1993 R100R Questions

[sarelp]

Hi everyone, I just have a few stupid questions and I would appreciate some help please. My bike is leaking oil from the front boot on the final drive. I removed the swing arm and there was a lot of dirty oil coming out of the housing, my clymer manual states that the drive shaft has it own oil supply ? I assumed it was the rear output seal on the tranny. It does show signs of clean transmission oil on the outside.
How much oil is suppose to be in the drive shaft housing and where do I put it in??
I then dicided to pull the tranny to lube the splines, btw they were bone dry. Could this be my down shifting problem that I havent mentioned yet?
My other question is about the circlip in the tranny, is there a way to find out if it has it in or not without disassembling the tranny?
I tried to search this and other forums without much luck so any help would be appreciated. I would also like to see some picss of a flange holding tool (homemade) if anyone has one, please.
Thanks.

[mneblett]

My bike is leaking oil from the front boot on the final drive. I removed the swing arm and there was a lot of dirty oil coming out of the housing, my clymer manual states that the drive shaft has it own oil supply ? I assumed it was the rear output seal on the tranny. It does show signs of clean transmission oil on the outside.
How much oil is suppose to be in the drive shaft housing and where do I put it in??

How much oil in the swingarm? None.

Your bike is a Paralever airhead, based on the Paralever R100GS -- bearings on both ends of the swingarm, and a bar under the swingarm to hold the final drive housing at the correct attitude.

Clymer is referring to the Monolever '85-'95 airheads, which have the final drive rigidly bolted to the end of the swingarm. The Monolever contains a bit more than 100 cc of gear oil, and has fill and drain plugs on the forward end of the final drive casting, next to the swingarm bolting flange.

Oil in a Paralever swingarm comes from one of two places: leaking forward from the final drive housing through the front pinion seal, or leaking rearward from the tranny through the output shaft seal.

No easy way to tell which -- you can loosen and pull back the front rubber boot, but if it's not dry, you likely won't be able to tell whether it's the output seal due to the potential for the in the swingarm to be thrown about while you were riding. Pulling the swingarm and looking close at the seals is the next step.

I then dicided to pull the tranny to lube the splines, btw they were bone dry. Could this be my down shifting problem that I havent mentioned yet?

Could very well be (bad shifting is a classic dry splines effect), BUT, without riding and/or a more precise description, over the Internet no one can tell you for sure. If a high miles or heavily abused tranny, bent shift forks or shift mechanism damage could also cause problems (as well as other possibilities). Best bet is to drive the bike with the freshly-lubed splines to see whether the problem is still there before tearing into the bike again.

My other question is about the circlip in the tranny, is there a way to find out if it has it in or not without disassembling the tranny?

Sorry, unless you have a receipt from a shop or airhead guru documenting installation of the circlip, you can't know -- and your bike is well within the no-circlip range. As a related question (and potentially related to your downshifting issue) -- when you had the tranny out of the bike, did you rotate the output flange by hand? Did the bearings feel perfectly smooth, or was there any roughness in the rotation?

[sarelp]

Thanks for the reply,

As far as the drive shaft description in the Clymer manual should I treat it the same as a R100GS? The output seal on the transmission is pretty wet so I'd say thats where its coming from.
When I was riding the bike it shifted up perfectly but downshifting from 3rd to 2nd and 2nd to1st was kind of hard and I had to release and pull the clutch lever in a second time in order for it to shift.
With the transmission on the bench the output shaft does not turn as smooth as I expected it would, BUT it shifts up and down like it should.

[mneblett]

As far as the drive shaft description in the Clymer manual should I treat it the same as a R100GS?

Yes -- same basic components, with a shorter spring/shock strut.

The output seal on the transmission is pretty wet so I'd say thats where its coming from.

Likely.

When I was riding the bike it shifted up perfectly but downshifting from 3rd to 2nd and 2nd to1st was kind of hard and I had to release and pull the clutch lever in a second time in order for it to shift.

Again, likely due to the dry splines (the clutch plate doesn't smoothly slide on the tranny input shaft, leaving it lightly engaged and thereby inducing a bit of drag on the gears which interferes with smooth sliding of the engagement dogs).

With the transmission on the bench the output shaft does not turn as smooth as I expected it would, BUT it shifts up and down like it should.

The normal shifting on the bench is another sign pointing in the direction of dry splines rather than shift mechanism damage.

As to the smooth turning, you may feel "bumps" as gear teeth engage one another, but there should be no "gritty" feel. FWIW, if it were my tranny, I'd pull it and have someone with experience and a track record of doing airhead tranny work "right" (e.g., Tom Cutter, Anton, Oak) open it up and inspect the bearings and install the circlip if needed, before putting any significant additional miles on the machine. The problem is without the circlip, the axial thrust loads push the adjacent gear against the inner bearing race on the end of the shaft, applying an axial load the bearing was not designed to handle. Bearing failure and then consequent damage from debris in the oil and the output shaft "wobbling" ensue not long after.

[edwarddieck]

No oil for that drive shaft.

Non, hope for a quick fix! Make sure the vent hole in the bolt holding the speedo cable in is open. Run some wire thru to open it. Ride and HOPE it is OK. If not then get ready for some work.

If it is tranny oil then you have a seal leaking. Usually caused by the shaft moving because of no circlip. Look here, www.largiader.com, lots of info and photos. He rebuilt mine on my '94 R100R. Lots of other Airhead shops know what to do.

