Oils (EXCEPT engine, gearbox and rear drive),
Additives, Greases, Loctite, Sealants, Anti-seize,
Electrical Contact Treatment, Wheel paint ,Waxes,
Tank Coatings, Sealants, ...etc.
See also the paintcodes article!
For BMW motorcycle owners
© Copyright, 2014, R. Fleischer
This article will give the
Airhead motorcycle owner (and some information for Oilhead and K-bike owners)
some insights, some of it in technical detail, about products that I think should be on hand or considered
(and some not!), that will cover most needs.
My shop used, literally, dozens of lubricants,
cleaners, sealants, ETC. YOU
probably only need a FEW of the items mentioned. I
will also provide information from at least one or more BMW bulletins.
There is a Discussion area, at the bottom of this article....it also contains information on the BMW bulletins, etc.
1. One of the FIRST things you should purchase is a squeezable tube of some sort of hand protection.
This stuff is weird, but definitely tends to protect your hands. It is available in small tubs too. Put a bit
on your hands, work it into your fingernails, and all surfaces, BEFORE you start work.
A must item is to get some
waterless hand cleaner, which is available at every autoparts store.
do a LOT of dirty work on engines, etc., you probably will want to invest another 10 or 20 dollars, and
get a dispenser and cartridge. Waterless hand cleaner cleans the messiest greasiest hands ever,
and it is especially super-effective if you use the hand protection stuff above. When you are
done wrenching, you clean up with waterless hand cleaner, wipe it off using an old rag,....followed with
soap and water, ....and you will find that your hands do not look like a typical mechanic's!
Some folks wear surgical or other plastic gloves. I have never gotten used to the feel, but I use them
rather often..... I DO coat my hands with the protective stuff, & still use gloves sometimes for certain
jobs, especially to keep engine oil, gasoline, etc., off my hands to avoid absorbing bad things in them.
Used oils contain BAD things, lthough not nearly as bad as in the old days of leaded fuels. There are
MANY types of plastic gloves available, from boxes of hundreds of "throw them away every 1/4 hour",
to longer lasting NITRILE rubber types (which are quite good). Try Harbor Freight Company for
various types. Many get used to wearing gloves in working on cars & bikes (most professionals do
wear gloves), & it certainly is better for your hands & health; avoiding skin absorption of nasty whatever
stuff. I have both nice nitrile gloves of the thick heavy duty type (50 or 100 per small box) & also very
thin types of gloves of cheap plastic, don't fit very well, but are very useful, come 500 to a small box.
2. Start collecting old rags! (those with a modest amount of $ and who like things neatly stacked, can
purchase bundles of clean towel-like rags relatively cheap from big box stores...you may even want to
cut them into smaller pieces). For the inevitable spills, I cut up old clothing, but I'm a cheapskate.
BTW....you can sharpen scissors by cutting, MANY TIMES, aluminum foil.
Hint: Sooner or later you will have a large spill
of some liquid. You can use old rags, etc. I save &
use them, but I also have powdered concrete & driveway cleaner (available in 5 gallon buckets),
old used solvents, & cat litter. One of the better items for oil spills is Portland Cement...just
keep in mind that it is a fine powder if you are in a windy area. Solvents for cleanup can be
kerosene, Stoddard solvent, etc. Stoddard solvent has many names, INCLUDING MINERAL
3. Waxes, polishes, etc: I am hesitant to recommend any of these, because everyone has their favorites,
often heavily influenced by advertising. There are also some very pricey
super-premium products available. However, my hesitancy or not, here is a list of
some relatively easy-to-find products, that are not pricey, that do a QUITE decent
job, having been thoroughly tested by one or more consumer publications AND
ME. NOTE that I do NOT keep this list up-to-date, & some may no longer be
a. For paint in excellent condition: NuFinish NFP80 paste
b. Very long lasting: ArmorAll Car Wax liquid
c. Weathered paint: 3M #39006 One Step Cleaner Wax, liquid
d. Spray type: Turtle Wax Express Shine
e. Generally good all around: Prestone Bullet Wax
f. Turtle Wax Carnauba Soft T225
g. Very high gloss for excellent paint: Meguiar's cleaner Wax
and Liquid A-1216
h. Pure Carnauba, long lasting, for those who like this type:
Eagle One Carnauba Pure Paste Wax...#2040612
i. This is in RED and emphasized on purpose. For a plastic cleaner/scratch remover, see item
If your paint is terribly oxidized, you may have to start with common "white polishing compound"...or
even, horrors, "rubbing compound". You MUST finish with finer cutting products, then wax.
4. Plastic, such as windscreens....and helmet shields:
Meguire's is the old standby, you will need both their #10 and #17. They are not the very best;
but the Meguire's does do a good job...but is slow, & not nearly as good as my recommendations.
I no longer purchase Meguire's. For very serious deep scratches I use an expensive aircraft window
restoration product kit; I advise against you purchasing such a kit. Below are the top tier items, and
be sure to read d.
a. For light scratches, oxidation removal, etc:
3M Plastic Cleaner #39017.
Max Polishing Systems all metals #1.
Very good: Novus #2 fine scratch remover.
b. For heavy scratches:
Novus #3...follow this with Novus #2, then a polish
Plexus Plastic Cleaner Protectant and Polish.
Kleenmaster Brillianize cleaner and protectant.
Can-Do multi-purpose cleaner/protectant/polish.
Novus Plastic Polish #1.
d. The following polish & mild/moderate scratch remover works quite well, & is my favorite for
general purposes; is not expensive, & I especially like it for for removing fine scratches, and
some slightly deeper ones too, in all types of windshields; face shields, instrument
lenses....just about anything plastic. It seems to have just the right amount & specifications of
various ingredients. The product is Part No. 681 DuraGloss Plastic Polish. That is an 8 ounce plastic
container with flip nozzle top. Car Care Products Company, which is actually Brothers Research
Corp, in Burlington, NC www.duragloss.com. Use this DuraGloss product nearly as-stated on the
container. I use a small turkish towel rag, rub until nearly dry, then polish with a clean dry cloth.
I sometimes follow it by an application of Johnson's Pledge or other semi-protectant....helps make
the bugs removal later on, easier. I don't clean the application rag often, as I can moisten it, and the
left-over stuff works, again.
DO NOT, EVER, use plastic polishes on dirty plastic, always wash the plastic first. ALWAYS use a clean non-abrasive rag. Use a MILD soap, NOT any household detergent. MILD soap is useful....purchase a gallon of it at your autoparts store. It is sold as car washing soap product. A little bit is perfect for plastics....besides being THE soap in your bucket when washing your bike or car!
I have personally tested all the above products, extensively.
When cleaning or otherwise working on your windshield or face
shield, etc., make it a
HABIT to NEVER EVER rotate that cloth in circles, thereby avoiding swirl marks that are
particularly annoying when riding into a setting sun.
Another good idea is to make it a habit of doing the FRONT of the windshield with up and
down strokes, and the rear of the windshield with side to side strokes. That will allow you
to easily see where any problems are during final cleanup, and will reduce glare problems.
I do that with my face shield too. KNOW that some faceshields and sunshields have
different surface treatments on the inside, versus the outside. READ the manual!
5. For the oil in your spout oiler, for use at cable pivots, levers (not bars clutch lever pivot, it has a
replaceable do-not-oil nylon bushing), center stand pivots, ETC. Do NOT oil control cable innards; only
the very earliest /5 bikes with original cables had no linings. YES to lubricating the END fitments, and
You probably should use either a molybdenum containing oil, often just called 'moly' and pronounced
'mah-lee'; or, a plain 20 or 30 weight NON-detergent motor oil...sometimes hard to find, but try your
auto-parts store. Use motor oil if you have to. I prefer to have both a moly & a plain oil on hand, in
separate oilers. The reason for the non-detergent formulation (I am being very nerdy here) is to keep
the dirt & wear products forced out, & not suspended. That is not at all widely known. Use
non-detergent oil (NO moly) for zero to moderate speed bushings, like those your starter motor uses,
other bushings, etc. Some may prefer not to use moly at the levers, where they make nasty black
stains on gloves if used excessively. Moly grease is THE BEST for the BARREL PIVOTS. You can
use silicon oil or grease at the levers, it is usually clear. I DO USE moly at the levers, wiping away the
excess. Common '3-in-One oil' is far too light for almost anything on your Airhead. I do not even like
3-In-One on wee shafts and bearings in the instruments, as it gums eventually. WD40 has NO place
on your airhead for true lubrication purposes....although it is good for removing some types of
labels & hardened bug remains. I suggest you do not use WD40 for lubrication of parts. For
plastics, where a lubricant is SOMETIMES required, often silicon oil or grease is OK. Note that
WD40 is a very POOR penetrating oil. I have information on penetrating oils later in this article.
