Does the forum have one of these threads already? I didn't find it in a search, but my search-fu is weak sometimes. Someone can set me straight if there is one.
At any rate, here is my '93 R100GSPD airhead. The front driveshaft u-joint froze up in one plane, so a replacement was in order. Driveshaft failures were almost unheard of back when BMW driveshafts ran wet, but became common with the advent of the dry Paralever, especially in the GS with its steep swing arm geometry. Anyone who runs CJ jeeps, and newer ones, especially if they are lifted, will be familiar with the issue with front u-joints. This is the second drive shaft to go bad since I bought the bike new in September of 1993. In their infinite wisdom, BMW did not provide a way to grease the Paralever driveshaft u-joints. For a long time, they denied there was a problem, then finally came around and declared driveshafts were a wear item. I have a rant about this, but I will spare everyone.
Now that OEM driveshafts are $750+, I decided to try an Emerald Island greasable and rebuildable shaft. There are people out there that rebuild the OEM shaft (which takes some welding, machining and other dinking around) , but these EI shafts seem to be successful. As you can see in the photo, there are grease zerks. A rebuild kit is available. But I understand the rebuild kits are not big sellers, so the shafts must be holding up. Keeping grease in any of these is the key.
The swingarm, the OEM shaft, and the EI shaft.
Since I am this far in with this degree of disassembly, a clutch spline lube is in order. I've always done this regularly (every 2-3 years), so they are still like new. You can see the splined shaft between the transmission and engine. They can rust if allowed to go dry. The splines are rather fine and will go away if neglected -
Airhead BMW's are great for those who like to get intimate with their motorcycle doing routine maintenance, which a spline lube is. There is nothing comparable on a SOHC4. In comparison, there is virtually no maintenance disassembly on my 750. But it is all fun, and the bike has taken me to some interesting places (and back) so I don't begrudge it a little time.
Valve clearance check and front end service is next, then a trip into the Oregon Cascades is planned.
