Clutch assembly

I am struggling to get the clutch back together now , and wondered if anybody can help? The problem I’m having is getting the intermediate steel plate back on the outer splines of the flywheel. When the clutch is loosely assembled, the steel plate sits out beyond the splines due to the spring length holding it all there. Is this correct? Is it just a case of very carefully lining this plate up as the flange bolts are being tightened up? If so there seems to be a high risk of damaging the teeth if it is slightly wrong as far as I can tell. Also am I correct in assuming that the raised boss in the centre on both friction plates face the rear of the bike? And I thought this would be straightforward. p.s. This is on an 850 1978 twin. Also I know that the friction plates will need centralising.
ReggieV2012-10-17 18:29:56

Use the gearbox cog, take it off and use to align all the clutch plates

guzzibear, I know that the gearbox cog will cetralise the friction plates, but it’s the metal intermediate plate that I am referring to. I can’t see how the cog would centalise this plate? Thanks anyway.
ReggieV2012-10-17 18:33:36


Make very sure you have the starter ring lined up with the dot marked on to the mark on the cases OR your timing marks will be out, I only ever did that ONCE… guzzibear2012-10-17 18:43:16

In the end of the crankshaft you will find there is an M10 thread. Although it is a metric fine thread an ordinary M10 thread will go in for a couple of threads.
I used an M10 long coach bolt from B&Q with a nut threaded on plus 2 penny washers and an old gearbox inlet splined shaft with a 19/32" socket (1/2" square drive) pushed up through the middle to keep the coach bolt central in the splined shaft.
Put the springs on the flywheel then the spring backplate making sure all the springs pop into their respective little pockets.
Now screw the end of the coach bolt into the female thread in the end of the flywheel until it stops after a couple of turns (no need to force it).
Now slowly tighten down the running nut on the coach bolt allowing the end of the dummy splined shaft to push the spring backplate down towards the flywheel thereby compressing the small springs evenly. Once it has bottomed you can very easily thread on the first friction plate, steel intermediate plate and second friction plate onto the old splined shaft. Finally you can place the big plate with the ring-gear on it and tighten down all the screws. You can then release the pressure on the spring plate by undoing the running nut on the coach bolt and take out the alignment tool by unscrewing the coach bolt from the end of the crankshaft.
It takes longer to type this than to do the job! No damaged teeth on the clutch intermediate plate or dishing of it.

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I did a similar thing, I used 3 long bolts with nuts on to get the springs compressed. Then if you look down the small holes in the flywheel you can see the outer splines lining u pwith the grooves, just nudge them round with a small electrical screwdriver till they line up, once in place tighten the bolts down a bit more. Fit the shorter standard bolts and remove the longer ones.

Don-Spada2012-10-18 00:13:37

That’s confused me (not difficult) are the timing marks not on the flywheel and the position of the flywheel bolted to the crank what affects the alignment of the timing markings? I don’t see how the alignmenmt of the starter ring would affect the timing. Are the flywheel and starter ring balanced and marked?

There are pics in all the manuals too much to go into here BUT there IS a mark on cases and a corresponding dot mark on the toothed starter ring …as it is all together you look thro the timing 'ole to check the timing marks do you not???

David and Don thank you for your replys.I think I’m going to get a coach bolt or similar and do it that way. It sounds fool proof to me . Typically, I have measured the clutch plates this morning(I always do things back to front) and they are about 0.5/0.8 mm above minimum specs, so am now considering new clutch plates. Another delay.
ReggieV2012-10-18 13:39:52

Timing marks will be on the flywheel , (usually scribed marks).

+1And if you’re lucky S, D a couple of dots etc.Always worth checking of course. I’ve seen a couple where the marks bore no reasonable relation to the position of the piston All the bestSteve

Apologies it is to do with lining up the clutch n springs
“NB the spring backplate has an index mark which should line up with the TDC mark on the flywheel…alighment of these 2 marksensures the clutch springs willenter the recesses on the backplate” Quote Haynes manual Pg 68/69

There should be a small dab of white paint on the end of the crankshaft and on the flywheel inner rim where the small screws attach it to the end of the crankshaft. These should be matched up so that the timing marks on the flywheel are in correct register with TDC (but I cannot remember if it is TDC on the left or right side cylinder). Never mind!

David wrote; These should be matched up so that the timing marks on the flywheel are in correct register with TDC (but I cannot remember if it is TDC on the left or right side cylinder). It’s TDC on the right hand pot.

All this talk of lining up the flywheel has me worried, can’t remember doing that on mine, maybe I did, it was a while ago.I see the white paint on the flywheel in the pics but not on the plate adjacent

On mine there is a dot on one of the ring teeth and a tiny V on the crankcases about where the bolt between the red wires is in that picture I put some tippex in the ring to remind me to do it. guzzibear2012-10-19 10:32:37

On Don’s picture you can see what looks like the paint dot on the end of the crankshaft at about 10 o’clock position. There should be a matching paint dot just inboard of the six screws securing the flywheel to the crankshaft.
All the best