6. GREASE (I HIGHLY suggest you read this ENTIRE section 6):
You can probably use one brand & type of grease for just about everything on your Airhead or classic K
bike. Anal types should get the, or some, specific greases for each specific place. For such as
steering, wheel, and swing arm bearings, etc., you can use a single grease, and then add moly to it for
for transmission input shaft splines (and rear wheel splines on twin-shock Airheads). While you CAN do
as I just said, add moly, that is NOT what I recommend. For those who want to use just one grease,
& then add moly for splines only, then I recommend Chevron NLG1 (or NLG2, slightly thicker & better
for wheel & other roller or ball bearings) Ultra Duty EP red grease. I use that grease 'as is' at various
places; even on my car/truck at U-joints, etc. I am OK with you adding perhaps 30%+ (NOT critical) of
any common high % moly grease, for those applications where one would want moly added (NOT for
tapered or other roller or ball bearings). However, my thinking has changed with the availability of
greases like Guard Dog GD525, and I am no longer recommending mixing....but it still works OK.
Most greases that have a lithium base will mix fine if you want to do mixing & your own testing.
If you have any left-over Staburags NBU30PTM or Optimol paste PL (two greases BMW use to
recommend for splines at various times), it is probably OK to use either as a 30-50% added portion.
Staburags NBU30PTM can be used all by itself for the transmission input splines but I recommend
against that usage. Staburags is NOT a very good grease for the splines. GD 525 or Honda 60 is
Note, that in general, moly type greases are not to be used in bearings. Do not use it in roller bearings,
nor ball bearings.
I do not believe there is any even near-perfect grease for BMW splines applications.
3000 may be "OK" at the input shaft, but it does not contain moly. Mixing roughly 70% of that grease
with roughly 30% of a good moly grease was, some time ago, OK for BMW splines; BUT, at present,
GD 525 is rather a lot better....there are indications that Honda 60 is about the same in some instances.
I am no longer strongly recommending mixing of any grease with a moly greases, because of possible
INcompatibility of SOME of the base carriers, the moly & carrier could separate in use, & the splines will
loose the lubricant by it being pushed-out, at a faster rate than that happens with compatible mixtures.
Many folks use the Honda
60 grease as is. I have NO problem with you doing that, works
so does Guard Dog 525, which I think you will like better. BOTH of these greases are fine with the
Airheads and Classic K bikes for the clutch splines (that is, the transmission input splines, as you do not
really put grease on the friction disc splines).
Classic K bike starter sprag clutch problems: For information, and the additives, and oil to use, see this article: kstartersprag.htm
Here's a somewhat long section, that gets into greases in much more depth:
The Honda 60 grease is sold by Honda car and motorcycle dealers as SKU08734-001, and you may find that the parts person will have to look it up, as he/she may not know about it. That part number is for the smaller 3 ounce tube. There is also a larger size available, often the car dealership parts departments know of the larger size.
I am intrigued by KRYTOX grease, but have not done tests....yet. I plan to test it UNmixed with anything else. Someone else is testing a version of Krytox, and I will report when I get the results.
Another grease that intrigues me, but I have not tested it for splines, is Ford's Silicone+Teflon based grease, Ford part number is D2AZ-19590-A. ....
That is replaced by Motorcraft XG-8-A; a small but adequate tube, not expensive either. I think it may have interesting qualities for transmission input (clutch disc) splines AND driveshaft parts.
There is also a military part number for the XG-8, and it is: MIL1167/31508-4207.
Guard Dog Moly (GD525), that I recommend,
is a 30% moly in a special base grease. The GD525 should NOT BE
USED if you do NOT THOROUGHLY clean off every last remnant of whatever
old grease you have been using, or the GD525 MIGHT NOT
stick well. GD525 is a soft light grease, easy to apply.
First: clean the surfaces with a good evaporating solvent using a brush. You have to
work the grease into the surfaces with a stiff small brush, such as a shorter
(cut) bristled 'acid brush'. I think that
GD525 may be the best grease I have ever tried for the input splines. It is also good as a general-purpose moly grease.
I am recommending
the higher percentage of moly and different base formula of
The following greases have also been tested:
Mercury Marine outboard grease works fairly well (Napa 18-9200). You can substitute Texaco Starplex 2 'with moly' (should be purchasable both with moly and without). Also, you can try Caterpillar spline lube: "Desert Gold Grease 129-1939, NLG1-2, with 5% moly."
Autozone sells a molygraph grease that has
had good results reported (But I haven't personally tested it).
BelRay has an Assembly Lube....which is also marketed by their industrial division as Molylube Antiseize 15.....There is ONE report that this stuff has been doing well at the splines. Has an aluminum complex base, 15% moly solids, supposedly GOOD at preventing corrosion and fretting and has lots of water resistance. No personal experience.
****Do NOT use moly greases in wheel bearings or in the steering head or swing arm bearings. Do NOT use moly greases in the throwout bearing for the clutch. A good rule of thumb is that moly greases do NOT work well in ball bearings, tapered roller bearings, and needle bearings. Moly tends to change to stiff flaky bits in those situations. As a general rule, do not use moly-containing greases, oils, etc., at any place there are anything but SLOW rotational speeds. Moly is GREAT for most SLIDING surfaces. Use moly grease on sliding splines. One exception to using moly is in the OIL of rear drives and transmissions, where a very specific liquid additive product from Dow Corning can sometimes be helpful, but do NOT use the concentration as printed on the container; more on this in other areas of this website.
The red Chevron grease I mentioned well above, withOUT moly, is particularly good for water vapor resistance; and, if you live in snow country, is excellent for those easy-to-wear-out universal joints on your 4 wheel drive truck. It is excellent for the BMW clutch throwout bearing parts (yes, I know that transmission oil will EVENTUALLY get to the area and lubricate, as intended), and pretty good for many places on your bike that need grease. It comes in standard grease gun tubes. You'll probably have to go to a Chevron distributor, not a gas station, to purchase it. You may have to purchase a box of tubes...so share with your Airhead friends...or, car/truck friends. While the Chevron red grease IS usable for wheel bearings, I prefer, slightly anyway, a different grease for them, but you could use the NLG2 for the wheels.
You could simply stock NLG2 Chevron EP Ultra duty, plus some moly grease and those would suffice for most all your greasing needs for your shop, bikes, cars, trucks. The exceptions would be where silicon grease is far better and petroleum grease should NOT be used; such as at rubber parts such as petcocks and for electric connections ...except battery terminals, where 'real' battery terminal protecting grease or even Vaseline (petroleum jelly) is OK. However, you will get better results using my recommendations in section 6 of this article, which includes this section too.
Moly grease may be available cheaply in "military olive drab colored pound cans", at your military surplus dealer or on Ebay. I am still using some cans of this stuff I purchased a long time ago, manufactured in 1966! For those anal enough to want to know, here are the main items printed on the can, and the name and number is: G353, GMD, Grease, Molybdenum Disulfide, MIL-G-21164B. MIL-G-21164B has later versions, at least to -D now.
*****Some folks have good results with using anti-seize compound on the clutch splines (AGAIN, this is actually on the transmission input splines ONLY, NOT placed on the clutch disc splines with which it mates). Since anti-seize also has anti-corrosion properties, this may, in fact, work OK...but I have NOT tested it for this purpose. My suspicions are, without the slightest shred of proof, that the NICKEL antiseize's would be good. I am STILL awaiting reports from those who have done that: bike model, mileage, condition of splines, blah blah.*****
One of the reasons that moly is used on sliding surfaces is that it bonds molecularly with the top layer of steel.
****NOTE: There is a special type of assembly lubricant used sometimes for camshafts and can followers. See my cams article.
****NOTE: BMW actually used a very high quality moly grease in the early Airheads. It is still my belief that this particular grease MAY be the very best, over-all. It was, then, called Molykote U, the present name is Molykote U-N. It is not cheap. It is over 60% moly disulfide, in a polyaklylene glycol base that is designed to slowly evaporate at elevated temperatures so that a mostly dry-paste is left. For the more nerdy, the thickener for the grease is a lithium soap.
7. For those of you with mechanical ignition with points, you can use any of the greases mentioned (without
moly) in this posting, but it is best that a high temperature grease be used; and Bosch does make the
proper greases: FT1V4 (5-700-002-005) just for the cam and cam felt and FT1V26 (5-700-005-005)
just for the automatic advance guide shaft. If you decide to purchase these, the small tubes will last you
the rest of your life. Ford also made a distributor cam grease (for felts too) number C4A2-19xxxx, but I
am not happy with that one. I have not tested many greases for this application. It is likely that any soft
non-fibrous wheel bearing grease will also work, as they should not melt and be thrown off easily. It is
important that the ignition cam be very faintly greased, as if it runs dry, it may squeak, and cause fast
wear on the ignition points rubbing block, closing the points. The inside of the ATU, the guide shaft,
also needs greasing. Bosch actually specified different greases for these places. Bosch revised at
least one of these greases, and has a new part number, which I do not remember at the moment.
8. While I feel that for the wheel bearings you should 'consider' purchasing a specific wheel bearing
grease, the Chevron NLG2 withOUT moly, as mentioned previously, DOES do a great job. The wheel
bearing grease I have had the best results with (extremely long shelf life, does not separate, is not
fibrous, and sticks and lubricates really well, and has decent water resistance) is Quaker State
Multipurpose Grease and Wheel Bearing Lubricant. This grease is a NLG1 type of grease, similar in
some respects to that red colored Chevron grease I mentioned...but different characteristics for these
purposes. It is NOT A MUST....but is what I personally use.
