do a proper inflation. If the tire is not properly inflated, it WILL get hot, perhaps TOO HOT. Steel-belted tires will have more flexure at the plug repair, and the steel sharp points will possibly shear it off.
It is NOT unusual for a tire to move to inside the rim when it goes flat. This can occur even with so-called Safety Rims, which have bumps or other changes to help prevent the tire from moving into the center well. When that happens to a tubeless tire, not containing a tube, you MUST find a way to bring the tire sidewall fully in contact with the inside of the rim, in order to inflate the tire. One has a lot of leeway on this in a SHOP situation, because in a shop you have the ability to remove the valve CORE, and use a tire chuck, or modified tire chuck, on your compressor with the tire chuck center removed, and you have strap tools. That type of modified tire chuck, and a tank of high pressure air driving it, gives a LARGE flow of air, just what is needed in marginal situations for trying to seat the tire sidewall to the rim. That is NOT available in the field. CO2 cartridges do NOT have proper inrush.
For those with tubeless tires, NOT running tubes, I recommend your favorite plugs, patches or string or whatever style of repair kit you wish to use (with reasonably fresh rubber cement!). I DO recommend you carry BOTH sticky-strings and some sort of mushroom plugs, and have a piece of rope or long strap that goes around the outside circumference of the tire, which you can use with one of your tool-kit items, like a tourniquet, in case your tire no longer is sealed to the rim. I also suggest tire lubricant (the REAL stuff).
Tire plugs of the Stop-'n''go type are useful, but if you have steel belted tires, be SURE to ream the tires quite well, and be prepared to re-plug and use sticky strings too, if needed, and, of course, re-inflate, if the plug fails.
Hints, methods, advice, ideas to consider, ETC:
If your fuel tank is approximately half full (or more), I "suggest" you REMOVE the fuel tank before repairs, IF...IF...you have to lean the bike over on the ground.
One very popular method of repairing the rear tire on ALL twin-shock airheads (some do it for Mono and Paralever bikes too) is put the bike on the center-stand and then to SECURELY! tie the center stand to the front exhaust crossover pipe. Remove the front wheel, tilt the bike forward onto the fork lowers, onto something like your gloves, etc., to protect the fork bottoms. Be sure to bungee any disc brake calipers so their hoses DO NOT have sharp bends, especially at the fittings ends. NEVER hang disc brake calipers by the hoses!!!! This crossover-pipe method is what I personally do. I HAVE, in the boonies, simply removed the fuel tank, and laid the bike over on whatever the surface is.
Below is another method of strapping the center-stand ...here it is to the front forks. Note that the owner is not using any strapping of the front exhaust crossover pipe to the center-stand. Photos courtesy of Dann Rudd (which I cropped). You really want to be sure that the strapping can NOT come off suddenly. YOU MUST, if doing it this way, do it such that the bike can NOT fold-up the center-stand during the lashing operation!
NOTE that if you modify your bike so there ISN'T any front crossover exhaust pipe, you will have to figure out a way to tilt the bike forward, somehow securing the center-stand, to remove the rear wheel.
NOTE: in the photos below, Dann has the strap around the very bottom below the axle fitment projections of the fork lowers. Be very careful that the strap can NOT come off the lowers. The bike is being tilted forward so that easy removal of the rear wheel can be made.
In general, you will have only REAR tire flats:
In a field situation, I remove the front wheel, re-insert the axle, and tie the axle VERY SECURELY to the exhaust front crossover. I tilt the front of the bike down onto the ground. On the ground I have placed one of my gloves to be under the left fork lower, and one of my gloves to be under the right fork lower.
What follows in
this article is a lot of information on how
to deal with a tube puncture, and how to patch the inner-tube; how to R/R tires
and tubes, ETC. If you do it my way, you will not likely have patch
failures, and you will not likely have tire mounting problems. There
is a LOT of information here. SOME will definitely apply to YOUR bike.
The best on-road fix is to discard the old tube and install a new one with tire talc put on by your hands. It is also MUCH faster than removing, patching, and reinstalling the original tube. Purchase another brand-new tube for your on-bike repair kit items soon. Don't forget to remove the offending nail, screw, etc., from the tire...many have forgotten to do so!! Unless your front and rear tires are the same size, or close to the same size, it is really best to have both sizes of tubes. Many do not, and carry just a rear, which can be put into a front in many instances (such as 18 rear into 19 front, but not recommended for 18 rear, 21 front, obviously).
The next best choice is to repair the tube and continue on.
NOTE: Some do not carry tire repair items, or have limited items, or install some sort of sealant product into their tires or tubes. YOU have to decide what YOU are going to do.
NO TUBE that has extremely long splits, tears, etc., should be
patched, and usually the patch is not successful if huge, on a
motorcycle-sized (or bicycle-sized) tube.
Butyl AND natural rubber tubes, with punctures or small tears/slits, etc., are certainly patchable, contrary to some beliefs.