Good luck,
Ed

[R100RT_Mark]

Regardless from where the oil is coming, it really should not be dirty. Dirty suggests something undesirable is going on. Might be lack of maintenance, as simple as having an over filled transmission/final drive, blocked vents, or a failure/pending failure of a component or system

Some other info would be helpful. Such as, use history – hard and daily vs. light and infrequent, how many miles; when was its last comprehensive oil service – i.e. engine, gearbox, final drive; what was the condition of, and what debris was in, the respective oils, etc. Then there’s perhaps the two most important pieces of information, what is your intended use/duty cycle requirements, and what kind of budget do you have with which to work?

As far as the splines go, it is a characteristic of moly-type lubes that means “our” splines are going to look dry within a heartbeat of being serviced. The carrier grease soon dries/gets dispersed, leaving behind the moly. Think of moly as a microscopic dust that permeates the metal surface. As you have the transmission off the bike, I suggest you focus in getting all the related parts clean of any oxidation and debris before reassembling.

I have experience with two transmissions that have been “circliped”. The one Anton rebuilt for my 30,000 miles or 1994 R100RT is much sweeter than the one I inherited on my 1993 R100R which had had the work done by a local shop just a few miles before I bought the bike.

Bad changing (up, down, or both) can simply be the result of a poorly adjusted mechanism (there’s one very simple right way to do this, but many simple wrong ones), or a worn clutch cable.

I think you may have jumped too quickly to the “I need a $600 plus transmission rebuild solution”. Knowing very little about your circumstances or the bike’s history, but seeing that you are comfortable whipping-off the transmission, I would be tempted to suggest that you clean everything, and carefully lube/reassemble/adjust everything (maybe replace the clutch cable), ride some more and see if the problem persists. If it does, play at being a scientific detective.

[sarelp]

As far as the history of the bike I dont know, I bought it from a dealer and it have ??70000 miles on it. I took it for a test drive before I bought it and it shifted fine. I checked the oil in the tranny and final drive and it looks really clean.
I bought it for my 15 year old son so he have something to ride on to the rally. Lately I noticed the shifting problem, down from 3rd to 2nd and 2nd to 1st. But if you pull the clutch a second time it shifts right into gear.
I just wanted to fix the oil leak and lube the splines since I dont have any history on it.
As far as the oil in the drive shaft housing being dirty it is probably because its been in there for a long time
I intend to use it for a daily rider but I need it to be dependable for long trips as well. I think for right now I'm going to replace the rear output seal on the tranny( if I can get the yoke off) and then lube the splines and put it back together.And test drive it to see what happens. Can I reuse the 4 bolts on the driveline yoke if I apply blue loctite?
Who is Anton and can you tell me more about the circlip issue, when does it become a problem (mileage wise) or is there no good way to tell., and what are the signs when things are going wrong.

Thats what she looks like.

[brittrunyon]

BEAUTY!

[R100RT_Mark]

Agreed. Very pretty bike.

.... Lately I noticed the shifting problem, down from 3rd to 2nd and 2nd to 1st. But if you pull the clutch a second time it shifts right into gear....

Unless the clutch cable is known to be good, replace it. Worse case is that the current one is good enough and you end up with a decent working spare. Best case is that it might solve all your shifting problems. Do not lube the cable. All BMW cables from the late 1970s have a self-lubricating inner liner. Common oils make the liner distort/expand and the cable becomes junk.

….I intend to use it for a daily rider but I need it to be dependable for long trips as well. I think for right now I'm going to replace the rear output seal on the tranny (if I can get the yoke off) and then lube the splines and put it back together. And test drive it to see what happens….

Seems like a good plan. Increasing trip distance gradually over time builds experience, knowledge and confidence.

….Can I reuse the 4 bolts on the driveline yoke if I apply blue loctite?….

Depends upon to whom who listen and then if you trust their judgment. I do not see much advantage to trying to save the $10.00 it costs for four new screws.

….Who is Anton and can you tell me more about the circlip issue, when does it become a problem (mileage wise) or is there no good way to tell., and what are the signs when things are going wrong….

Anton is Anton Largiander http://www.largiader.com/. A regular forum contributor and an airhead “guru” who is respected for his expertise and pragmatic experienced-backed advice. His web article on the circlip issue is here http://www.largiader.com/articles/circlip/.

I do not think that there is a known “mileage” point where the circlip issue raises its ugly head. One of my bikes needed attention after 16,000 miles (done just before I acquired the bike). The other after 30,000 or so and manifested itself with a very clear low frequency vibration through the transmission – as if I were constantly running over an open mesh bridge grating. The latter over the last 50 miles of a 350 mile week end trip.

[20774]

Another decent article on the circlip:

http://www.gunsmoke.com/motorcycling...lip/index.html

[GRAHAMM]

shifting issues from 3rd to 2nd to 1st was an issue for me especially if trying to do so at stop, going through the gears in motion... no problem.

lubed the input shaft of tranny with Honda Moly 60 and now its' nice and smooth and able to shift to 1st at a standstill.

For tranny issues watch your drain plug at oil changes for metal filings.

[sarelp]

Thanks everyone, if I can get the yoke off I'd be in good shape!!

[42906]

Very nice bike. The Mystic was the best of the old airhead twins. BMW finally figured the handling out and gave it enough trail to eliminate all the weird wobbles and weaves of earlier generation twins.