9. Heat sink compound: Likely the very best is the WHITE silicone type made by Dow Corning, type 340.
It is better than the other clear compounds for heat transfer. You can use Radio Shack heat sink
compound. You can also use common "dielectric grease" from your nearby autoparts store. The Dow
340 transmits heat very well. Silicone heat sink compound/grease is always to be used, smoothly,
thinly, evenly, under the electronic black box ignition module (clean off old stuff first), under the gas
tank. Clean and re-grease every two years to avoid problems. If the grease dries out, the black box will
overheat, causing ignition problems. ONE exception is the later RIVETED ones. The RIVETED
modules supposedly do not ever require re-coating.
If you are lucky, application of
will revive proper module operation. SOME silicone
dielectric heat sink compounds are clear, as noted the WHITE Dow Corning stuff is much better,
containing a zinc compound, similar to what we oldsters used to put on our noses at the beach, and the
white stuff conducts heat very well. If you don't want to purchase some, try begging a teaspoonful from
the local electronics repair shop. SEE #10 below, as if you have the clear stuff, it has other uses.
Clear silicone grease DOES work, the stuff may be called Silicone Dielectric Grease at the autoparts
store, and the reason it works ADEQUATELY, is that it is used in a VERY thin layer, whose purpose is
to fill in microscopic irregularities in the surface of the mating parts.
10A. Common clear silicone grease, light to medium thickness. Your autoparts dealership usually calls this
dielectric grease. Useful because of its wide temperature range and very long life and compatibility
with plastics, rubber, and everything else (generally). This is THE stuff to use...very sparingly...on the
O-rings you are installing in your carburetor, choke parts, petcock innards, and on electrical connection
plugs, unless you use Caig products, see 10B. LOTS of uses besides those. Even at the starter
motor Bendix drive (some moly's are fine there too on those SPLINES). GREAT for preserving rubber
parts, where the greasiness is OK. Silicon oil, in spray cans, is also available for preservative
uses....and for spraying into CLEAN and SHINY electrical connections, see 10B. Some use it on the
various rubber O-rings in such as the carburetor. It is VASTLY better than WD40. I am very much
against use of WD40 on electrical contacts.
10B. If you want the best product for electrical connections, the company that makes the best products is
CAIG. I don't use it on quite large power-carrying contacts, however, but it could be so used.
The BMW factory used a contacts/connections protective liquid before shipping the bikes. The
substance used was CRC 5-56.
product that I know of to SPRAY or otherwise apply in/on most electrical connection,
are certain Caig products. For those of you with K bikes, use the Caig products at the
computer brain connections...and, every other electrical connection. Caig invented the base
De-Oxit a very long time ago. It contains a chemical that BONDS MOLECULARLY with
metals. Common OIL/SOLVENT base type contact cleaners (INcludeds OIL types, even if
made for Radio Shack by Caig) at such as Radio Shack are NOT nearly as good, nor as long
lasting, as the chemical treatment Deoxit product from Caig. HOWEVER, they will work
adequately, IF you can abrasively (lightly for sensivite connctions) clean the connections first.
In fact, if you properly use the Caig products I recommend, a one-time application may be all
that is ever needed. Caig sells its products through distributors of electronics items, but you
can find them as Caig Laboratories, 12200 Thatcher Court, Poway, California.
http://www.caig.com/ 855-486 8388. NOTE that there are a number of different Caig products,
and some are simply a solvent mixture, with or without an oil.
Consider, if you can do it, cleaning contacts with a MILD abrasive, such as a shaped pencil
eraser, being VERY careful if the contact is gold-flashed. Apply Caig DeoxIT as the cleaner.
When done, apply Caig Deoxit GOLD. I do not recommend purely oil with a solvent, for contact
cleaners for motorcycles, that INcludes the Caig versions, sold by them or Radio Shack, of only
a solvent and oil. From either source, the Deoxit 5 is approved.
>>>>What about silicone dielectric grease, versus the Caig liquids/sprays?? Use the Caig products I noted above, on computer pins, and connections that are or are not generally exposed to bad weather or smog. For large electrical connections, I prefer the grease. The grease is messier. The grease, if used in moderate amounts, PREVENTS ingress of moisture. THE best is to use the Caig, let is stay on the surface awhile, then, withOUT removing it, add the grease, and assemble....or, add the grease after assembly.
FEW sealants are required NOR SHOULD BE USED on BMW Airhead motorcycles, except at a FEW very specific places.
HYLOMAR: There are several types of Hylomar. Hylomar was developed for Rolls Royce turbine engines, comes in squeeze tubes, and was originally used primarily on our Airheads to seal the cylinders to the engine block and the input threaded ring at the rear drive nose. It is different from common silicon rubber sealants, many types of those, and Hylomar seems to work, although NOT as well at the cylinder bases as other sealants....but Hylomar is exceptionally SAFE if a tiny bit gets into the oiling system. The tube will list a solvent for cleanup...I use acetone. When applying Hylomar I often thin it a little bit with acetone, as only a very thin layer is needed...a thick layer is NOT desirable!!! You can use a brush, and if needed acetone thinner...to ensure thinness of application, but do not leave brush bristles at the cylinder base, and keep the sealant out of the oil passageways at the top studs, put it around the OUTside of those top stud areas, not towards the piston side. Hylomar can be applied, allowed to dry, and then you can wait as long as you want before assembly.
Places that Hylomar, etc., were used include the threaded ring inside the nose of the rear drive and fork top and bottom caps threads. Those places are STILL good places for Hylomar.
Hylomar was THE sealant a long time ago for the cylinder bases, but my viewpoint has changed and I can NOT recommend it now for that purpose. I now recommend that you use modern silicon or other modern sealants, but very sparingly....see much earlier in this long article.
use Hylomar, and will continue to use it, for
the threaded ring in the nose of the rear drives and at fork caps.
There are other places you can use it, for sealing drain and
fill plugs, fork top caps, etc.
You can see Hylomar information at: http://www.hylomar-usa.com
Hylomar is a polyester-urethane product, NOT a silicone sealant. Hylomar sealants don't set up hard, and can be applied considerably in advance of when you need to assemble the parts.
Some have had problems finding
Hylomar. You can try at NAPA. The package has both the NAPA and Permatex logos and is called Hylomar HPF. The item number is
765-2682. It is expensive. HPF
is the same as the latest Hylomar brand version called
"Advanced"...it has NO solvents, and is very THIN.
There is also a RACE formula, that adheres better.
The more common Hylomar is now called Universal Blue. It originally was called PL32M or SQ32M when I first used it on /5 bikes. The M stands for MEDIUM thickness. There was also a L for LIGHT and H for Heavy. M worked OK then on Airheads. I don't use it anymore for cylinder bases.
The type of Hylomar I still am using, since I have a lot of it left, is the above old SQ32M, also under the Permatex brand as 25349. It is basically the SAME as Permatex HPF. I do not use it at cylinder bases.
Clean the surfaces really well, really degrease them.
Apply the sealant of choice VERY SPARINGLY AND AS EVENLY AS
POSSIBLE...AGAIN, SPARINGLY!!, If using Hylomar or Three-bond 1215, let sit at
least half an hour before assembly (this is important). DO NOT
block oil flow at top studs. Use any of these products VERY
sparingly for the cylinder base area, as they, or any sealant here, will almost totally
squeeze out, and you do NOT want the product in the engine,
especially not in the oil passageways that are at the top studs,
although Hylomar is a safer product if it does get into the oil
passageways, than many other...or most
NOT spread with a brush unless you will be careful to be SURE no
bristles are left....which can cause a leak by not allowing the cylinder to
fully come home to the engine.
HINT: DO NOT let the piston rod fall. It will nick the engine case, and the cylinder will not mate properly.
WHAT is RTV? RTV is shorthand for Room Temperature Vulcanizing (and usually means SILICONE). Most people simply regard them as very thick liquids that harden from exposure to air (even through the edge exposure of parts assembled together), and they 'turn into silicone rubber'. While that is not actually absolutely correct, it is good enough.
Some of the following is applicable to all types of sealants, and some, especially #9 & #13, is also applicable with common gaskets with NO sealants added.
a. There are hundreds of variations of RTV. They come in various colors too. Black is very
common, so is white. Versions for building and construction sealants come in shades of white
and brown and clear, etc.
b. Some types of RTV compounds used for gasket-making and other types are not truly silicones.
c. RTV's come in a variety of viscosities before they cure, and a variety of hardness's after they
d. For use on vehicles, in general, you purchase RTV in small to large tubes, like toothpaste tubes
they can be folded-up as you use them up. Industrially, and for building/construction/etc.,
uses, they come in quite large tubes that are applied using a holder that has a pistol-grip and a
plunger into the tube. An applicator tip is often supplied or the tip of the tube itself is used by
cutting, often on an angle, so you can 'lay a nice bead'. You probably have used such for
making smoothly curved sealing for weatherproofing your home, etc.
e. RTV curing generally starts as soon as you apply it from the tube.
f. RTV comes in two sort-of basic types that you will use on vehicles, etc. One type SMELLS like
vinegar (it is actually a type of acetic acid) and thus it is slightly corrosive to some materials
until fully cured. The other type has no appreciable smell at all.
g. RTV is extremely useful for making gaskets. Many engines, transmissions, etc., in modern
vehicles, have no paper or other types of gaskets, just a small bead or layer of some sort of
h. It is extremely important, when using an RTV, that every last bit of any old material be removed,
and, that the surface be completely clean when new RTV is applied. You can remove the old
material by chemical means and/or scraping. Use of gasoline, kerosene, etc., may do a fairly
good job of dissolving residue, but will leave a petroleum-based residue that keeps the new
sealant from sealing really well. I usually use acetone or MEK. Scraping should be done with
plastic or other material that is less likely to leave nicks, scratches, gouges. If you have to pry
things to get them apart, be SURE that there is no damage from this.
i. If fasteners are OVER-tightened, metal may mushroom-up, and prevent proper sealing.
j. RTV, and, frankly, most any chemical sealant ("'goo""), is good for only about 0.015" gaps,
maybe 0.020" at most. That is why you want the mating surfaces to be in such good, flat,
k. LESS is better than more...you do not want excess sealant getting into places it should not be.
l. When assembling the mating parts, be cautious about tightening more than a very minor
amount, until the sealant is in place for awhile. In particular, avoid torquing to final values
before 24 hours have gone by.
m. When torquing where there IS a gasket, such as the Airhead engine oil pan, be VERY cautious.