Most people fail to first roughen the tube and clean it properly. Most also slather on WAY too much tube glue (DO check now and then that YOUR glue is in good condition!). They also fail to dry the applications of glue the correct amount of time. They additionally fail to allow a long-enough final cure. All these things can lead to patching failures.
In April 2013, I changed this entire article extensively, so that it INCLUDES lots of additional hints, etc....on what you might do for removing and installing or just repairing a new tire (or tube) IN YOUR SHOP/GARAGE and when on-the-road. Because of these changes, use what portions of what follows, for your specific situation. Because of many variables, the rest of this article is not necessarily in any specific order of events.
There is a lot of misunderstanding about tubes, tubeless tires, tube-type tires, types of tubes, etc. This is slightly edited from a posting I did to the Airheads LIST, on 04/05/2015. A lot of information follows this section.
""The insides of tires vary between models and manufacturer's. This particular variance happens on both tube rated tires and tubeless rated tires (which can be used with tubes). The inside of the tire may...or may not... have MANY RIDGES, that you can see, and feel. These ridges are on an angle (SUPER NERDS concern themselves with those angles and tire rotation direction, if not marked, most of the time the tire IS marked for one of several reasons) and provide places for the TUBES to press-against, and thereby the tubes deform a bit to the ridges during inflation, and so are more or less captured in a more or less fixed position. The tubes are then less likely to rotate inside the tire upon a flat being experienced. A bit of allowance, in case movement does happen (more likely on NON-ridged insides of tires) is had by following BMW and other advice, and NOT screwing the installation nut down to the rim...but, discarding it...or moving it up to the valve cap. THAT is proper, and allows the tube to move a bit, before forces would tear-out the entire valve stem, making not only for an UNrepairable tube, but allowing, typically, a very fast air release.
NOTE that the 'plastic tubes' are much more conducive to this type of damage.
Plastic versus rubber (or natural rubber) tubes: The prime difference in materials is the percentage of the two types in any given tube. There are NO 100% natural rubber tubes; nor, AFAIK, no 100% plastic tubes. I could be wrong.
In order for the tubes to properly equalize to the tire inside, and that includes the movement during normal tire rotation as you ride, and to ease installation, tire talc is generously applied to the inside of the tire, and onto the tube surface too, by one's hands...rubbing it into the materials....during tube installation...including when installing a new tire.
If you remove a tube for a patching, and reinstall the tube, it may or may not align itself with those tire ridges again. Under the best of circumstances, the alignment is not perfect. If the tube sides are reversed, they will NOT align, EVER. The bottom line here is that the tube is stretched and thinned in tiny areas, where these ridges made tube changes. Thus, the tube is weaker at those areas. The tire and tube makers always say to replace the tube, rather than repair it....or, they say to always replace the tube with every tire change.
Obviously, the implication, and sometimes this is stated, is that a reused tube, patched OR NOT, is less strong. Thus, a patched tube should be regarded as a temporary on-road emergency fix. I completely agree.
We all know few pay any attention to these things. Some have gotten bitten.
Guess what type of tube material is less conducive to blowouts or serious air releases upon a puncture (or, break at a ridge line mark)...?
The main section begins here:
start working with an existing tire on the wheel, deflate it by REMOVING the
Schrader valve core. "Break" the
tire bead on BOTH SIDES of the wheel. PUSH the valve stem (on tubes) to the inside. REMOVE the
tube. Remove the tire. When you replace a tire, inflate the tube a small amount, just to shape it
a bit, and install into the tire. Put the wheel rim on an angle, and insert the
tube's valve into the rim hole. Feeding the
tube stem into the rim hole can be fun. There is a tool for that that makes it easier. Later in this article I will have
some specific advice on that. Once the stem is inserted
through the rim, put on the nut a few threads. START spooning the tire at a point totally away from
the valve...the opposite side of the rim. Repeat on other side.
There is a lot of confusion about tubes and installing them. Here are some details:
1. They should be installed using a fair amount of plain unscented talcum powder (sold cheaply for tire/tube repairs), pour some on your hands, and rub lightly all over the tube...and repeat for the inside of the tire. You need NOT apply any on the tire BEAD area.
2. Tubes come with plain stems vulcanized to the tube; and may or may not have a concave washer, and one or two nuts, and a cap. The cap may be a metal type with a rubber internal air seal, or a plastic type, that also seals air. The purpose of a concave washer, if the tube comes with one, is that the construction of the tube valve area is such that the concave washer goes on the valve on the inside of the rim. If there is no concave washer, you do not need it with that particular brand/model of tube. Unless it is missing! For TUBELESS TIRES being used on TUBE TYPE RIMS, the rim hole is 8 mm. If you do not wish to enlarge the rim hole for a standard pull-in type of stem, then there is a special valve stem that is available, even from BMW, that seals at the inside of the rim by means of an O-ring built into a recess of the stem unit. The stem area of the rim, inside, must be machined flat for this to work well.
