Section 7, Lester Wheels
This is article 54,
Lester cast alloy 7 'spoke' wheels were a popular aftermarket modification for BMW motorcycles a long time ago. Lester made them for the front and the rear. Lester also made wheels for many types of motorcycles, bicycles, etc.
Lester wheels can have problems. They were not well
put together inside the hub area right from the factory, and the wheels have a
disturbing tendency to get stress cracks (no nasty potholes
needed); or worse; around the hub, and elsewhere's.
These wheels also do not have the safety-rim 'bumps' for use with
If you are servicing your Lester wheels, and you find just a piece of water pipe inside for a spacer, you REALLY should install the BMW parts.
Lester wheels were well-known by most Airhead master mechanics to have improper preload shimming (there were no actual changeable shims). Too tight and the bearings overheated, sometimes with disastrous results. Some wheels cracked. My understanding is that Lester was sued out of existence.
Lester alloy wheels probably should NOT be used in tubeless mode, as they do NOT have a safety bead for the tire to hump over, which tubeless rims do. Many have, however, run them safely as tubeless for huge mileages, with NO problems....in the same way as many with the BMW Snowflake tube-type wheels have used them as tubeless. There is an article on this website about that: Section6.htm
MOST Lester wheels as used on BMW Airhead Motorcycles originally came with one pipe spacer inside, and no good method of adjusting the bearing preload. Yes, Lester did not shim the wheels properly.
If you have that single internal pipe, I highly suggest you
install the BMW parts, which have a shim, rings, and a longish spacer.
These are probably the correct numbers:
Plastic sleeve...you need two...36-31-1-237-595
36-31-1-235-785 (might be 36-31-1-238-785, don't remember)
shims (wedding bands) as required.
The process is QUITE similar to the early wheels in which one inserted the axle from the drum side, and heated the hub, and withdrew all the items out of the hub. WHAT you do with the contents, and the seals, etc., all depends on what you find inside your Lester wheels.
Heating the hub is absolutely required to install or remove
the bearings, etc., as there is no steel
insert cast into the wheels. About
You can remove all the innards by having it all together, cap cover removed, and insert the axle FROM THE DRUM SIDE, add a piece of pipe to take up the distance from the outer bearing to the threads of the axle. Tighten moderately, then HEAT the hub, I do it on a hot plate, and when pretty darn hot, I use a brass hammer LIGHTLY on the axle on the brake side, and it all comes out. Thereafter, when you have installed BMW parts, etc....you do the wheel bearings just like early BMW innards, because they ARE. Remember that you must re-heat to reinstall the bearing assembly. I chill the innards in a freezer, and install quickly, on a hot hub. DO NOT hammer anything when reinstalling!!!!
If you have Lester wheels, they must have the wheel bearings serviced just like any other early BMW wheels, which means cleaning, lubricating, new seals, and...of course....checking the preload on the bearings. The preload is VERY important on Lester wheels, due to the LOUSY Lester internal spacer, which is fixed in length, and which is not all that stable. Install BMW parts!
The bearings are the same BMW bearings as in the other models (before 1985, that is), they are #30203. That is a very common bearing, at any bearing supplier, or your BMW dealership.
Besides the tendency for cracking, the main problem is that Lester did a lousy job on what they put INSIDE the hubs, and you may well find almost anything inside yours!
If you intend to continue to ride on Lester wheels, at least inspect them now and then in the hub area, and especially after any serious pothole, etc., events.
If your wheel has side play, or too much bearing friction, you are highly advised to fix these situations!!
For a relatively easy way to install the parts as used on the 1970-1978 BMW motorcycles, adjusting the shimming withOUT the need for special tools, see Duane Ausherman's website.
I have other articles or links to articles that
explains some of what you need to know, and references some
previously published articles:
In order to work on Lester wheels, be SURE to read ALL of these articles; and see other subsections of section 54 on the list of technical articles, the links are below.