NO sealant is used, and if the pan is over-torqued, not only will you bunch-up the gasket, and
cause leaks, but you might go so far as to pull the bolt threads from the engine case.
In the above list, many of these things apply to ALL sealants; and, #9 and #13 applies to all REAL gaskets!!! REAL gaskets here means pre-cut hard gaskets.....like the engine oil pan gasket.
NOTE!!! Sometimes a sealant or other joint compound is used WITH a gasket, often such a gasket is made of some sort of 'paper'. DO NOT use but the thinnest layer of compound in this instance, and the surfaces MUST be very flat, smooth, nick-less. If a thick amount of compound is used, not only may the gasket shift during torquing, but excess may move inwards.
Cylinder base sealants:
I am no longer recommending Hylomar...for cylinder bases, although it has other uses.
The following are tested and "acceptable", but I am unsure of availability, this is old information:
Permatex 27B Hi Temp RTV.
Permatex Ultra-Grey ....some reports that it fails after a long time. It does seem to work OK if tube instructions are DISREGARDED; I suggest you apply very thinly in the normal manner, and allow all surfaces to set up a while, THEN assemble.
Pro-Seal Red 700 degree RTV 80726.
or Three-Bond from your BMW dealer are excellent. Three-Bond 1215 works well.
Allow time to set-up.
There is a sealant available at Suzuki dealerships, type 1207B, their part number 99104-31140, that some of the professionals really like. I think it's a good one, AND, I can recommend it.
Suzuki marine dealers, not just car dealers, sell it.
(1) After you torque the cylinder to the engine, some sealant, even if applied quite thinly and
certainly not excessively, will squeeze out. If you allow it to dry for a day or more, it is then
MUCH easier to clean up with a small brass brush, etc.....the excessive sealant just peels off.
(2) Most sealants require 'set up' for half an hour BEFORE assembling. THUS, the order of
events is apply sealant, wait,.... then oil the O-rings and assemble IMMEDIATELY, torque.
This waiting for setting-up does not seem to apply to the Suzuki sealant. IF you use Hylomar,
you apply it and wait for a few minutes minimum...but you can wait as long as you want to.
General sealants notes:
The places sealants are NOT USED INclude the engine oil pan; inner timing chest-to-engine; head gaskets; valve cover gaskets, rear drive gaskets; and driveshaft gaskets.
In a FEW instances, where a previous owner has messed up the surfaces of the mating pieces, Permatex NON-hardening Form-a-Gasket can be used, but this is to be done with caution, as gasket sealants can cause problems you may not think of, and repairing the surfaces is vastly better most of the time. Some areas should not have gasket sealants, to avoid the surfaces moving with respect to each other (called WALKING). This includes the junction of rear drive and driveshaft on Airheads.
SOME BMW gaskets are/were impregnated with a substance that activates after the surfaces get hot, and if you coat surfaces or gaskets with YOUR stuff, you will defeat BMW's intentions. This is/was so with the pan gasket and valve cover gaskets (on the head side of that gasket). I have seen plenty of these withOUT seeing any activating substance. Supposedly the coated ones on the valve cover gaskets are for the HEAD side. riiiiight! Be sure the surfaces are clean and dry. If you remove a valve cover carefully, without ripping the gasket, when replacing the cover, LIGHTLY smear engine oil on the gasket side that FACES THE HEAD. Eventually it will semi-bond to the head from repeated heating/cooling, and then when you remove the cover you are less likely to tear the gasket, and it can be used over and over!! NO oil on outer surface! I have seen valve cover gaskets on high mileage bikes that looked original.
It is critical that pan gasket mating surfaces be completely clean and dry. I use a strong relatively-fast-evaporating solvent. Allow no nicks at the metal surfaces that would give poor sealing. This is particularly troublesome at the cylinder base area & the engine case, where a dropped rod might put a tiny nick, that will keep the cylinder from being perfectly flat and going fully home; other places are the various covers, pry points, etc.
btw...when trying to clean off old gasket from aluminum parts, spray WD40 on the old gasket remnants, or a gasket remover solvent (autoparts stores), and use a plastic scraper, not metal, unless you are most careful.
NOTE!!.....For a short period of time, BMW did assemble rear drive CARDAN COVERS (that's the LEFT cover) using a sealant, and NOT a paper gasket. If you change to a gasket, you may upset the gear shimming.
JBWeld, JBKWIK, etc: These are popular epoxy materials that are available almost everywhere, and they DO work well. The -KWIK is good to near 300 degrees. Some folks won't go on a tour without a JBWELD-KWIK kit. With a small piece of 50 or 80 grit sandpaper with this kit, you can do an emergency fairing repair, seal a cracked valve cover, and probably even a cracked oil pan. Epoxy products do not last forever, so throw them out after a few years. NOTE that duct tape; or, better, radiator repair tape, is also excellent for a very quick emergency fairing repair.
Steel filled 2 part epoxy sealants: no specific place for these on your BMW, but they are very strong, and can sometimes repair a broken part that is unrepairable otherwise, rather than maybe heliarcing..etc. No need to purchase, just know about it. SOME folks have put the fast cure version of these in their bike kits, instead of the JB stuff. I have seen a transmission case and a broken valve cover 'welded' with this stuff. As with all epoxies, surface preparation and absolute cleanliness, never the faintest oil film, is the way to go. There are types of epoxies that are promoted as being able to repair THREADS. Some have had good results with these, after thorough degreasing, for such as stripped out aluminum drain plug area threads. I've had lousy results.
Weatherstrip adhesives: These are used on our bikes to 'glue' the ID strips along the engine sides, install fairing boots on RS/RT, etc. Common usage is to call this stuff by the name of Gorilla Snot, as they were originally yellowish, but black is now available. Several brands, but always purchase the 'SUPER' weatherstrip adhesive. I've had great results with Permatex, the black works well for RT fairing rubber boots (after degreasing the boots, use on the black painted interior), and the original: 3M (which long ago stood for Minnesota Mining and Manufacturing). ALWAYS follow the directions....this means doing it in two stages of application. This is nasty stuff, so keep it off your paint. It is VERY strong and does not release at moderate temperatures. Many folks use cyanoacrylate glues (Crazy Glue) at the fairing rubbers, but I have had it fail with age....see below...
3M also makes a Plastic and Emblem Adhesive, do NOT use it...it is not nearly strong enough!
Re: RT fairing rubber boots for the passage of the fork tubes:
I have not had the best results with most of the thin glues and sealants, they tend to harden and crack eventually and then the boot comes loose. LOTS of pressure on that boot, especially in lock to lock turns. If you use a cyanoacrylic (Crazy Glue or similar name), the rubber and the fairing area must be outrageously cleaned up first. Frankly, it is hard to do right, and I no longer even try using that stuff. Others feel it is fine. I use the same Weatherstrip Adhesive mentioned above. I clean the fairing area with a knife, inside and outside the opening, for maybe 1/8" or bit more. I sand it a wee bit. I then clean it with acetone. I have spent over an hour at times doing those things. I then clean the boot groove, and outside of the groove, with acetone or MEK...really thoroughly to remove every last trace of mold release agent. I then install the boot (there is a right and left, so don't install the wrong one, nor install it upside down...that has been done!). I install the boot with the adhesive generously applied to the groove, letting it overflow a bit. I clean up the fairing immediately with the solvent and a rag. Do not overdo this, the solvent eats paint. Probably isn't good for me, but I refuse to wear plastic gloves for this job. If carefully cleaned up RIGHT AWAY, it looks fine, if not, paint over it. I use my finger, dipped in acetone or MEK to wipe it smooth, before it dries, which is awfully fast. I am sure the solvents are not good for me. It is fun and games to put additional adhesive at the junction (after the boot is installed) INside the fairing. I usually make a bit of a mess, spend too much time cleaning, and then I paint it black with a tiny brush. The black stuff would be nicer inside the fairing. This stuff is truly STRONG. Its use is probably over-kill, and many get along just fine with CrazyGlue dabbed here and there on a carefully cleaned area of fairing and cleaned boot area. I have not had the best long term results with Crazy Glue, but it sure is vastly easier to use here. The ideal stuff might be a very strong adhesive in a hypo tube, but never looked into it.