3. If there is a single nut, that is used to help you with installing the tube into the rim hole. That nut is put on the OUTSIDE of the rim, TEMPORARILY. When the tube and tire are fully mounted, the stem must be at 90° to the rim. Once it is, either toss the nut, or, screw it up to the CAP. The nut is NOT to be tightened to the rim.
the tube stem must be free to move about a bit in the rim; this helps if the tube and rim rotate a slight bit to each other, it avoids the valve assembly ripping out of the tube. The stem also acts as an indicator, and if it is not, in the future, at 90°, you know the tube has rotated.
4. If there are two nuts, the primary purpose is to allow use of the tube in a TUBELESS RIM. That is because the valve stem hole in a tube type rim is 8 mm, and for a tubeless rim it is 11 mm. The inside nut is usually a hex type, and the outside is usually a knurled round type. If there is a concave washer AND this second nut, you could use both. In this situation, however, I carefully inspect how the tube was constructed, and I may well not use the inner nut. In any case, do not screw the inner nut, if used, tightly. NOTE that the concave washer may be better to use than an inside nut. INSPECT your tube!
NOTE: If installing a tube, be very cautious about trying to seal the valve stem to the
5. Most everything else:
Many install the tire on one side, then install the tube, then install the second bead. Be very
careful, no matter how you do yours, that you do NOT pinch the tube with your tools!!! It is even
possible to put a hole in the tube in the VALVE STEM area, if the tire bead is trapped and moved
about at that point. Take your time to watch what you are doing.
a. Any puncture or tear needs to be cleaned up, sanded/abraded with a inner-tube metal abrader, and
best to do it VERY thoroughly; don't use sandpaper, unless you have a way of solvent cleaning the
area afterwards. Next clean the area with alcohol or other solvent; gasoline is NOT good here, it
MAY have ingredients that MIGHT prevent solid patch adhesion. Gasoline is better than nothing.
b. Using one of the repair kit patches, peel off the protective layer, KEEP FINGERS OFF THE ACTIVE
STICKY SIDE, & using a CLEANED fingertip, spread the smallest amount, thinnest layer, of the
cement goo on the tube, and the patch's active adhesive side. Yes, BOTH of them. BE SURE the
patch is covered to its own edge. BE SURE the tube is properly prepared and you kept your dirty
fingers off of the repair area and patch active surface.
c. Allow each application of the tube's goo, in tiny amounts remember!... to dry. How long depends on
humidity and temperature. I suggest several minutes.
d. Repeat the fingertip application of glue THREE TIMES. Use the TINIEST amount of goo!!! On the
last application, before it is totally dry, press/clamp the tube and patch together, and leave clamped
for a day or so if at home. If doing this on the road, try to clamp with some sort of flat wood or ?, as
flat as you can; and try to have the patch lay quite flat, particularly at its edges! Allow as much time
as your patience allows.
e. When installing the tube, use your hands with TIRE talc all over the tube, and inside the tire. I like to
wait a bit after inflating, perhaps 15 minutes or more, before riding on a patch job. My personal
method of on-road repairs, AND in my garage, is to R/R tubes with one side of the tire still inside
If your tire is marked on either sidewall that it is to be installed in one
direction, pay attention to that.
On BMW twin-disc wheels, the carrier NUTS are normally on the LEFT; which, thusly, identifies the
wheel direction of installation. Many wheels and some discs, are marked for direction. Whatever
your wheel is, keep it that way, or you will need to re-break-in your disc brake pads.
g. Install one sidewall of the tire onto the WELL-CLEANED inside rim surface first, using tire spoons
and REAL tire lubricant. Cleaning the rim bead surface is important, do the best you can if on the
road. I've carried sandpaper for this purpose. At the least, use gasoline and a rag.
(careful! flammable!!). It makes for easier bead seating.
h. Note: Sidecarists sometimes use rear tires at the front, and front tires at the rear. Sidecarists may
mount those tires with the arrows in opposite direction from the tire markings.
Do NOT generally do this on a 2-wheel bike. BUT, some tires now come with molded sidewall information
that tell you which direction the tire should be, for front or rear use!
Sidecarists and some 2-wheel riders also do strange things, such as using
rubber pieces under the rim where the valve stem sticks through, and rubber on the outside, then
have the stem nut and cup washer against that. The idea is that the tire, whether a tubeless type or
not, will hold some air, for awhile at least, if the tire/tube is punctured. Normally, the proper
installation is no rubber things, and the nut that comes with tubes is threaded UP to the TOP of the
valve stem, meeting the stem air cap. The idea being that if a flat occurs, the tube (you DID install it
with tire TALC all over it surface, and tire insides too?) can move a slight amount, with tire
movement on the rim... avoiding having the tube stem rip out, making for a very sudden flat. BMW
even had a bulletin about that....more on this below.
i. Use TIRE talc on your hands to get the tube surface & inside tire surface slippery, before installing
a tube. Install the nut onto the tube valve stem, a few turns. If the tube came with TWO nuts,
and/or any cup washer you can use the cup or not and can leave the inner nut, or not, depending on
YOUR rim & tube. If you discard one nut, keep any cup washer the tube came with, onto the tube,
only IF appropriate to YOUR TUBE AND RIM. Put it INSIDE the tire, if it fits the stem and rim
properly. YOU WILL want a nut for the outside, for the specific purpose of assisting you with
keeping the valve into the rim hole.
