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I am finishing up a project of mine, a R90G/S. I am having a heck of a time getting the clutch arm installed onto the back of the transmission. This is a 1975 /6 transmission with a /6 block. It has all brand new clutch components, diaphragm, pressure plate, clutch and flywheel. The clutch rod is correct with the groove for the felt ring. It has a all 3 clutch actuating parts IE, bushing, bearing, and piston. For some reason I cannot get the pin to hold the clutch arm on, it feels like the rod is not going far enough in? I used a smaller bolt to hold on the arm, and the clutch actuation works correctly (mind you the bike is not running) I know the only difference between years as far as I remember (pre 81 clutch) is the /5 diaphragm is different and uses the spacers in-between the pressure plate and flywheel. Are the /5 diagrams taller than /6 and /7?
But I cannot get the pin in, I am not going to force it as I do not need a broken transmission cover.
I have installed many clutches over the years and have never run into this problem, any suggestions short of pulling the transmission and inspecting components?
Thanks!!!

Hi dk,

How did you get on with your clutch? I have no bright ideas. Dismantle, check, reassemble. Perhaps your supplier has slipped up and those aren't the right parts? Or a PO has done something tricky, like fitted a non-standard actuating arm?

Its encouraging that you said the clutch will work with a smaller pin. You can't be too far off finding an answer.

cheers
Mal

If the adjuster bolt and jam nut is removed, can you still not align the lever with the two holes in the bosses so that the standard size pin can go in?

I've found it very difficult to install the clutch pushrod from the rear...the felt tends to hang up. I have to get the felt on the rod and push the rod/felt in from the front. Once in, then the thrust piece, bearing, and piston (with o-ring) goes in from the rear. When everything is properly in place, the most aft piece, the piston I think, should be flush with the back of the case. Not the nipple that sticks out, but the main body of the piston. I did my /7 clutch last year and I remember that as being something to shoot for.

Kurt in S.A.

Same thing happened to me, it was the felt hanging up that prevented it from going in all the way. As I understand it, installing it from the front is the correct method.

The rod may be back to front , it has happened before-------

The long rod with the felt is only meant to be installed from the front. Flanders made a special 3 piece rod that could be installed from the rear of the transmission while in place. It had reliability problems.

How can this be so confusing? Just install the rod from the front and be done with it.

Here is how it is so confusing. I had somehow grabbed a k bike clutch pushrod. They are slightly longer than an airhead. Oops. Simple oversight. Yes I know the felt style pushrod goes in from the front. Which i did prior to the transmission being installed. I only pulled it out once from the rear after I couldn't get the clutch arm on. I was worried since there is a slight difference in the /5 diaphragm. This isn't my first clutch rodeo. Just that somehow I mixed up clutch pushrods.

I am glad that you found it. It would be hard for me to make that guess since I am mind reading impaired. Of course in this case your mind wasn't quite on the job either.

In a shop with more than a dozen bikes apart at all times, we had to be very careful with putting the right parts in the right box for use later.

The /5 clutch with those spacers was to allow the clutch dust to escape and still keep the required thickness of the plate. BMW went through a few iterations of those parts over the years. One had to know what the system was and then they went together easily.

Glad it was simple I agree. Everyone had good ideas which I really appreciate. Stupid if me to have parts get mixed up. I am by no means an expert in any particular area so I like suggestions. Thanks for the answer Duane on the /5 spacers.

dkilmer wrote:Glad it was simple I agree. Everyone had good ideas which I really appreciate. Stupid if me to have parts get mixed up. I am by no means an expert in any particular area so I like suggestions. Thanks for the answer Duane on the /5 spacers.

Another sad case of too many beers while doing bike work.