First, an edited version of something I posted to the Airheads LIST, dealing with the exhaust pipe nuts. this is also going to be put into my specific article on those nuts. exhaustnuts.htm
While I prefer a nickel formulation; the Permatex and others, that ARE silvery in color, are OK. MANY seem NOT to know is that they DO HAVE COPPER IN THEM. You might have to look it up, might not be shown on the container, and, of course, might not have copper. The Permatex stuff I use now and then, does have it.
The main thing about any antiseize goop, and there are many types, is that what is important, except for specialty types that are only for a very specific or a few metals, is that the CARRIER in them is compatible with the type of heat we get at these nuts; AND, that you remove them, and then should use a mild wire brush (brass brushes my favorite here) on the threads and the one or two rings, to especially get rid of carbon and other hard things, and then slather on the goop, and assemble without overtorquing. Do it yearly. It is that carrier that tends to burn-away, or carbon up. That is a critical thing.
Note that the reason the nuts have been such a PIA, is not totally the lack of goop, nor is it unheard of for someone with good goop on the threads to find the nuts pretty well frozen after an actually reasonable period of time. There are things going on, besides the goop carrier and the goop's other ingredients, and besides dissimilar metal reactions. One is that the exhaust port and the threads is a place where nasty stuff accumulates. Some of this stuff is sulfur 'stuff' (or other compounds), and they react with moisture, yes I know the moisture is supposed to be instantly driven off my exhaust heat...it is not.....before slight damage is done. The compounds, with moisture, create acids. Acids have fun with the carbon, ETC., from the combustion process. NOTE that the atmosphere enters the threaded area from OUTSIDE THE NUT, from the exhaust header side of it. Atmospheric air has moisture, and 'other stuff'.
Another thing that is similarly happening is that there are often very faint exhaust gas leakages into the taper ring(s), the ring gaps, even when seemingly closed under pressure, and the gases bring carbon, etc., into any gaps in the threads...and as those gaps fill, the stuff acts like cement. Threaded things MUST have at least a slight gap or they won't assemble in the first place. BMW specifies a torque, which I think too high. On the other hand, too little, and the 'stuff' problems increase.....and WAY too little and the pipe moves.
As the threads get some wear (every time you unscrew the nut, there is carbon typically accumulated in the 'silver stuff', or any 'stuff'), it is somewhat hard, and wears the parts, and the thread fitment gets a tiny bit looser. This is particularly true in one area...yep, the first threads. Pay particular attention to cleaning them.
Back to the antiseize compounds:
Various types are available. They are a MUST
for the large finned exhaust nuts (You DO unscrew yours and clean
and recoat them and the rings there, yearly or bi-yearly??). I
like to use it when assembling ANY of the muffler system, even
the pipe joints. I believe it a MUST for spark plug
threads. This is MY feeling, not held by all, and not held by SOME spark
plug manufacturer's; and IS held by some engine makers, and not with others.
See my sparkplug.htm article for the finer details. I use it nearly all of the time on any
steel bolt that is screwing into aluminum; with certain STRONG EXCEPTIONS; steel bolts into aluminum hubs on wheels, holding the wheel to the hub. NEVER use it on steel bolts through those wheels into the steel hubs
or output of rear drive. That means do NOT use antiseize compound on the bolts on Monolever and Paralever rear wheels!!
In general, lower the torque on things by 30% when lubricated by antiseize compounds. This is especially so (in MY opinion) for spark plugs, and the 3/4 inch reach 14 mm spark plugs should not be torqued beyond about 15 foot pounds if antiseize is used. If you have a dual-plug conversion, the lower plugs are usually 14 mm and 1/2 inch reach, and they should have perhaps no more than about 12 footpounds of torque, which is JUST enough to flatten a fresh washer. There is a spark plug article on this website going into this in great depth. Antiseize compounds have some anti-corrosion properties. Some have used these compounds at the splines for lubrication, rather than regular greases. I wish these folks would report back to me.
Once an antiseize is used for spark plugs, it works into the
head metal, so continue using
it...don't go back to the higher original torque values. IN MY OPINION
DON'T WORRY about stories ...that SOME spark plug manufacturer's
tell you...to NOT to use the stuff, because of a worry about potential
for changed heat range. HOGWASH....does NOT happen on OUR type of spark plugs.
The BEST anti-seize is, perhaps, genuine 'Never-Seez'. Try to find the 'Pure Nickle 2600°' version. Nickel (the proper spelling) containing anti-seizes are the better types. http://www.neverseezproducts.com/purenickel.htm
is that the commonly available Permatex brand anti-seize is "not
quite" as good BUT IS OK for OUR needs. ALWAYS
have antiseize on hand. The common Permatex brand does
contain copper and nickel, it is the carrier medium in it that
disallows super high temperatures...again, it is OK!
I have NO problem with you using high temperature copper-containing antiseize compound.
PLEASE READ: sparkplugs.htm
Cyanoacrylic adhesives/glues: Often called by one of the original trade names 'CrazyGlue', and originally developed by the Eastman (Kodak!) company, these are strange 'glues' that are best for sticking your fingers together. Others may disagree, but this stuff is NOT always reliable, tends to get brittle and therefore crack, and has few places for use on your BMW. You may find uses for it, such as holding one of the damnable easy to loose ball bearings to its spring in the switch gear when you are working in that area, inside the instrument pod at the odometer gear-to-shaft (they tend to slip), RT fairing rubber boots as previously noted (I don't like it there), etc. I use it at slipping gears in speedometers.
LOCTITE....and similar anaerobic chemicals:
Do NOT use commonly available Loctite's for the speedometer or other parts where a metal shaft goes into plastic. Common Loctite is BAD on/for plastics, and it may cause cracking of the plastic. If you use a Loctite product, be sure it is compatible with plastics.
The most popular brand name for these thread lockers or adhesive/sealants is LOCTITE. I suggest you purchase a small size...and you might as well purchase Loctite brand, it is very commonly available at auto-parts stores. It is kind of expensive, but worth the money. This is a really strange type of chemical compound. They come in many grades and types, probably 99% of which are NOT stocked at your auto-parts store, and for which you will likely have no need. Some special types are for such as keeping bearing outer race shells from rotating or even taking up clearance from one that did rotate...and avoiding expensive machining. MANY Loctite products are NOT anaerobic!! Most commonly these anaerobic products are used to lock screws and nuts. The strange thing about these "sealants", thread-lockers, or whatever the word is that fits the particular application, is that they are NOT GLUES, but are activated by the ABSENCE of oxygen, and are therefore called anaerobics. The containers are made of a special plastic, that allows oxygen to get to the contents. Sometimes the contents will harden in the spout, mostly, however, I think those were older spouts NOT that same type of plastic as are the bottle bodies, which is why it hardened in the spout (most now use one plastic).....if yours hardens, simply use a needle in the spout. Do NOT store the plastic bottles in baggies!!
knowledge: These anaerobic compounds do
up the same way on various materials. Without getting into
ion exchange and other technical details, I ask that you simply
accept this information as true. It might surprise
you to find out that the setup time
(hardening time) is MANY times longer on aluminum-aluminum, than for steel into aluminum (or steel into steel).
Additionally: the values for strength, and a few other characteristics, are generally assumed in the literature (even if not stated!) to be for STEEL...and steel as it is received from a manufacturer...so it may or may not be exactly and totally and certainly NOT almost antiseptically degreased...you may not see a super thin oily film that actually exists. Most of the common Loctite's you will be using are tolerant of some light oiliness, some are specially made to be tolerant, like 263.
Loctite, and the other makers, further assume you are assembling the parts at 72°F
(22°C). These anaerobic compounds generally set up far
more slowly if cold; and keep in mind that the type of material, including any plating, affects the cure time. Loctite, and other similar
manufacturer's, may also not prominently
tell you on the package that they ASSUME, in SOME
instances, that YOU have specially cleaned the parts and coated
them with a Loctite activating primer. For
PRACTICAL purposes, for bolts of steel going into steel or bolts
of steel (plated or not) going into aluminum, and with the
threads clean and dry before applying Loctite, you SHOULD ASSUME that full and adequate strength will be obtained between 24 hours and three days. For most common purposes, and steel bolts into aluminum, near full strength is obtained...usually... within 24
hours. For use of the strongest products, like 270, 2701, and 263, the cure time to fairly good strength is likely to be 1 to 4 hours.
NOTE: these products get weaker as the temperature rises, and MOST have little strength left at 300°F (149°C). 263 is formulated to start loosing substantial strength at 360° C, yes, Centigrade. Be careful NOT to use a high strength Loctite, such as the ones typically colored RED; and ESPECIALLY grade 263, if you may want to unscrew the bolt without a considerable application of HEAT.
At the end of this article is a DISCUSSION AREA. I suggest you read it, as it covers more about Loctite.
Threadlocker #290 (29000), green. This is for small diameters, can SOMETIMES be applied AFTER assembly as it is very thin, and thus may creep into things, which it is designed on purpose to do. It has a medium low strength and the parts are held OK, but removable. NOT for heavy duty parts under real strain. I use this or the BLUE at the 4 enrichener (choke) screws on the side of the Bing CV carbs, and any other places for small screws or light holding strength. I have used the #290 at the carburetor fuel PIPE interface, but Blue or Red is stronger....but the 290 is fine if you do not yank, pull, push sideways that pipe, which on rare occasions would otherwise leak.
