As far as I know, all of the Beemers will eventually need to have the transmission input splines [commonly (and arguably incorrectly) referred to as the clutch splines] lubricated during service. The big question is how often, and how much of a bear of a job it is to do it. I decided to try it out on my cafe'd R80RT because I've had the bike for over a year and a half, I haven't done it, and it's humid here in the southeast. Whatever reason works, but it had to be done. Total time spent on this go around was about 3.5 hours, but that included a lot of cleaning and "while you are there" maintenance. I did not service the throwout bearing, but I did shoot fresh grease into the swing arm bearings.

Here's our victim: my 1983 R80RT with just over 50kmi on the clock - just a baby in the airhead Beemer world. I have removed the side bags, opened the seat, and removed the tool box. I also remembered I didn't have a camera, and I also have a much neglected website that needs some kinda update...

Here are the knurled knobs for removing the fuel tank. They are located just under the rear of the tank.

Set both fuel petcocks to "Zu/Off". I actually started the bike and ran it a bit, just to use up some of the gasoline in the fuel line that I'm about to disconnect.

Told ya. Disconnected fuel lines. Now carefully lift from the rear, then pull backwards...

...and it should come right out. Now we're gonna dig into the air filter housing a little bit.

Flip the 4 hold down tabs for the cover and remove it.

Next I disconnected the intake pipes and the pulse air injection lines.

I completely removed the intake pipes from the air filter housing and the carburetors, but I was able to negotiate around the pulse air injection lines. Long term project: put that system to rest. It just gets in the way.

Looking down into the air filter housing. You can see the central bolt there, but the upper transmission to engine fasteners are hidden. We'll need to remove some stuff first.

I pulled the metal insert out of the intake tubes, then removed the tubes from the air filter housing. There are circular spring clips for the crankcase breather system, so don't just yank things apart - be careful.

The pulse air system bits are just held in with those 24mm nuts. I removed the nuts and the aluminum seal rings, then reattached them so they wouldn't get lost. There's a small vacuum line that also needs to be disconnected, so again - don't yank things apart.

Here you can see that the central bolt has been loosened, and the upper left fastener has been removed. The upper right fastener, however, is a stud. That means I'm going to have to do some additional disassembly so I can remove the air filter housing.

Additional note: that central bolt needs to go back in with a bit of thread sealer. No, not thread locker - put the Loctite down now!

Out with the battery, and disconnect the 4 nuts holding in the battery box. Just lift it up slightly so you can have clearance to remove the air box.

Boom. Airbox removed.

Now onto clutch bits. Here's the cable (filthy, I know - I cleaned it later).

Cable disconnected.

While I was on that side of the bike, it was prime time to disconnect the rear brake. Otherwise, it's going to bind things up when I go to slide the transmission and swing arm assembly backwards.

110 half turns. I counted. I'm OCD enough to count something like that.

Back to the clutch arm. Again, I did not remove the arm and service the throwout bearing on this trip.

10mm pivot bolt removed, and now the clutch arm is free on both ends.

I popped the covers for the swing arm bearings and used my generic special tool to crack the lock nuts loose. The generic special tool needed is a 27mm socket that has been faced (the opening has been cut down to remove the bevel, because the nut is thin) and turned down on a lathe (because the opening there is not wide enough for a full-sized socket to fit). First time using it, after purchasing it probably a year ago. Worked like a champ.

I was moving too fast. Need to disconnect either the shift rod, or the shifter assembly. I chose the former.

Here I have my floor jack in position on the frame, and I'm backing out the swing arm bolts.

And here they are, in all their petrified grease glory.

Additional note: when you go to put these back in, you'll need to pay special attention to centering the swing arm. Torque to 15lb/ft, then backoff and re-torque to 7.5lb/ft. When you're happy that things are pretty close to being centered, tighten the locknut to 75lb/ft. Then recheck to make sure nothing moved when you put some oomph on that locknut.

As you can see, the swing arm has shifted out of position. If you look at the high-res photo, you'll see that the bearings installed are the 30203A sealed type.

Now for the bottom fasteners on the transmission.

One on the left, and note the ground wire.

And one on the right above the clutch cable boss.

This guy has a nut on the back, so don't be fooled by just turning and turning the hexhead bolt.

And with a light tug backwards and a little finagling, here's what we've been looking for: the input shaft splines. Clean out the splines with a brush and a fast-evaporating solvent, and be careful not to get any of the mess on the clutch disc. I covered the disc as best as possible with clean rags before thoroughly cleaning the splines. After everything is clean, lightly lubricate the splines with a high-molybdenum disulfide grease - the Airhead community believes in Honda Moly 60 paste, so that's what I used.

As any Haynes manual would say at this point, reassembly is the reverse of disassembly. If the splines give you grief matching up with the clutch disc, rotate the rear wheel a bit - you did put the bike in gear before starting all this, didn't you?!?