This is an UNEDITED copy of a posting to the Airheads LIST on 09/04/2013. I was in contact with this gentleman some months previous to this posting, and we had several E-mails back and forth, and I also contacted Craig Hansen. At that time I do not remember the slightest word from Mr. Nast that this wheel was a LESTER wheel. I am sure that many of you know that Lester wheels have had problems. Not getting into that here. I do note that Mr. Nast was quite unhappy with Hansens BMW in Medford Oregon, as he felt (my words here) that they did not back up their warranty sufficiently....wanting HIM to pay for re-riveting. He contacted me, and I never did receive the full information on what was going on with that wheel. I did not know it was a Lester, he left that out in all communications with me. He did not, apparently, re-contact Hansens after the second riveting.
The website you are reading this on, mine, contains an article describing how the splined cup can be replaced using bolts. I did not develop that procedure, it was done by Oak Okleshen, a noted Airhead Guru.
I make no additional comments on the below verbatim E-mail from Mr. Nast to the LIST.
""One of my bikes is a 1978 R100/7 with Lester wheels. Hansen's repaired the final drive splines at ~ 100K, and riveted a new coupler onto the rear Lester.
About 20K later, I noticed a rivet had fallen out. Hansen's stated that all rivets should be replaced, which they did, at my expense.
About 20K after that, I noticed spline grease on the outside of the wheel. Pulling the wheel, I noticed that the coupler was loose. It could be rotated a bit, and rocked a bit. Could this be why there was a strange clicking from the back (noticeable when coasting with the engine off)? The grease was escaping through the rivet holes. So, the rivets
had failed again. Time for another plan.
After reading all I could find on the web, I was satisfied that bolts would work, but I was not confident about the details I read. Here's what worked for me; it's holding up well. There may be variations for stock wheels.
First, I removed the old rivets, using a mill. The rivets were pretty worn where they passed though the coupler, btw. Next, I milled a true flat spot for the bolt heads on the wheel. On the Lester, there is a slight slope in the casting where the rivet or bolt head would be. Probably OK for rivets, but not for bolts. I also milled in a slight chamfer, because the bolts have a little extra material where the shaft meets the bottom of the head which require clearance. Next, I milled true flat spots for the nuts on the coupler. Again, there is a slope (more than then wheel had). The coupler steel is tough, you need an expensive end mill here. In a couple of spots this removed a little metal from the outside of the splined area, which didn't bother me -- the coupler is still plenty strong, and now the fasteners will fit the way Orville Wright intended.
For fasteners, I used MS21250-04008 bolts ($3.70 each) and MS21042-04 nuts (cheap). The bolts have a half-inch "grip" (unthreaded shaft) and half-inch thread. This is a different size than Snowbum specifies. A good table of milspec bolt sizes can be found at <http://www.gen-aircraft-hardware.com/images/pdf/ms21250.pdf>. No
washers were used, or would fit. The milspec fasteners were sourced from Spencer Aircraft in Puyallup 1.800.424.1160. Note that you will want some 5/16" (or 8mm) 12-point sockets for assembly; these are surprisingly uncommon.
Because I removed the least amount of material possible and there are casting irregularities, there was a variation in how far the bolts protruded through the coupler of about 1.75 threads. The bolt shoulder must pass through the coupler, but not beyond. The simple expedient was to cut any additional thread needed with a die (1/4-28). About six of
the ten bolts are custom fitted in this manner -- the rest fit without modification. Sounds like a lot of trouble, but this part went quickly. Assembled using blue Loctite, torqued to 120 inch pounds. The excess thread above the nut was removed with a cutoff tool, and touched up with brushed-on gold brake caliper paint to fend off rust.
So far (500 miles), the repair is holding up perfectly. Hansen's respline is also holding up well, with no noticeable wear in ~45K. The clicking I heard in the back is now gone - it was the coupler tapping the wheel. The only downside to this procedure is the time involved -- if you're paying a machinist, a new wheel might be cheaper (though good
luck finding a new Lester). Those 12-point gold cadmium-plated heads really do sex up the wheel, even if my neighbors have not lined up to admire them.""
11/23/2004: minor, for clarity
01/23/2010: minor clarity and emphasis changes
04/10/2010: Minor clarifications, and then add hyperlinks.
06/20/2011: slight updating
10/09/2012: Add QR code, add language button, update Google Ad-Sense code
04/15/2013: Redo for additional clarity, and add part numbers.
09/04/2013: Add section with E-mail from Mr. Nast, and my comments.
© Copyright, 2013, R. Fleischer
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