***There is a #222, purple, that is for use before assembly, and if you had to choose between #290 and #222, #222 might be better. You probably will not use this, shown here for your information. If you have some, it is fine for low torque applications such as on small instrument screws, etc.
#242. Medium to slightly higher strong, apply before assembly, parts usually still removable. Also called Blue, due to its color! Very commonly used. This is THE ONE you should always have on hand.
****Here are some places that #242 is used (not all are listed here):
Stud bolts for timing chain cover. M8 screw plug at front and 2 M12 x 1 screw plugs at side and rear of engine block that seal the internal oil passageway (some use RED for those plugs). Center pipe of the oil filter; fillister head screw at breather; oil pump cover screws; oil pickup bolts; POSSIBLY on the center 13 mm bolt going downward into transmission from airbox (on threads AND under bolt head...to prevent leaks) (I usually use non-hardening Permatex Form-a-Gasket myself at that bolt, as I worry about leakage of oil, not loosening); nut that holds the coupling hub in rear drive. I use it at the carburetor butterfly screws and the U-joint bolts at the transmission output flange. I use it in rebuilding transmissions, at the top screw that holds the baffle. BTW...I tend to tag that screw "do not loosen"....:-)
#271 and #272. These are VERY strong, with the edge to #272 because it has the highest temperature rating and cures fast. These really hold, and you WILL almost for sure need a LOT OF HEAT to be able to remove parts. **Do NOT use these unless you are SURE you will need to, and are willing to HEAT the parts to disassemble them. If you plan to have only 2 Loctite's, RED should be #2. I use red Loctite at the oil galley sealing plugs (sometimes Permatex Form-a-gasket PERMANENT version).
****Loctite #271 (for North American
markets). There is a 270 and a slightly improved version of 270,
called 2701, that is used by BMW on such as Paralever pins. They set up faster,
and are BARELY stronger. 263 sets up a bit slower, so you can assemble things over an hour or so. You can probably use common 271 in place of the
270 or 2701. NO guarantees by me (lawyer talk). Loctite discontinued 2701 from RETAIL sales, and might even ship 271 in place of
it. Be careful using these very high strength Loctite's as they OFTEN need
a LOT of heat to enable loosening the fitting. This is particularly so of type 263, probably you would chose it for ultimate safety for the Paralever pins and their nuts. It will not release without PINPOINT HEAT...a lot of it. Sort of the same for the old 270 and 271 and 2701.
NOTE: Snowbum uses Loctite BLUE on his personal bike's Paralever...yes, the bike with the sidecar attached! Snowbum HATES Loctite red at this location....it is way too difficult to remove the nut and pin. Snowbum well understands that BMW recommended 2701, and that the replacement for 270 and 2701 is 263. Snowbum thinks he knows why, it is lawyers, who worry over what could happen if the Paralever nut and pin loosens and the pin backs out. Snowbum isn't much worried, but he does use the lesser strength BLUE, and he DOES put paint marks on the housing, nut, and pin, to be able to easily see if they have moved. They never have. Snowbum is NOT the only person using 242 blue there, some BMW shops also do. I have personally never heard of a traceable problem.
When reinstalling fittings with fresh Loctite, it is BEST to remove the old hardened Loctite. That can be done with brushes or wire wheels and maybe acetone....in stubborn instances use common paint remover. In a few instances, you may have to use a tap or die to clean off old Loctite.
****#640. This is a special type used to hold such as previously spun outer races of bearings that have not deteriorated the bores too much. Very expensive, usually available in large containers only. I have this item if you need it. Free. You pay shipping both ways. It is used on airheads primarily at the /5 left side rear wheel bearing outer shell (race), where the shell has spun in the wheel, but the clearance is still reasonably small. I can supply details on its use.
Loctite products should be carefully used. Do not use them where they can creep into the rotating parts of bearings, etc. Allow at least 24 hours to cure, no matter what the manufacturer says. These products do NOT work as well if the parts are greasy, oily, or dirty.
I install most Helicoils with Loctite RED, wait for a full cure, then wash the excess out with strong solvents (and often a brass brush), before using a bolt in the threads.
***Loctite also makes Locquic's,
which are several
types of liquids, available in both concentrates and premixed, that will make Loctite 'set up'
quickly, or set up on difficult materials, such as plastics and some plated
metals. Used properly, you can be done with a job in minutes, instead of
waiting a day or more. Keep in mind that
MISUSE of these can cause the parts to seize before fully
Small tubes of Loctite can be stored a long time. If the spout clogs, use a common sewing pin to open the hole. Do NOT store Loctite in baggies! It MUST be stored where the air can reach it, that means no baggies, no tubes inside bottles.
For super-critical applications, a fresh tube of Loctite is recommended.
Occasionally a question will arise about proposed changes to a factory torque setting if Loctite is used on a bolt or screw, perhaps one that was originally specified to be installed clean and dry. Loctite is formulated to have only a small effect on effective torque (increases it ONLY slightly) so you can generally disregard torque changes, as Loctite does not act like a true lubricant.
However, for the especially nerdy, here is some technical information:
The clamping force, usually symbolized as letter "F", is really the force at the UNDERSIDE of most bolting situations, and the THREADS are there to ensure you reach that value, and keep it. Please re-read that once more! Yes, it is true that the HEAD to material SURFACE interface IS the CLAMPING FORCE. This is a simplification. IF, however, the head and material do not match and mate properly, then the holding force may well include a considerable amount of the thread force. Generally speaking, at least 4 fully engaged threads are the MINIMUM needed to ensure relatively close to rated forces and strengths, including ability for the threads to not pull out. Torque on a bolt is the product of multiplying a factor called "K" by the diameter of the bolt, usually called "D", by that force F. You don't really need the formula here, so it is not shown....but...K is a decimal, and T is in inch-pounds if D is in inches.
NOTICE that the force goes UP as the K factor goes DOWN. The relationship illustrates why a given torque value is more likely to break a smaller diameter bolt, common sense tells you that anyway!
For a CLEAN, DRY, NOT PLATED threaded steel bolt, nice quality threads, going into a clean, dry, NOT plated threaded steel hole with nice quality threads, the factor K is about 0.20. If the parts are faintly oily, K is about 0.15. You can simply use those as expressed as a percentage, if curious enough. NOTE that I said that force goes up with K going down. Thus, faintly oily parts have higher working torque, even if the applied tightening torque was the same. THINK about that statement. Think about BMW's last specification (BMW has had numerous ones) on the 11 mm flywheel (clutch carrier to crankshaft) bolts, 90 foot pounds and OILED! That is a LOT of force!!
Loctite type 242 (blue)
has a K factor of about 0.14 to about 0.15, having ABOUT the same
effect as if the parts were SLIGHTLY oily, and Loctite was NOT
then used. 242 is specially made to have a controlled
lubricity effect. BTW, type #272,
the strong and rather permanent Loctite, has a K factor of about
0.21. Think about these figures. Do you notice anything a bit strange? No? well, how about that the stronger #272 has a higher K factor, meaning a lesser increase in torque...hmmmm....
I do not know what the K factor is for others, I never bothered to look it up.
This all means that, theoretically, if the manufacturer had originally specified a torque with clean and dry threads and NO Loctite, that you should REDUCE the torque wrench reading by, perhaps, 15-25%, when using Loctite. This does NOT apply if the manufacturer SPECIFIED using such a sealant. I almost never reduce torque for parts to which I applied Loctite.
In practice, bolts are of sufficient strength, so no changes in torque values are normally used with Loctite. It is NOT clear to me WHY BMW did not specify Loctite BLUE at the U-joint bolts, but I definitely use it there, at 29 foot-pounds of measured applied torque. It may be that BMW counted on the discredited and NOT to be used split lock-washers that had been used on early models. Later on, BMW had a bulletin, to change the bolt lengths and eliminate the very troublesome lock-washers.
discussion of various methods of 'locking' screws, bolts, etc.,
is located in the HARDWARE article.
You probably will find it rather interesting.
Penetrating oils are generally used to free-up frozen screws, bolts, and nuts. Serious testing has been run on various penetrating oils. One of the best commercial products is Kano's "Kroil". WD40 is very poor at this job. PB Blaster is not all that good either. "Liquid Wrench" brand is nearly as good as the Kano Kroil. There is an aircraft liquid, MOUSEMILK. Don't bother.
I use a mixture that has worked very well for me and others: use just about any brand or type of automotive automatic transmission fluid, mixed with a good solvent. It tests BETTER than commercial products!! The solvent I used at one time was carbon tetrachloride, but nowadays I use MEK (methyl-ethyl-ketone, from any hardware store), or acetone (hardware store). MEK is sometimes hard to find, and Ethyl Acetate will work, and is often sold as a MEK 'substitute'. Ethyl Acetate is safer to use than MEK (Methyl Ethyl Ketone). Ethyl Acetate is a good solvent, and evaporates SLOWER than Acetone, and is excellent for working with fiberglas resins, some plastics as crack line glues, etc. If you were making up a penetrating oil mixture, I'd suggest 50% each of common red colored automatic transmission fluid and acetone....but if you substitute any of the above solvents for the acetone, it will work pretty good. Possibly the Ethyl Acetate is even better.