HINTS: Feeding the tube stem into the rim hole after the tube is otherwise fully inserted into the tire
may be difficult; especially if the sidewall is quite stiff. The sidewall may need considerable finger
pressure, & some may use a small block of wood to keep the sidewall a bit more open. If you go
too far with that idea, the other side of the tire will move & block the valve access. Some have
used forceps gripped onto the stem threads to help guide the valve into the rim hole. I recommend
you do NOT using any tool that can injure the threads. There is a thin braided steel flex cable tool
available, it is specifically for doing this job. It screws INTO the valve stem. Tusk Valve Stem
Puller part number 1188500001. Get one of these; try your autoparts store, if necessary an
Below is the type for tubeless rims for pulling the valve stem into place. If you modify it, it will
work on tube type rims. The Knurled end of this tool, see photo note, as purchased will NOT fit
through the smaller diameter TUBE-type rim holes; it WILL, if you carefully thin the outside diameter,
by grinding the knurled cap end a bit thinner. Grind the O.D. just enough so it goes through
the rim hole without forcing it, and NOT MORE, as then the walls will be too thin.
Haltec TL-645-24, or Grainger 33510, or similar on Ebay.
Get ONLY the flexible cable type as shown here. One of the dual-barrel
ends of this tool is to R/R the valve core, and the other is to depress the center pin of the valve
core on an already inflated tire, and there is a small side hole; this allows the air to come out
slowly, avoiding you unscrewing the valve core and have it flying into 'never-find-land'.
Once the tube valve stem is in the hole, using one of these two tools, then put the nut on the stem,
only a few threads!
You also want to line up the painted dot or other
painted marking, if you have such on the tire, with
the valve, when installing the tire onto the rim, before spooning the second sidewall onto the
rim....this is a good time for more tire lube...note that tire lube is used on the bead seating area of
rim/tire...and, on the EDGE of the tire bead area.
Although this is best avoided; if you have to, move
the OUTSIDE nut down fully to the rim, & move
the tire slightly one way or the other (NEITHER bead has snapped to the rim yet, because you have
NOT inflated the tube/tire) so the stem is centered and at 90°, in the rim hole. DO NOT spoon over
the final bead NOR inflate until this is so. It is best to avoid doing tire movement on the rim. Do
try to avoid this....by lining up the tube stem and tire to the stem (if it has a paint mark), all at the
same time, BEFORE spooning the final bead onto the rim; is that the ease. You really do not want
to have to try moving the tire in relationship to tube/wheel....as such movement depends on the
inside surface of the tire, and if the tire talc you applied is going to ease the friction enough. You
also would need to have the outside nut hold the valve pretty tightly to the rim. That's not the
greatest idea either. You don't want to put excessive force on the tube!
Assuming you have the tire and rim and tube valve in proper alignment, have the nut upwards a
number of turns. It is best NOT to have the nut down to the rim and tightened just before inflation.
The purpose of the outside nut is ONLY to keep the valve from going back inside the rim during your
work. This outside nut that is used as a tool can be tossed after installation, or, moved up to the
stem cap. I recommend you move it up to the stem cap, as sometimes new tubes do not come with
a nut and I like to have one, in case I do not have the fishing tool, and, it makes things easier even
with the tool. DO NOT leave this outer nut tightened to the rim! Even BMW had a bulletin on
The stem should be free to move about in the rim hole, stick straight out at 90°, and not on
an angle, when you have the tire/tube/wheel properly assembled and inflated. You cannot!!
determine if there is any side forces on the tube, unless you have the nut loose, during and
after inflation. When done, THEN you can put the nut against the cap. DO NOT fail to use
a cap that SEALS well.
Obviously if you have a tubeless
tire, used as tubeless, you have NO inner-tube, and you
have NO inner-tube type of valve stem to worry about.
j. On a rare occasion a tire will not balance properly without a large amount of tire weights added. It
is OK to have the tire painted mark at 45 or even 90 degrees to the stem, if doing so reduces the
amount of weight needed. VERY FEW motorcyclists do this, as they hate bead breaking after
mounting a tire, and you must be careful with a tube.
k. Many modern motorcycle tires have VERY stiff sidewalls and are NOT
very easy to put onto a rim.
In addition, you MIGHT have a problem getting the tire bead to seat all around on both sides of the
wheel. Copious quantities of tire lubricant WILL help. Often the tire beads snap into place over a
few minutes. A big help is to have the tire, wheel, tube, etc., all in the hot sun for
quite some time, before and during ANY tire work.
Use of too high pressures are dangerous. I will give you some hints/advice that will work for
you....but some of these are only for the shop/garage situation.
