Triumphrat

09-08-2005

All I need some help here. My bike is nearly out of guarantee so I am going to start some spannering

.

As it is now summer in UK the rain is a bit warmer and when it gets hot my clutch still gets clunky at low speed & revs

. I have improved it a bit by re-routing the clutch cable & replacing

it but it still clunks

.

I remember some one on this site wrote about rebuilding the clutch & replacing the "bullet". Has anyone still here done that job?
Is it fairly simple?
Do I need special tools?

Jon
:???:

Will · 09-08-2005

As far as I can tell, the problem is not really the "bullet" or "mushroom" so much as it is the way the clutch basket is machined inside. There are some grooves machined into the inside of the clutch basket for some reason, and those cause a certain amount of clunking as the clutch plates pass them. My 2001 made clunking noises, and the 2000 that I have now makes them, too. You will need a really big socket to get pull apart the clutch- I don't know the size since I didn't take my own clutch apart. You will probably also need a pretty substantial wrench to get the nut off with as well, unless you have Popeye style forearms and have been eating plenty of spinach.

I have come to accept it as just one of those harmless quirks that are part of the bike's character, since it doesn't seem to do anything except make a bit of noise.

10-08-2005

I am adding this to this old string now partly coz it fits there and partly coz it may add knowledge for anyone doing a "600 4cyl clutch" topic search.

I have been grumpy about my clutch since day 2. IMHO poor clutch lift or a saggy chain gives ****e gear changes at low speed and that is my S4 's weakest point. I have adjusted the chain & fitted a chain oiler. I have designed & bought a modded clutch cable & re-routed it. But the amount of actual clutch lift and hence the quality of the gear change is still not up to Suzuki, Morini, Yamaha or BSA quality.

In UK we cannot (yet) touch a product if we want to use the guarantee (warantee)!!!!!!!!!!!!!!!!!!!!!!!!!!!
So I have laid off the spannering till now.

today finally pulled off the clutch case & looked at the clutch lifter. It is a bit crude. I have seen worse but no wonder the clutch is poor & the gearchange clunky as a honda!. If they can't design a better linear leverage clutch lift (or copy someone elses') they ought to go hydraulic quickly!

The arm turns a shaft which has a quadrant cut-out. A short pushrod sits on that cut-out part of the shaft. Pull the lever, the shaft rotates and the edge of the cut-out lifts the pushrod. the short push rod is interesting. It is rounded at the clutch end and 1" long so it looks like a "Bullet" as an early poster called it. If it wears; the clutch will engage later - maybe after the lift arm passes the best angle for leverage.

By the way all engineering in UK since about 1970 has been in mm so someone in Hinkley is 'having a larff' the 'bullet' is 25.45mm long = an inch to 3 figures of decimals....

The bullet bears on "mushroom" sitting in a ball race in the clutch centre. Pull the lever, turn the arm & the cut-out, lift the bullet push on the mushroom compress the springs away from holding the plates together.

On my bike when the clutch started to lift the lever was at right angles to the arm. so from that point on, leverage was decreasing and the load was increasingly compressing the cable as against the clutch springs.

If you want to remove slack to reset the angle of the operating lever when the clutch bites, you can put a shim washer between the mushroom and it's bearing. I found a 1mm thick (1/25th of an inch) hydrualic washer which was a perfect fit & static testing looks good, the operating arm angle is now textbook. Test it tomorrow

[ This message was edited by: lcjohnny on 2005-10-09 02:39 ]