Clutch plate advice please...

Have a 71 LR Fastback & '57 Wideline triton in the garage & trying to sort out whether to stay stock or go belt drive. Loads of issues with belts being run in oil so I'm leaning towards stock with better plates.

Now to the questions...

I've been chewing stuff over with a couple of friends over here in the UK & trying to figure why Barnett Commando clutch friction plates come with instructions to soak in oil before use?

Many decades ago a friend did a few very simple basic clutch torque calculations for me demonstrating that Norton clutches must be run dry if they were not to suffer slip problems when lots of torque was applied to them.

Have Barnett assumed, like so many in the past and probably many will do in the future, that because Norton in the 1930s adopted the compromise (a description given in the book Speed and How to Obtain It) idea of shoving the clutch within an oil bath chain case that the clutch was designed to be employed with oil on the friction interfaces and employed a carbon paper friction material intended to be employed with oil??

Does anyone have a data sheet for the friction material used by Barnett showing that the material is also suitable for dry use?

Interesting that BSA Gold Stars employed Ferodo MZ41 friction material and its data sheet states it is unsuitable for use with oil... (I wonder how many Gold Star owners realise their clutches were designed to be run dry)?

Many thanks...

There are a couple of nice advantages running a dry belt primary

the primary will no longer LEAK

the clutch cannot get fouled and slip because primary chain lubing oil found its way into the clutch basket

the entire primary is lighter than a chain one, hence easier on the shafts and bearing

as far as lightly oiling the barnett friction plates, do it, I did not some years ago and they quickly wore off the friction material and had to throw them away

just rub a little light oil or ATF in the friction pads

looks like BDM/leadbeater has reappeared from this

Moosevan said:

Many decades ago a friend did a few very simple basic clutch torque calculations for me demonstrating that Norton clutches must be run dry if they were not to suffer slip problems when lots of torque was applied to them.

Have Barnett assumed, like so many in the past and probably many will do in the future, that because Norton in the 1930s adopted the compromise (a description given in the book Speed and How to Obtain It) idea of shoving the clutch within an oil bath chain case that the clutch was designed to be employed with oil on the friction interfaces and employed a carbon paper friction material intended to be employed with oil??

Does anyone have a data sheet for the friction material used by Barnett showing that the material is also suitable for dry use?

Interesting that BSA Gold Stars employed Ferodo MZ41 friction material and its data sheet states it is unsuitable for use with oil... (I wonder how many Gold Star owners realise their clutches were designed to be run dry)?

Many thanks...

Click to expand...

I have found there was no way oil can be prevented from fouling the clutch plates. I have filled the primary with oil until it just touched the lower chain run ..... still got oil on plates.

So, I suppose Barnett designed their plates to inevitably run in oil.

BTW ... I assembled my Atlas clutch dry with Barnett plates, and let the bike sit for several months while I attended to other things. When I tried to free up the clutch before starting, there was NO Way! Some other poster on this Forum found the same thing...... plain and friction plates were stuck together. Reassembling with oil smeared on plates solved the sticking problem.

So, follow Barnett's instructions and pre oil plates.

Slick