Occasionally there are problems
and even with repeated inflation, deflation, inflation, a clean rim and
lubricated bead, the tire may not seat all-around. This usually happens on just one side of the wheel
and on a smallish part of the circumference of that particular bead. While it is true that....in VERY
rare instances, a tire is faultily made...or a rim unequal on each side (usually due to straightening of
the rim at some time), those are VERY rare instances.
l. To avoid problems, I recommend that you follow ALL my suggestions FIRST, ahead of
time...as best you can with your equipment, ESPECIALLY when doing a tire where your
compressor and tank are available, and, frankly, here I mostly mean your own garage/shop,
although some of my suggestions can be done anyplace:
CLEAN the rim inside bead area wall, so it is clean & very SMOOTH...this allows the tire bead to
slide up the bead area easier during inflation. Use liquid solvents first, finishing with fine sandpaper,
then clean off any sand from the sandpaper, then WASH with soap & water to remove any remnants
of prior tire lubricants, etc. I cannot over-emphasize the need for a clean & smooth rim where the
tire bead seats. This is VERY helpful for both tube & tubeless tires in both spooning-on, AND in
later having the tire set fully concentrically to the rim. Doing it properly will reduce your swearing
& labor CONSIDERABLY. A rather minor-appearing irregularity on the rim bead surface will be
a point of substantial friction, which you do NOT want, once the tire bead is in contact with it.
Do NOT leave the Schrader valve core inside the valve stem when trying to seat the beads from
your compressor's tank. That valve, together with perhaps your air source being of too low a
pressure, or too small a tank or no tank, too restrictive a hose (or chuck!!)....may not allow a
fast-enough inflation. FAST inflation is one of the super-secrets....otherwise, the lubricated bead
STARTS to move & seal, & then hangs-up. Many have very considerably overinflated a tire (to
quite dangerous pressures) & still could not get the bead to seat.
m. For tires withOUT tubes, there is another possible problem, & that is to get the tire to even start to
seal to the rim, let alone fully seat/seal. This is ESPECIALLY a problem if you have a very output
compressor (12 volt, on the road??) or limited large CO2 bottles. The answer is almost always a
big belt or rope used as a tourniquet, around the entire circumference of the tire. Use a large tool of
some sort, even a piece of wood, to tighten the tourniquet.
n. So, heed my hints!
I cannot overemphasize the need to do what is in this section!
HAVE THE TIRE & WHEEL HOT! Remove the valve core & use a compressor hose, &
associated parts including fittings & airchuck, that flow fast in volume. DO USE a modified
airchuck that will fill the tire FAST (with well-lubricated tire bead too, of course). A several
gallon size (OR MORE) TANK at the compressor, high pressure (at least 80 psi, but 125+ is
nicer) is very helpful to supply the huge amount of air FLOW really needed. Check that the
air HOSE is of the 3/8" MARKED type, NOT smaller; or flow will be slow (low flow volume is
is BAD). Do NOT purchase an air hose that has a small hole inside at either end fitting,
17/64" or 9/32" is needed. The hose length is NOT very critical, but the shorter the hose the
better. The entire air supply system needs substantial INside diameter parts.
I have found that SOME quick-release hose fittings are quite restrictive.
It is best to avoid
them. Modifying quick-release fittings is iffy...best to avoid doing that.
OBTAIN AND MODIFY AN AIRCHUCK specifically for filling tires/tubes: REMOVE the center
pin. LEAVE the rubber washer in the chuck (after you modify the chuck). DRILL the part of
the airchuck that attaches to the air hose, for a larger size hole...all the ones I have seen are
too small in diameter. 15/64" or 1/4" will be OK.
USE REAL TIRE LUBRICANT, properly thinned. USE A 2" wide cheap paintbrush
to apply it
quickly, and so both rim & tire bead are well-coated. If it starts to dry, re-apply or use a
water spray from a cheap plastic bottle sprayer.
o. I can't tell you a specific maximum pressure to try to seat tire beads; frankly I do not know what is
truly safe for your particular wheel...let alone any particular tire. Motorcycle tire manufacturer's use
to say not to exceed the maximum sidewall printed pressure by more than 50%. Some said 150%
...which they meant as 50% over the maximum sidewall printed figure, but that could be
miss-interpreted as sidewall printed maximum pressure PLUS 150%. I CAN say that THAT would
be SUPER DANGEROUS. Recently, perhaps lawyers got involved with the litigious American's, as
many tire makers are saying not to use higher than 40 psi when inflating. Some of these same
manufacturer's have deleted their prior higher recommended pressures for RIDING too! This all may
fly in the face of ~ 42 psi being a maximum on many sidewalls. I like the old recommendations
myself; & to restate them: DO NOT use over 1.5 times the printed sidewall maximum. Speaking as
my lawyer might advise me (besides not to say ANYthing), I am not advising you DO use 1.5 times.
My information, which you are reading, is of how I PERSONALLY DO MY OWN REPAIRS.
I would NOT want to inflate a tire so high that a rim exploded, let alone the
tire be injured. There is
always the chance that a rim has been weakened, making things even worse! I never ever go over
I use a compressor that fills its tank to 125 psi, & I use all my previously noted hints about hose size,
air-chuck modifications, no Schrader valve core, etc. I usually use a gauge in the hose fitments, to
tell me the PSI that the tire is being filled to.
