Comet Gearbox

bodlan

Well Known and Active Forum User
VOC Member
Well now. I've just taken the Burman outer cover off in order to check the clutch lifting bits.
I have the long rod in mine and there should be a ball behind the forked actuating lever apparently, but not in mine! This would explain I suppose why my clutch has never been that light in operation since I've had it. KTB recommends splitting the push rod in two and adding a 1/4 roller in the middle and a 5/16 one behind the short clevis actuator.
Has this modification proved successful for all you other Comet owners?

Cheers
 

Comet Rider

Well Known and Active Forum User
VOC Member
Hi Bodlan,
On my setup (admittedly with a Conways Honda clutch) I have the following going from clutch arm to pressure plate;

Forked 5/16 push rod
Stellited 1/4 push rod
1/4 x 1/4 roller
Stellited 1/4 push rod
Axial needle roller pressureplate pusher

HTH
Neil
 

bodlan

Well Known and Active Forum User
VOC Member
Neil
Who makes the axial needle roller pusher? Is it a standard 'SKF' or similar catalogue item?
Did you get some local engineering firm to do the stellite tips on the push rods?
 

davidd

Well Known and Active Forum User
VOC Member
Neil
Who makes the axial needle roller pusher? Is it a standard 'SKF' or similar catalogue item?
Did you get some local engineering firm to do the stellite tips on the push rods?

The cylindrical spacer may be a standard item, but my experience is that it is only available in massive quantities. When I order them from Coventry, John often kids that he only has several thousand left.

I buy rod that I can oil harden, which is easily available. Stellite seems like over-kill. I have always assumed that the object was to isolate the actuator end of the rod from the turning or clutch end of the rod, thus minimizing wear on the lifter mechanism. So far, I have never had any wear issues.

David
 

Comet Rider

Well Known and Active Forum User
VOC Member
Hi Bodlan
1/ Made the needle roller pusher myself. Bearing came through RS components for about £5 if I remember corretly.
I turned up a carrier to hold the axial needle roller with a cup in the back side, then case hardend it with CASENITE
2/ The pushrods were made from Silver Steel rod with dobs of stellite on the end, which were then ground flat.
A fellow member gave me a small pack of the stellite and flux, and when I see him next I'll try to get details

HTH
Neil
 

nkt267

Well Known and Active Forum User
VOC Member
One thing that really helps with good clutch release on a Comet is the operating lever..It should have a raised half round??(not that much really) section that bears on the forked push rod.My theory is that as the arm pivots, the fork 'rides up' the raised section effectively giving a little more lift to the clutch mechanism..(I'm starting to duck already)..John
 

chankly bore

Well Known and Active Forum User
Non-VOC Member
Oil hardening silver steel is all you need. Hitchcock Motor cycles have a Royal Oilfield needle roller clutch lifting "mushroom" that looks interesting. I'm not sure stellite is necessary unless you spend a long time in first gear at traffic lights!
 
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