I had the rear drive rebuilt by a friend of mine, Matt Iles, who owns Iles Motorsports and is a long time BMW mechanic. You can read about how he did this work here.
I replaced the swing arm bearings and you can read about how I do that here.
The R80ST has a monoshock rear suspension instead of the traditional dual shock suspension that was on all the other airhead bikes I have worked on. So the swing arm is a bit different. The procedure for installing the swing arm and rear drive on the 1983 R80ST is the same as for the 1983 R100RS.
Here is the link to the documentation and a summary YouTube video.
VIDEO: 1983 BMW R80ST Install Swing Arm, Rear Drive, Monoshock
Here are some before and after pictures.
Original Rear Shock
Original Rear Drive
Original Swing Arm, Rear Drive & Monoshock
Here is the R80ST with the swing arm, rear drive and monoshock installed. It’s starting to look like a real motorcycle again. 🙂
All Done
All Done
nice to meet you
1977R100RS
There is an aluminum gasket on the cylinder base.
why?
Need to rebuild?
can i just use the o-ring?
There is a gap between the cylinder and the block
Kyoutarou,
Starting in 1976, the base gasket was no longer used and a large O-Ring was used to seal the base of the cylinder. It’s possible someone installed the old base gasket by mistake, or was trying to reduce compression on the engine to keep it from pinging.
Here is how I do that work on my 1977 R100RS:
11 BMW 1977 R100RS Install Connecting Rods and Assemble Top End
I hope this helps.
Best.
Brook.
thank you
Cylinder Snugged Up to Engine Block←mine has a gap