Please keep in mind that while a pressure change from, say, 50 to 60 psi seems hardly much, the
truth is that the pressure is POUNDS PER SQUARE INCH...and there is a lot of inside VOLUME
AREA for those pounds. Thus, the pressure on the wheel can be MANY THOUSANDS OF
POUNDS; and an increase of just 5 psi is a LOT, considered as on the total surface area.
In my own shop/garage, I have a pressure regulator on the output of the compressor tank. I set it
for 85 psi when doing tire work. That has been high enough to get enough air flowing quickly
enough. You might want to eliminate any pressure regulator, and thereby obtain a faster FLOW
rate....on some regulator types, it is of no help to set them higher. Do NOT take the tire to any sort
of too high pressure, however. If you are the very anal type, you might want to fashion some sort of
pressure gauge that is "T'd" into where the modified airchuck is is fed from the hose. I have NOT
had to do this. I inflate the tire to a good guesstimate, check the inflation pressure with my stick or
bourdon gauge, then inflate again, etc., until I get my maximum, IF I NEED THAT MUCH.
I WANT TO EMPHASIZE THAT THE BIG SECRETS ARE THE RIM PREPARATION AND THE
SPEED OF INFLATION (the FLOW RATE) AND having a HOT TIRE & WHEEL. Once the
WELL-lubricated beads snap into place on both sides of the tire, & not exceeding a safe pressure, I
check the RIDGE that is molded on the tire near the bead, to be EQUAL all around, on BOTH sides
of the tire, concentrically, all-around. IF NOT, I deflate, break the bead, lubricate, repeat the
process. If you do this procedure the way I have outlined, you will almost always have 100%
good results THE FIRST TIME, AND NOT HAVE TO DEFLATE & TRY AGAIN.
p. As noted earlier, I use REAL tire lubricant with a paintbrush. Tire lubricant comes concentrated &
looks like very thick jelly. I thin it with water per the can. If it dries out, add water from a
hand-sprayer, or more tire lubricant. DO NOT use lubricants that contain oils. I am well-aware
that some of you will use saddle-soap, dish detergent, soap, etc. You have MY recommendations.
A tire from any one given manufacturer is intended to be used with some other tire from the same manufacturer.
In a fairly large majority of instances, tires can be mixed by model and manufacturer with no or few problems.
In some instances they do not work well with each other.
Every tire has its own type of vibrations set up in the tire & transmitted to the suspension, frame & you. Even if the tires are perfect, & balance of wheel and tire is perfect, these vibrations still occur, & if the front & rear tire were not designed to work with each other, strange effects can come about. Vibrations come from from the tread design and how it pressures air as it rolls down the road, plus rhythmic things that come from tire tread squirming, ETC!
ONE of those fun things is when such effects in one tire creates something almost like a musical beat note with the other tire's noises....OR, what is created is a rhythmic vibration and/or noise, something like a regular interval thrumming that rises & falls in amplitude as speed decreases & increases, from any one speed.
In some instances, even proper mating tires can do this, depending on wear patterns, & a LOT of other things. Some of these things, and/or causes, are not well-known or thought about. On Airheads, insufficiently tight motor mounts, for instance. Shock absorbers can have a dead place that is exceptionally narrow in stroke amount, & can cause vibration. If you change the loading on the bike, thrumming may mysteriously appear or disappear. Balancing tires & wheels might only help somewhat, if at all....since often balancing is NOT the basic problem. Just about anything that changes the characteristics of the bike in some way, will allow new or different vibration modes.
Other items that are often at fault are twisted forks, forks with stiction, looseness almost anyplace, & sometimes 'things' added to the bike that change vibration modes from the stock situation. A flattened center-section of the REAR tire from normal wear can cause thrumming, noises, and be VERY dangerous at speed, as it promotes high speed INstability, even of the type known as a Tank-Slapper.
In some instances vibration and thrumming begin after the front tire is worn, this happened now & then with the Metzeler Laser, which is very compatible, due to tread design, with almost any rear tire. The Metzeler Laser is hardly the only tire to have these problems now and then.
Braking/sliding that causes a worn place over one area of the tread, and not another, is a VERY prime cause. This often comes about from either very strong braking & sliding on an abrasive surface, that flattens, ever so slightly, part of the tire. The type of thrumming this causes can be exceptionally pronounced.
My point is that before blaming tires & balancing, DO check your nuts & bolts, & feel the front end for the steering head tightness or looseness & rear suspension. Check the rear wheel fasteners; particularly on the single-sided models....they do have a torque setting, & those threads are never to be lubricated, & that includes not ever using antiseize compound on them. If you cannot find the problem, remove the rear shock absorber(s), remove the springs from them, & test them over VERY SHORT movement conditions, in the SAME vertical/horizontal alignment as if on the bike.
There ARE mechanical things with the driveline that can cause rhythmic vibrations. Usually an experienced wrench can determine, from speed and modest riding tests, where the vibrations are coming from. One of the high frequency vibrations that is difficult to figure out is from a driveshaft of the type with two U-joints, that was installed with out-of-phase U-joints. See my http://bmwmotorcycletech.info/phasing.htm article.
