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1984 r100rs Trans leak

ckp543

New member
I have A 1984 R100RS I noticed fluid seeping out of the rubber boot where the clutch lever is has anyone ever come across this?
 
What about any past servicing? Any chance you overfilled it? A little tough to do, though, provided you're filling through the plug on the side of the tranny...once it the fluid begins to run out of the plug, you're done.

What about the speedo cable bolt? It has a hole through the middle which is designed to allow the build up of pressure due to heating of the oil to equalize. If the hole is plugged, overpressure could do bad things, forcing fluid out places it shouldn't go.

It could be that the rubber ring around the thrust piston has torn...item #6 on this diagram:

http://www.realoem.com/bmw/showparts.do?model=0333&mospid=51642&btnr=21_0069&hg=21&fg=51
 
I have the non adj pivot arm design my inard look different I'm gooin to change the fluid this week but Am going to look into the bolt you said thanks for the info!
 
Your boot may be torn or cracked. The boot on my 81 has a little oil in it when I remove occasionally. The gear oil level in the tranny is approx. 2 1/2" lower then the push rod so it cant drain out.
I would look for a damaged boot and replace it or tighten the clamp a bit. Here are your components. Item 15 is the seal and would be a PITA to change.
84clutch.jpg
 
I have the non adj pivot arm design my inard look different I'm gooin to change the fluid this week but Am going to look into the bolt you said thanks for the info!

non adjustable arm ? I did not know your modedl came with a non adjustable. live and learn
 
Your boot clamp is loose or the boot is torn for oil to be coming from there. There is no seal to change a oil splash is how the through out bear is lube.

Don
 

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I pointed out the wrong part for the seal. The push rod seal is in the back end of the input shaft. Item 16
inputshaft.png
 
I pointed out the wrong part for the seal. The push rod seal is in the back end of the input shaft. Item 16
inputshaft.png

His bike is a 1984 the seal you point out is not use on this bike. They change after 9/80 on this. Only the boot keeps oil from coming out.
 
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His bike is a 1984 the seal you point out is not use on this bike. They change after 9/80 on this. Only the boot keeps oil from coming out.

Take a minute to look it up DON. He has the same assembly that I have on my 81 R100RT. The drawing is from 81 on and his is an 84....correct?
 
I looked at the parts book and I don't go along with that. I know I replace that seal when I had to rebuild my transmission on my 75 R90. The push rod and through our not the same as my 82 R65. I just had the transmisson out on the R65 to lube the splines there is no seal where the push rod goes on this and never has been. The transmission on my R65 has never been apart and I have had this bike since new and have close to 100,000 miles on this bike.

Don
 
I looked at the parts book and I don't go along with that. I know I replace that seal when I had to rebuild my transmission on my 75 R90. The push rod and through our not the same as my 82 R65. I just had the transmisson out on the R65 to lube the splines there is no seal where the push rod goes on this and never has been. The transmission on my R65 has never been apart and I have had this bike since new and have close to 100,000 miles on this bike.

Don

Here is the seal you claim doesnt exist and it goes in all the 81 thru 95 airhead gearboxes. Including yours. It's the red insert tapped into the end of the shaft to keep any oil from migrating forward onto the clutch plate. You can see the trough at 5 o'clock to allow oil flow to the throw out piston and bearing.
pushrodseal.jpg
 
Well I found the clamp just spinning around boot has no holes tightened clamp rode about 7 miles no leak yet? Hopefully in the clear!
 
I have the same (or similar) leak in my 78 R60/7. Here's what I attempted as a temporary fix:

1) loosened clamps and rotated boot so that crack/hole was on top (maybe could have stopped here?)

2) cut a piece of bicycle inner tube and clamped it over the hole (also considered patching with some type of rubber sealant, but didn't want it dripping inside the hole. any ideas on this?)

so now i'm wondering a) is that gear oil or engine oil in there, b) is it a problem that there's oil inside that boot, and c) did i create another problem by removing the easiest exit for wayward oil?

ps: yes i know i need a swingarm dustcap; working on it.
 

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Some techniques I have used which worked in the past for patching such a rubber boot are:

1. Get some GOOP (amazing goop, a thinned shoe goo); uses a toluene solvent:
Generally a good repair - Goop is applied like contact cement to the boot and repair rubber but takes 48 hours to fully cure. Cement is a rubber compound.

2. Barge's cement - contact cement; uses a toluene solvent :
Good fix, quick repair, fully cures in 24 hours but is useable in 1/2 hr. Apply as a contact cement to boot and repair rubber, remove pieces and let dry for 14-15 min. then apply patch. Good ventilation is required (I try to use gloves). Note: I don't recommend trying this with the newer non-toluene version of Barge cement (YMMV). Cement is neoprene rubber.

3. Rubber cement - same stuff used if you ever patched a tire inner tube; usually hexane solvent:
Fix depends on type of rubber. Apply as a contact cement on boot and rubber. Let dry ~10 min and apply. Fully cured in 24 hours. Cement is a latex type rubber.

In all cases, dry, oil free, slightly scuffed rubber surfaces help. The Goop is the thickest of the choices , but may be easier to find. A thin layer of adhesive on the boot and patch are best. Good luck!
 
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