Acetone and MEK: Great fast evaporating solvents, keep away from paint!!! Keep away from plastics unless using for gluing cracks!!! Used for degreasing and some plastics gluing or glue solvents. Don't inhale fumes. Useful for cleaning some types of parts, including removing old hardened Loctite (in stubborn instances, use paint remover gel). When acetone is mixed with automatic transmission fluid, it makes a WONDERFUL penetrating oil. MEK is sometimes hard to find, and Ethyl Acetate will work, and is often sold as a MEK 'substitute'. Ethyl Acetate is safer to use than MEK (Methyl Ethyl Ketone). Ethyl Acetate is a good solvent, and evaporates SLOWER than Acetone, and is excellent for working with fiberglas resins, some plastics as crack line glues, etc.
Kerosene and Stoddart solvent (Mineral spirits), paint thinner, etc: good cleanup and parts solvents, relatively low fire hazard. NOT to be considered as an evaporating solvent for cleaning surfaces that need sealants applied to clean surfaces, etc.
Berryman B-12 Chemtool, in their particular version called "Carburetor and Choke Cleaner": The BEST spray stuff I've found for cleaning carburetor and carb parts. Still surprised the various controlling agencies have not outlawed this great stuff. Keep it away from plastics and paint! Next best thing to a formal carb cleaning machine. Also nice to use on those outside carb stains now & then. Many other brands of cleaners that I have tested are nowhere near as strong as this one. Be sure your can says, amongst its other ingredients, that it has acetone and MEK (methyl-ethyl-ketone) in it.
***As noted previously, now removed, California regulations have caused the Berryman sold in California to be reformulated. The California reformulation is nowhere's near as strong now.
If your B-12 Chemtool has numbers 0113C; 0117C; 0120C; or 0152 on the can someplace, it is OK for general use, but not for serious cleaning of such as carburetor passages. The 0113; 0117; and 0120, are much better.
Brake fluids: Use ONLY DOT3 or the slightly better DOT4. Keep it OFF the paintwork, and keep a VERY WET RAG on your paintwork when working with it..... If, HORRORS!.. it gets on the paintwork, wash it off with water, INSTANTLY...that means RIGHT NOW! ALWAYS have a WET RAG instantly available when using brake fluid! When I bleed brakes, I keep a very wet rag below the master cylinder.
NEVER use DOT 5 silicone fluid in your BMW braking system...NEVER! DOT5 silicone fluid does not absorb moisture, allows moisture to condense into droplets in your braking system and thereby probably rotting it out faster; and, it can, in freezing weather, FREEZE the brakes!. Silicon fluids are not really compatible with the rubber parts in your bike's braking system (some may be compatible, depending on when manufactured). There are premium DOT4 fluids; and, confusingly, a 5.1 that is NOT silicone based;...these generally have even higher boiling points (Castrol for instance)....that are just fine, but the RACE types MUST be changed AT LEAST yearly. I recommend inexpensive DOT3 for most folks, with DOT4 for those who are hard on the brakes. It is entirely possible that some BMW systems ARE compatible with DOT5 silicone fluid, but BMW says NOT to use them. Some have used them for long periods of time, successfully. The big problem is that SOME brake rubber parts are NOT compatible, AND, it is near impossible to clean the old DOT3 or DOT4 out, without a total rebuild. SO, I HIGHLY recommend AGAINST DOT5 silicone fluid....which have almost no advantages for airheads.....(it is thinner, so maybe easier to bleed on an opened system) (but tends to get tiny bubbles, defeating that idea)....and won't absorb water...but water gets inside from various means, and forms globules, and corrodes the parts! At very elevated temperatures, totally possible in our airheads brake parts, it gets compressible!..a BAD thing.
There is a fluid called DOT 5.1; confusingly it is NOT a silicone. DO NOT USE IT. If you insist on using it, or a 'race brake fluid'; change it every 6 months, fully flushing/bleeding....and ONLY ONLY ONLY from a fresh can.
DOT3 and DOT4 Brake fluid need yearly changing, as they attracts moisture, right through the non-leaking lines, caliper seals, screw holes at the covers, etc. Bleed the brakes until clear fluid comes out. Best to use a fresh 8 ounce can each time. If you do this, you are UNlikely to EVER have to replace the master cylinder or calipers. If you DO open a system, NEVER EVER use anything but brake fluid in cleaning.
The truth is that if an 8 or 12 ounce can is
opened, used, recapped immediately, it will still be OK. NOT if it changes
Fuel Tank sealants &
Fuel Tank Repairs:
See well below for how to treat your tank and also aluminum, with etching stuff.
www.gas-tank.com/bike.htm This is Moyer Fuel Tank Renu. Every sort of fuel tank
repair for any vehicle; even the worst possible condition tanks can be repaired, and
lined so they never rust again. 1-800-328-9550 2011 Western Ave., Greensburg,
Pennsylvania 15601 Moyer@westol.com
Will repair K bike and other aluminum fuel tanks. www.advancedwelding.info
located in Mountainview, CA
John Borella 860-774-5535
Holt BMW in Ohio does tank work....740-593-6690
The above list may not be up-to-date, so see my references article.
Fuel tank sealants:
KREEM: NOT recommended.
POR15 rustproofing coating: see internet for sources. Requires a lot of
preparation work, but it is worth it to do it THOROUGHLY.
Read this: http://www.mklsportster.com/Articles/mcn-por15.pdf
Damon Products Red-Kote
Radiator shop's "Red Kote" jobs are usually much
cheaper. www.damonq.com/red-kote.htm You can do the Red-Kote job yourself.
www.4secondsflat.com/ click on the left side list for tank sealant. I have NOT,
purposely, shown the full URL to get to the specific tank sealant page, because
their website has faulty links internally.
A premium product, with somewhat less serious prep needed.
FUEL ADDITIVES: Only two I can presently recommend, & these are for storage purposes:
Startron Enzym type, such as from Amazon.com or PowerSportsSuperStore, etc.
Stabil, but get the proper type for your application.
STEEL FUEL TANKS....and aluminum parts:
Aluminum door and window frame cleaners (hardware store item): Clean the outside of your aluminum wheels, engine, carbs, etc...any aluminum or magnesium...with solvents, and detergents, washing well...and water...then, while still wet, apply this stuff, but do NOT let it dry. If it starts to dry too early, use more. Hose off. Keep it off your skin. Some use it for cleaning aluminum cases and covers. FAIR at this.
***When touching up painted steel surfaces, and you have rust areas, do fine grit sanding and feathering into the 'ok' paint area, and then treat the area to either a metal etching liquid from the local hardware store (it contains PHOSPHORIC ACID, and will so state on the container), OR; for surfaces where the liquid would flow off, use a similar but gel product called Naval Jelly. Naval Jelly usually works reasonably quickly. The screen door and metal etch stuff will work fairly quickly, but I usually use it diluted 1:1 with water, and let it sit overnight. I do this for the bottoms of fuel tanks, after the tanks are well-hosed-out with warmish water and a bit of detergent, then flushed well. These phosphoric acid products CONVERT the RUST, even HIDDEN rust at the edge of paint, to an iron phosphate type stuff that is grayish-blackish and is PROTECTIVE. Do NOT sand that off, only WASH the acid product off. Let dry, repaint your rusted frame area you just fixed (flat black...matte black...).
****Cleaning a fuel tank that has nasty very old deposits of jelled or dried gasoline, etc., in a bottom layer:
I recommend using a variety of solvents, letting each one sit numerous hours. Start with REAL
methanol; then use isopropyl alcohol; then REAL MEK; then acetone. Then, see next paragraph:
***Sometimes I am asked how to go about
cleaning and pickling a fuel tank. Wash with a water hose and sharp spray,
full strength, after removing petcocks. If anal, wash again
with a strong solvent, then wash with water again. Plug the petcock
holes with 1/2" tapered corks from the hardware store. Pickling the tank
is only needed at the bottom. 16 ounces of the etching product (MUST
contain phosphoric acid) is enough. Pour half into each side of the tank.
Jiggle the tank. Let sit a full day or 24 hours or so. Remove acid,
wash tank very thoroughly. Drain tank as best you can. Turn
tank upside down when it seems empty, tilt to one side, then the other, then
drain again. Put tank UPSIDE DOWN, with some sort of small support piece,
over your floor heater outlet vent....one that does not get too hot to put your
hand on it. The heater output must go through the tank refueling opening,
and then up, circulating in the tank, and out the two petcock place holes.
A day or two, and it is dry. If you do this every 5 years, and
maintain your tank full or nearly full, when parking overnight (especially high
humidity places), you will likely not ever have the bottom rot out.
Black Plastic items: Faded luggage and other faded parts can be somewhat renewed to look much better with a variety of protectant treatments, such as Back-to-Black, and many others, including Armor-All, Boeshield 303, MANY others. In general, the treatment does not last very long. Repainting is a PIA! Mild abrasive rubbing and then coating with one of the mentioned protectants, is a PIA! I do NOT have a really good fix.