SOME vibration/thrumming can be serious, such as a loosening nut at the nose of the rear drive; an internally failing cardan bearing, a transmission failing, etc. Phasing problems are usually more constant, same for internal problems.
(1) Modifying the rear fender, rear sides & rear bottom on
Airheads, can make for MUCH easier
tire/wheel removals. This is easy to do, can be done so no one notices, and can be very helpful. The
rear fender, a composite material, is relatively easy to cut with a hacksaw blade in a single blade
holder, & easy to smooth that cut edge with a common file. Using a piece of chalk (or?), mark the
fender from the side opening, downward/rearward, smoothly, to the bottom of the license plate.
Do on both sides of the fender. Cut and smooth. When done, the fender should end approximately at
the lower edge of the license plate. You can, not necessary, install a rubber mudguard (mudflap), such as
from JC Whitney...or the ones I prefer, the BMW ones (pricey though). Note that fitment years shown
below is not absolute, you may be able to use any of these. Differences include whether or not they
are complete with hardware, or have BMW emblems.
White, now no longer available unless you find a dealership with some: 46-62-1-239-274, fits from 9/78
Black, 46-62-1-236-384, up to 9/78
Black, 46-62-1-230-766, up to 9/78
Black, 46-62-1-230-797, from 9/78
Black, 46-62-1-238-996, from 9/78
Check the dealerships' ETK's for number & fit/model; those numbers may be superseded or obsolete.
If you do the below fender cut smoothly & neatly, it will probably never be noticed by
anyone as not being stock. It makes removal of the rear tire easier on the twin shock machines.
This is a photo of my 1984 R100RT that
had the modification, including a mudflap.
as the front tire is typically on the ground at the same time the rear tire is, making for difficulties when
trying to remove the front wheel for a rear tire flat; that is, for tilting the bike forward as described
earlier. Parking the bike so the front wheel is over a curb, with the bike on the center-stand, is one
idea...DO tie the center-stand to front exhaust pipe. At home, you can jack the bike in some fashion
that works well. I typically use a board under the center-stand for tire work on Reynolds Ride-Off
Stand equipped bikes. See notes much earlier, about half-way down in this article.
Note that with a stock rear tire, changing the front tire to an oversize type, can cause the same problems.
(3) The Chitech folks have a booklet on doing tire changes. Good information, but rather obsolete in
SOME ways now.
(4) Tire Pressures:
The BMW factory recommended tire pressures for your early Airhead....certainly prior to the mid-1980's...is probably
too low. A good beginning pressure is the tire manufacturer's published recommendation, if higher. BUT...many tire
makers KNOW their published pressures are not high enough and they use BMW's too-low pressures. Lawyers?
You will probably find that for modern tires the appropriate pressures are LOW-thirties for the front and higher thirties to even as high as the sidewall limits for the rear. There is an old rule of thumb that says that the tire pressure should increase about 6 to 8% from cold check, to being checked IMMEDIATELY after a ride. The rule says that if the pressure does not increase that much,.. then lower the cold pressure, and vice-versa, of course. That rule works well sometimes, but NOT always.
Tire pressure needed varies with the loading (are you heavy? two-up?), and speed you might travel at.
For the CLASSIC BMW airhead
ride, use the stock sized tires, in the old ribbed
designs....with the original manual-stated (or under the seat
label) pressures. These pressures are NOT correct with modern tires, particularly on pre-1985 bikes. By the nineties, the BMW recommended pressures were OK....but not necessarily really good.
FOR YEARS I have been telling people that the tire pressures printed in your owners booklet, and in various literature, and very particularly so for BMW's made before 1985, after which tire pressure recommendations are a bit more reasonable (but not perfect, in MY opinion), are much too low....for modern tires. Here is a page with charts of recommended tire pressures. I ran across this information in November, 2014. I agree with the page.
The tire pressures shown in your early owners manuals are likely too low for MOST ALL modern tires. This is particularly so for the models before BMW changed the front wheel from 19 inches to 18 inches; as a general rule, all bikes before year 1985 have too low a recommended pressure for modern tires. You can probably just assume that information on pressures were TOO LOW. Using too low a pressure leads to mushy handling, shorter life, and less crisp handling. You can POSSIBLY determine the proper pressure for the tire, weight, speed, etc., of your type of riding, by measuring carefully the pressure before and after a decent ride at cruising speeds. The change is small, on the order of about a pound to 4 pounds (extreme conditions) and hard to read accurately. MY Rule of Thumb of 6-8%% rise is proper after a fairly decent ride length, especially at goodly speed, and if less than 6%, DEcrease pressure, and vice versa. SOMEtimes this rule of thumb does not work, and it appears it does not work too well with very stiff sidewall and some belted tires, which have less increase in pressure. Following the TIRE manufacturer's recommendations USED TO BE more likely to be correct than BMW's early recommendations. Some manufacturer's KNOW that BMW pressures are too low but are UNwilling to take on liability by publishing their own recommendations if different. SOME manufacturer's had the higher recommended tire pressures in their literature, and around year 2000 or so, changed to the BMW recommendations...probably lawyers were involved. MY recommendation is to adjust pressure by FEEL on the road, and to NOT use the pressure rise method.
