This exploded parts diagram shows how the clutch actuation works. The lever #14 is attached to the clutch cable and handle bar lever which pushes on part #1 to release and engage the clutch. When I pulled mine apart to see just how bad the needle cage bearing #4 was on mine which I guessed had failed this is what I found below.
There was no bearing at all!! All I found was a silvery crumbly paste and the three small bits of roller bearings to the right. The bearing was completely ground down to dust! That might explain a few things!
The push rod (#1) goes through the center of the splined input shaft to the transmission. An unusual but compact design. The end of mine looked like this, very heavily worn and mushroomed out making it impossible to pull out through the back. Normally you do not need to pull the transmission out to inspect all these pieces and this regular maintenence of inspecting and lubricating the needle cage bearing can be done with everything still on the bike. (I wish I had known that ahead of time and perhaps my bike wouldnt have broken down in the first place) However, as this part on mine is completely mangled the whole transmission would have needed to come out anyway.
Why doesn’t he just pull it out through the front of the transmission you might ask? This is why. On the other end the shaft is fused to the washer and it’s impossible to remove! This is looking bad for what other damage I might find… Time to get out the hack saw or dremel cut off wheel.
I was not expecting these pieces to be so mangled, so I need to pull apart the clutch and check for additional damage and see what other parts I need to order.
First step in pulling apart the clutch is to remove every other bolt. These parts are under tremendous pressure and if the pressure is not released slowly and evenly you could loose an eye or more importantly damage the flywheel. The existing bolts are not long enough to fully release the spring and longer ones need to be put in.
I used these bolts, available from Jeff Trapp at Northwoods Airheads. Screw them in a ways and then finger tighten the nuts down to the surface of the plate. Then you can remove the remaining stock bolts.
Then just unscrew the nuts evenly to back the pressure off. You may need to use 2 wrenches if the bolt starts spinning with it, I did on one of them.
Clutch parts look in remarkably good shape. Previous owner had said that the best parts were pulled from an R75 with 35K ish miles and quite a few miles put on since then. They still look good.
Still a lot of life left on this friction disk, wish I had known it looked this good before I ordered a new one a week before I started this. I’ll keep it for a spare.
Unfortunately it looks like the pressure plate needs replacing, the center is just mangled from the frozen push rod. It may be salvageable but I’m planning on keeping this bike for a long time and put a lot more miles on it, better to replace it for piece of mind. I had not expected this piece to be damaged and had not pre-ordered this before starting, now I have a long wait ahead of me for a new one to be shipped.
The back side of the pressure plate is a very thin spring like plate, its almost like a pie plate. I have no idea what function this serves. Anyone know?
Parts I had pre ordered quickly arrived in a few days, this is my new spring and new-fangled Siebenrock “Super Clutch” friction plate. Supposedly this newly designed plate is oil proof and will keep working if you get a rear main seal leaking to contaminate the clutch, otherwise you’d be dead in the water. They say you just need to keep the engine topped up with oil and keep riding till you can get the seal fixed. They market these clutch plates for the world traveler. If its good enough to reliably make it through Africa and Siberia then it should be good enough to make it to Alaska on my bike I’ll do a review on it in the coming months when the bike is back on the road again.