Glycerin: BMW used to recommend using this, and then a bit of talcum powder, on your fairing pieces rubber molding separators and some other rubber items. Good, but other products, like silicones such as Black Magic, are also available. Don't even think about products like these for your tires.
***BMW use to sell (still??) a product called Gummi-Pflege, for squeaky RUBBER, and as a protectant. 82-14-9-407-015. Was a tube with a foam top for applying. It's purpose was for such as car door rubber flap seals, etc. A good substitute is Zymol Seal, which is made from modified Glycerin.
I say: Don't bother!
REAL tire lube and REAL tire talc: MUCH better than most substitutes. REAL tire talc has NO oils. Purchase tire lube and dilute per instructions and put about 6 ounces or so in a flip top 8 ounce plastic bottle. If you use tubes on your motorcycle, carry both diluted lube and talc with you, just the lube for tubeless owners. Yes, it IS true that 'personal lubricants', water based, work OK.
useful, with some sort of glue, as an emergency
sealant for a ripped/torn carburetor diaphragm. I don't know what type of
glue to use, since I have other uses for condoms, and never have used them for
carb repairs, since I never let my carbs go over 60,000 between changing
Radio Shack electrical contact cleaner: Use sparingly, perhaps on a Q-tip, sometimes spray. OK for cleaning electrical contacts and keeping them operating longer. If the contacts are REALLY grungy you may well want to use a stronger cleaner first. Finally coating with the clear silicone grease is good. There are much better contact treatment products, rather pricey, Caig brand is the very best....and was described earlier on this page. When using any type of electrical contact cleaner, mechanical abrasive cleaning is done first if at all possible. I do NOT use mechanical sandpaper methods if the contacts are gold-flashed. I use an old-fashioned typewriter cleaner 'pencil'...the abrasive is plenty strong, use sparingly, on other types. Regular lead pencil red eraser works good on plated pins, and is safe.
NCP2: This is goop in a tube that STOPS corrosion at the positive (+) battery terminal. I feel this is a necessity, and even nice on the sealed batteries...and should be applied to just cleaned and shiny tight connections at the + terminal, and forced up into the + electric cable for half an inch or so. VASELINE will do OK. SOME folks use silicone grease. Apply the goop AFTER the wires and nuts and bolts and washers are assembled and tightened. You DID have those parts clean and shiny BEFORE assembly???
WD40: Heavily promoted, but I dislike this product. It tends to gum up eventually. Some find it very useful for softening labels for removal, removing dead bug splats, etc.
Home rubbing alcohol, isopropyl alcohol, any strength, home type or stronger drug-store special type: fairly mild cleaning agent, but keep off your plastic stuff like taillight lenses, windshield, etc. Seldom ever used. Some folks DO use it on their windshields just prior to putting some sort of rally sticker in place. Probably OK, but a FEW types of plastics dislike it. Don't have it in contact with plastic very long.
Tape: Instead of carrying a small bit of a
roll of this in your bike's tool tray, consider a small roll of
the better Radiator Repair Tape. There are glass fiber
reinforced Duct tapes and Radiator Repair tapes.
Engine Coolant: Many of you have K bikes, and other bikes with water cooling. Please read the following article that covers coolants, IN DEPTH: k-coolant.htm
WARNING! This is a VERY important caution....never, EVER, EVER, expose Brake Cleaner or any other chlorinated hydrocarbon to high heat. The reason is that high heat may create the intensely serious poisonous substance called PHOSGENE. Bad things have happened when someone sprays such solvents on a part, and then uses a torch flame on the parts. This means that you must NOT clean brake parts with brake cleaner and while still wet use a torch to burn up deposits.
Cleaning old gunk out of brake system master cylinders and calipers: Use Brake fluid. Mix with water and detergent. You may have to let it sit a week. Clean with hot water and detergent, drip dry, then clean with fresh brake fluid.
NOTE!....The alloy wheels are painted. An EXCELLENT match for that paint is Würth's Silver Wheel Paint.
This is an area for somewhat disjointed ramblings.
****A discussion of various methods of 'locking' screws, bolts, etc., is located in the HARDWARE article. You may find it rather interesting.
In January of 1983, BMW came out with Service Information
Bulletin 00 029 83 (2068) covering adhesives and
sealants for use on BMW motorcycles. This bulletin is
somewhat out of date, but still useful. It describes various
types of products, and listed where these products are used on
our motorcycles. I will duplicate the information
below, with some personal notes added
1. Products described:
Loctite 242, medium-firm thread retainer, color blue This is a controlled lubricity product, very useful.
Loctite 272, high-strength keeper and retainer, green. This is now RED in color, and fast setting, and
has a fairly high temperature rating. It will NOT release without heat...sometimes a LOT of heat.
Loctite 495 Super Bonder, transparent. This is sort-of like Crazy Glue.
Loctite 515 Surface sealing, color green. This is now PURPLE in color, and is a gasket-eliminator
product, which has a characteristic of remaining flexible.
Loctite RC/601 and RC860: these are obsolete joint seal products, originally green in color. BMW never
identified, AFAIK, where to use Loctite RC/601. BMW said to use Loctite RC/860 at ONE place. Note
the reasoning! BMW said to use this joint seal compound at the "flange joint between rear-wheel
swinging arm and universal joint housing on R80G/S (absolutely essential as an additional safeguard
against twisting in this joint, and to seal the joint face)". I am not convinced for most riders.
Places products are
Loctite 242, blue: Shouldered nut retaining the coupling hub at the pinion in rear wheel drive, to secure the nut. BMW also said to use it at the lower part of the air cleaner at engine and gearbox, and under the bolt contact face to prevent air (and gearbox oil) leakage. I say NOT TO use there, only at that shouldered nut, and to use Permatex non-permanent Form-a-Gasket at the 13 mm vertical bolt in roughly the center of the airbox. Other OK places to use 242 are the 2 stud bolts in the aluminum for the timing chain cover; the M8 screw plug at the front and 2 M 12 x 1 screw plugs at side and rear of engine block to seal oilways (or use RED); the INNER, IN ENGINE pipe threads in the center of the oil canister if the pipe comes loose (I use RED); the 3 x 8 fillister head screw at the breather to secure the diaphragm spring (those models with such) and baffle plate to breather valve body; the 4 M 8 x 18 hex bolts for the oil pump cover; and, lastly, the 2 hex bolts for the oil pickup dome on the engine block.
Loctite 263 or 2701 or 272, red: Stud bolts in aluminum, in the rear wheel drive for attaching to the swing arm; spring strut mounting lug to the damper piston rod (rear shock stud to upper retainer); and, finally, the pivot pin for the gear shift pedal at the footrest (frankly, I do NOT use it there). Paralever pins threads and locknut. Frankly, I do NOT use these on my own Paralever pins and locknut. I find them WAY too strong. I use a small amount of BLUE Loctite. YOU use what YOU consider safe for those Paralever parts. If you use blue, you are responsible, not me, and do at least put a bright colored paint mark on the parts to be sure they are not loosening....and inspect the marks regularly.
Loctite 495: BMW said to use it on knee pads on tanks and twistgrips. A later bulletin (32-003-85, 2159) says to use Loctite 496. Frankly, most folks simply use hairspray to install twistgrip rubber.
all previous revisions; update information on oils and greases in
line with the latest information; edit entire article and release
01/10/2007: add more information here and there. Add fork oils viscosity.
01/25/2007: rework item #12 with latest information
01/16/2008: combine from some of 52B, and renumber from 73A to 73
03/14/2008: update information on 270, 271, 2701, and a few clarifications elsewhere's
06/25/2008: Revise #4; minor editing elsewhere's
09/14/2008: Revise entire article, mostly to add additional information.
09/26/2008: Add info on Honda moly grease part number from CAR dealerships.
06/29/2009: minor updates, combining some things that were redundantly repeated, clarifying some
details here and there.
01/25/2010: Add hyperlink for anti-seize
08/06/2010: Add #19 and re-number
12/16/2010: Phosgene warning
10/01/2011: Links to hardware article regarding locking methods
10/13/2011: Slight updates for clarity
11/16/2011: Clear up the Honda, Moly, Guard-Dog, and similar areas.
09/23/2012: Minor editing. Add QR code; modify Google code; add language button function (language
code removed 2013)
02/25/2013: Emphasis added here and there. Minor clarifications. No substantial changes anyplace.
04/14/2013: Revise to eliminate several duplicative areas. Clarify a few details. Update a few things.
12/09/2013: Revise slightly for Loctite 263 addition, and cautions, etc.
01/30/2014: Update the silicone-ptfe grease part numbers info.
02/18/2014: Revise #6 extensively
03/01/2014: split #10 into 10A and 10B, and revise wording. Eliminate #19.
05/10/2014: Update info on Berryman's.
07/30/2014: Add CRC 5-56 information
08/06/2014: Add more moly information
08/16/2014: Expand general statement on sealants and RTV desc. and usages.
09/23/2014: Fix for better use on smaller devices. Re-arrange entire sections on sealants into one.
More work needs to be done to make things neater.....did so 10/2/2014
10/05/2014: Add information & link for kstartersprag.htm
10/11/2014: Re-write 10B to clarify Radio Shack and Deoxit by Caig.
11/07/2014: Expand the antiseize section re: finned nuts
© copyright 2014, R. Fleischer
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