Problems with the clutch

Hi All.
I have some problems with clutch system.
With the clutch mounted (without steel plates, friction plates, clutch pressure plate and springs) the clutch center turns free, the clutch chainwheel turns free with engine, the gearbox transmission shifts well, the kickstart works well.
No shim between clutch baccplate and gearbox mainshaft/inner cover.
With the complete clutch mounted, the clutch dont pulls whit the lever and the kickstart has been blocked.
I have used five steel plain plates, five new two side friction plates, one side final friction plate.
Maybe the new two side friction plates are too tick?
The last one side friction plate is out of the chainwheel edge.
All the parts, except the new friction plates, come from a running P11.
I need your help to understand what is wrong.
Thank ou.
Piero

Piero

Last friction plate should not be outside edge of chainwheel. This plate must also be on the clutch center splines, or it does nothing to transmit torque.

The last plate outside the chainwheel would suggest the clutch stack is too thick. This could be due to plates too thick or too many plates. The Atlas clutch, for comparison, has only 4 double sided plates and 4 plain plates.

Slick

texasSlick said:

Piero

The last plate outside the chainwheel would suggest the clutch stack is too thick.

Slick

Click to expand...

Hi Slick thank you.
Please, what is the "clutch stack"?.
Piero

Clutch stack is assembly of all friction plus plain plates. The height of the stack should not be greater than depth of clutch chainwheel.

Slick

Hi Slick,
I understand, thank you.
Now the clutch works vey well.
I remove the new "nos" five friction plates with the old but usable.
Now the last one side friction plate is into the edge of the chain wheel.
But remains a question.
Maybe was better to use four of the new plates?
Thank you.
Piero

pierodn said:

Hi Slick,
I understand, thank you.
Now the clutch works vey well.
I remove the new "nos" five friction plates with the old but usable.
Now the last one side friction plate is into the edge of the chain wheel.
But remains a question.
Maybe was better to use four of the new plates?
Thank you.
Piero

Click to expand...

Piero

I am not expert in difference with Atlas four friction plate clutch and P11 five friction plate clutch. If clutch chainwheel is same for both Atlas and P11, then five friction plate clutch must use thinner friction and plain plates. Be careful not to mix plates from both type clutches.

Slick

Hi Piero,
The clutch baskets (sprockets) for all 750 Nortons from 1966-1968 are listed as 040359 however, there were two types made over the years of different depth. See RGM link.

http://www.rgmnorton.co.uk/shop/search. ... rch=Search

Also, the parts book lists different part #'s for the P11 and Atlas double sided friction discs: 043192 and 043442.

The plain steel plates have the same part #: 043191.

So I can think of a couple of possibilities.

1) You have the shallow clutch sprocket or

2) The P11 double sided discs are thinner than Atlas type and you have the Atlas type.

Ed

Hi Piero

APRRSV has good information.

I was looking at an exploded parts diagram for the Atlas which shows four friction plates, but the Atlas parts quantity calls for 5 friction plates. This exploded diagram thus caused me confusion. The four friction plate clutch is for the earlier Model 99.

I agree with APRRSV that you have a mismatch between the clutch chainwheel and the friction plates.

Slick

Hi All and thank you.
The clutch works great now with the original five friction plate.
The new one was thicker.
The stack with stock plates are smaller of 3/4 mm and is in the edge pf chainwheel.
All the clutch parts are P11 original.
Piero