Transmission / Clutch Seal?

[kbocchicchio]

I have a 1995 R100R Mystic that I bought a few months ago (my first airhead so I am a rookie) with only 1000 miles on it. After cleanup of all issues with 15 year old gas, I when for a ride and found the clutch slipping in 4th and 5th gear. Suspected that the spline lube may have dried out or the clutch control piston was sticking. Decided to lube the spline. I separated the case and cleaned the spline with some carb cleaner. After I blew it dry, I noticed some pieces of an orange in color deteriorated seal of some type ended up in my catch pan (see attached picture). I had not yet disassembled the clutch control assembly other than to remove the clutch arm to allow the transmission to move back. I checked every article and schematic I could find and cannot locate the part or where it came from. Any help would be greatly appreciated.

 

[dennisdarrow]

The seal on the back side of the throw out bearing?........

 

[kbocchicchio]

I thought so too after looking at the clutch control group schematic, but no part number is listed and I can't figure out how it got into the clutch plate area unless I misunderstand where it actuall goes. Any idea of a part number?

 

[CTellman]

Maybe . . . .

Maybe a PO dropped something when doing a spline lube?
Campbell Tellman II

 

[Dave Backmarker]

Clutch seal?

You mentioned the clutch is slipping in 4th and 5th. A slipping clutch will normally start to slip in high gears. The main seal in the transmission is a Viton or similiar material around metal. Have you checked the transmission fluid level? If you added fluid is it leaking?

I was thinking that the debris might be the felt seal that is wrapped around the clutch rod that passes through the center of the transmission but that's close to the rear of the transmission. Are you leaking transmission fluid back to the throw-out bearing?

Sounds like you should pull the transmission and check the clutch disc and springs (still a diaphragm in '95?). If you do this, be sure to use long bolts to slowly release the spring pressure that holds the pressure plate and disc in place.

Let us know a bit more about any other leaking and please describe the slipping more.


DaveM
1975 R90S
2000 R1100RT

 

[kbocchicchio]

Thanks very much for your input. I have completely removed the transmission and inspected all seals. There is no evidence of any oil leaking into the clutch area and no evidence that the clutch area had ever been accessed or the transmission ever removed. All seals look in perfect shape and as expected, the clutch plate looks new. I have checked with several BMW dealers regarding the material I found and talked to a number of techs. No one can identify the seal. They believe that something may have dropped in there during assembly although I find that a bit hard to believe. My clutch control group is the newer style with no felt seal on the control rod. I did find the spline to be dry and the clutch actuation piston measured 1.319". I cleaned and lubed the spline and removed about .005" off the OD of the piston to assure no sticking after the engine gets hot. This is when the slippage originally started to occur. My clutch actuation piston is again the newer style with an integrated shielded thrust bearing and no separate metal shield. At this point I think I am going to put it all back together and see if the slippage issues is solved. I will monitor the transmission oil level (I had just performed all routine maintenance - replaced all fluids, just prior to the clutch issue). Thanks again to everyone for the suggestions and if I discover anythng in the future, I will post it to the forum. Keith

 

[AntonLargiader]

That's a foam donut seal that goes on the shift linkage. The original ones were orange and they come apart pretty easily. The new ones are black. They aren't shown on all of the fiches but I keep a bag of them in stock and put them on everything.

 

[kbocchicchio]

Finally that makes sense. How can I get one? Besides the obvious fuel related problems, I am wondering if non-use for all that time may have had other deterioration issues. After I completely removed the transmission and cleaned and lubed the splines and modified the clutch control pistion to 1.129"(when hot) I rode the bike for about and hour. The clutch felt smooth and was not slipping until I as about 45 minutes into the ride and again it started slipping in 4th and 5th gear. When I had the transmission off I did not measure the clutch lining as I do not have an alignment tool and it looked ok. Besides it only has 1000 mile - how much wear could it have? So here I am with a slipping clutch after it was completely pulled apart and put back together and I am no closer to resolving the issue. Any thoughts would be greatly appreciated.

 

[AntonLargiader]

How can I get one?

Stop by; I'll give you one. Heck, I'll give you two.

So here I am with a slipping clutch after it was completely pulled apart and put back together and I am no closer to resolving the issue.

I'd keep looking at that piston or just replace it with the later one if there is any doubt. If the parts are good, it simply will not slip. The '81-on clutches are just not know for slipping.

If you stopped by I'd probably give you a piston. I have about 10 of them lying around from Oilhead transmissions that I've scrapped. Same part as all of the early R1100 bikes.

 

[kbocchicchio]

Last ride (yesterday) I rode until the transmission got hot and the clutch started to slip. I put it immidiately in the garage and removed the clutch actuation lever, boot and spring. The piston felt loose (and hot too) with a small amount of play and it slid out easily when I grasped the end with some small pliers. I re-measured it hot at 1.129" Anyway, I live near Lancaster PA and don't get to Charlottesville too often. But my nephew just started at V-tech and I might be able to have him stop by. I am happy to pay for the parts but would love to get the seal and a different piston before I replace the entire clutch and diaphram spring. Thanks for your help - Keith

 

[From MARS]

I would take the clutch apart and lightly sand the face of the clutch plate to remove any glazing before going any further. Its not hard to do.

Tom

 

[44006]

Agree with Mars - you really need to take the clutch apart and clean and inspect all pieces. Mystic is too new for me but principal is same I think with older models.

Only 1000 mi on bike stored for long time - why stored and not used - maybe slipping from the start - maybe bad spring temper - maybe wrong initial factory assembly maybe full of mud dauber sand - maybe rust flakes preventing good friction maybe actuating rod bent or ridge cut into it preventing it to back off all the way - I do not think the problem has anything at all to do with the piston but everything to do with the friction material and faces of plates or something preventing proper spring pressure. alignment tool not necessary just careful eyeball for centering

You confirmed the lever on the trans has freeplay (adjust for excess to test)?

 

[kbocchicchio]

Thanks again guys for the input. I intend to take the clutch out and inspect all pieces. I agree with the most likely assesment tha the glutch is glazed. The original owner (who rode the bike for only 1000 miles and then let it sit for 15 years) may have not broken in the clutch properly to begin with and could have done some damage in the limited usage. Age may also be a factor. Either way I will post what I find after disassembly. Keith

 

[jgrooms]

1,000 miles!!!