BMW owner's booklets, and books like Haynes and Clymers, show BMW's recommended tire
pressures for the recommended and standard tires at the time of manufacture. At times, BMW
issued Service Information Bulletins (SI's) on tire recommendations. BMW sent SI's on tires to
dealerships for some years during Airhead production. BMW quit recommending tires for Airheads
a long time ago. It is IMPORTANT to realize that BMW's tire pressures were always a compromise.
It is also IMPORTANT to realize that most of the early types of soft sidewall tires are NO LONGER
MADE. BMW's compromise was between comfort, handling, and tire life. BMW continued this
practice, more or less; up through the ~1985 model year, and to a small extent, to the end of Airhead
production. From ~1985, pressures are more realistic for better handling, although some advice &
experience will help. Typically improvements are still made for handling by some increase in pressure.
Because of these things, IN GENERAL, BMW's tire pressure recommendations in their owners
booklets (duplicated by such as Clymers and Haynes), before 1985/1986, are OFTEN MUCH TOO LOW.
All this is in MY opinion; but substantiated by others. PARTICULARLY with modern tires. I suggest
you be VERY cautious about even trying BMW's old pressures, which were in the high twenties for
front tires, & low thirties for rear tires.....depending on load and speed.
You can do your own testing, starting at low, or high, pressures. I suggest you start with higher
pressures, perhaps 36 front and 40 or 42 rear. That way, you may get a better feel for things.
Consider speeds, loading (2-up? heavy?). I think you will find that FRONT tire pressures of about
33-36 will be correct; REAR of 38-42, for most conditions and situations. The highest of those
pressures would be for high speeds and/or high loads, or very aggressive heavy riders in twisties.
Pressures are always measured with a KNOWN ACCURATE gauge, tires cool
(that is, UNridden, & NOT sitting in hot sunlight).
More information on tire
pressures and a lot more are in http://bmwmotorcycletech.info/section5.htm,
and, for wheels, in http://bmwmotorcycletech.info/wheels.htm
(5) Here is a FUN photo of not just simple
studs, but extreme studding, used
for ice-racing, etc. This particular
photo is of a front wheel. I will
eventually add more information here,
on all sorts of studding, chains, ropes, etc.
for front and rear. Some photos of snow
weather with various tire straps, etc., is
likely in my photo galleries on this site already.
(6) Not many of us ride on the original ribbed front tires any more. They do tend to follow rain
grooves, contrary to what is said in some Clymer's publications. Still, you MAY want to try a
SET, as they DO deliver the classic ride & handling that the bike was designed-for. These
tires generally work best at the originally recommended by BMW tire pressures (label
was under the seat, see your owners manual too), or slightly higher (by 2 psi front, 3 psi rear).
Also note that these tires DO give decent mileage before they wear out. If you have a
modified suspension, the classic ride & handling will be modified. I suggest the Continental RB2/K112.
MANY, if not nearly all, 'modern' tires require considerably higher pressures
THE TIRE PRESSURE LISTED ON A TIRE SIDEWALL IS ...NOT!!!!.....THE
07/26/2008: All prior updates incorporated, and article revised extensively this date
12/28/2008: Edit for clarity. NO substantial changes.
11/01/2010: Expand on #5
02/19/2011: Revise numbering, add section on exactly how to repair inner-tubes
04/11/2011: expand on why I dislike CO2 cartridges
08/29/2011: Add info on bestrestproducts TireIron BeadBrakR, inadvertently left out of this
article several years ago!
03/16/2012: update slightly for clarity
05/03/2012: Add photos for second method of tilting motorcycle forward. Clean up the article
in various places.
10/15/2012: Add QR code, add language button, update Google Ad-Sense code, modify
photo, other minor stuff.
12/15/2012: Add photo of studded front wheel at item (10)
03/11/2013: Minor improvements to the article. Add entire section on how/why flats occur.
04/22/2013: Add more on tire pressures.
04/24/2013: Add more information on difficult-to-mount tires. Revise whole article for better clarity.
04/25/2013: Additional tests proved that some couplers & excessive hose lengths DO detract. Added
the information & did extensive final editing on all parts of this article.
05/26/2013: Add Tusk inner core valve stem tool description and photo, and revise section i.
07/02/2013: Add section on vibration/thrumming
09/26/2014: Clean up article.
11/02/2014: add link, comments, etc., to #4
04/05/2015: Add section on comments made to the airlist this date
05/25/2015: Add more commentary about Stop'nGo plugs, and steel plies in tires, pros and cons.
05/29/2015: Begin incorporating items from catch.htm, tools, etc.
06/02/2015: Revise section on mudflaps
06/19/2015: Add Slime photo and text
11/15/2015: Clean up SOME. Add some links, especially to BestRestProducts.
© Copyright, 2013, R. Fleischer
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