TOPIC: Drive Train-Slimline-clutch

"(2) 1/2 bare/1/2 friction plates" 043193
Wondered about this second bare/friction plate.

A few measurements explained it's possible need....
With only one installed behind the aluminum pressure plate and after only ,061" of cumulative wear of the friction surfaces the spring cups WILL bottom out in the clutch center pockets. This would cause the clutch to no longer have squeeze on the clutch stack and start to slip.
The second split function plate would increase the bottoming out dimension to .178" of stack wear.

Leaving out the second plate and instead using an early thick alumnum pressure plate could do the sane thing...
I will look further into this and see if it is practical. I'll report back here.

Hi Dave so thanks for your help as always so I use this site to see what members think of clutch woes on my Atlas
Dave has been great on advice on diagnosing what could be wrong with my clutch basically it wont release enough so have clutch drag and yes have done all clutch adjustments as shown on websites and manuals clutch internals are all in good condition and same for clutch lever (7/8 ) and cable. Did clean friction plates so at moment running dry
Also received advice from Mike Friel and have checked his list all good so far.For those of you that have an atlas or similar
Motor how far to the pressure plates actually release when lever is pulled in all the way
Thanks Bruce

I am working on Ron's manxman in pix. I will be able to operate it and make pull measurements soon.
I noted Phil mentioning the wear status of the main shaft bearing preventing clean disengagement , though the clutch assembly(and shaft) would both visibly move...therefore potentially still drag.

ADDED:
Ron's clutch center was evidently rebuilt in some time past, by mickey mouse? Even after a very thorough kerosene bath defunking, The roller cage refused to revolve on the race unless forced by pushing on the cage. This could also be a clutch drag causation...

I then have 3 late and one early FB clutches and proceeded to kerosene wash them for comparison. The roller cages all revolved easily by gently rotating the clutch basket.

I'm guessing a dragging poorly sized aftermarket roller cage or flipped over installed inside out?

Hi Dave here are photos of my clutch assembly thanks Bruce

Are your 4 steel clutch plates fine paper jitterbug sanded both sides smooth as a baby ass? (never ever sand blast) and you should have one more plate if it will fit.
Look very rough red from rust? Are the vertical slot faces of the clutch center clean, rust free, and smooth where the friction plates slide.ride? same for chain wheel-clutch basket, which is also a clutch plate ?
wash with atf or kerosene before assembly wet assy is OK

Book says 5 plain 5 friction 1half friction
Rons was short 1 clutch and 1 friction
correct pieces I added fit OK

Added:
Are there any swollen "bumps" on any friction plate "friction pads". These high spots can also cause drag
I've seen some on a few of my old used stock.

From NOC:
Hello again Bruce - It's as I feared. You;ve got after market SS friction plates or Dominator friction plates which are thicker than the SS ones. So there isn't room for the missing steel plate. RGM sell an extended chain wheel for such eventualities. Good luck, Howard


What is he afraid of?
Friction currently has 12 interfaces on Bruce's clutch is where any drag originates. The ability of those interfaces to move/clear each other is controlling to "free up or drag".
Basket is a driven clutch plate along with the other clutch plates which must also move to "free up" from the clutch center plus the other friction plates.or you have drag.
I agree that undersized rollers would possibly cause additional microscopic movement and reduced support, cyclic tipping, of the basket at each rotation. This cyclic tipping could cause friction by touching.
I don't see the thickness of the plates particularly contributing to extra drag, the number of interfaces remain the same unless the number of plates changes.