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Clutch confusion

Posted: Fri Dec 23, 2016 2:16 pm
by Chris Tindal
Having a bit of a senior moment with the clutch (Iron barrel, 4 speed type), it's a couple of years since I did one. Having dismantled it, put in new bearings (54) in the sprocket, new plates, new pad (improved spinning type with bearings), new outer plate, new circlip and single long rod and new springs. I have assembled it the way it came apart, but when I tighten up the three bolts the springs are fully compressed and the clutch and lever are solid. If I slacken the three bolts off so they aren't fully compressing the springs then the clutch works fine. I've been around the block and through traffic and it works ok, but those three bolts aren't tight, but they should be. What could I have done wrong, if I leave then untightened then they will work their way out. There's also a noticable whine, any suggestions?

Clutch confusion

Posted: Fri Dec 23, 2016 3:09 pm
by Mark M
Chris, when I did this to mine I found the clutch release pad (roller bearing) was slightly longer than the plain one and I had to shorten the pushrod accordingly.

REgards, Mark

Clutch confusion

Posted: Fri Dec 23, 2016 3:34 pm
by Gwilly
Couple of things spring to mind, whats this single rod from? should be two part and clutch pad with the inclusion of a 5mm or 1/4" steel ball.

Sounds like the rod is too long if the actuator has been adjusted correctly..

Can you measure or compare the new rod with the old components including the 1/4" ball?

Secondly something wrong in the clutch pack, maybe dished plate wrong way round.

First dish on faces towards you, and last dish on faces inwards, away from you..

Clutch confusion

Posted: Fri Dec 23, 2016 4:41 pm
by Chris Tindal
Its a 1959 bike Gwilly, they originally had a single rod, although it did have the two shorter rods and a ball before so that might go back in. Yes the new clutch pressure pad is a bit longer, I thought screwing back the adjuster on the clutch lever would account for this. I'll take the gearbox cover off and take another look, and maybe shorten the rod or put the two rods and ball back in. Thanks chaps for your input.

Clutch confusion

Posted: Sat Dec 24, 2016 8:05 am
by Dennis C
I am a bit puzzled here surely if it were to do with the rod then the clutch would not work so all the fact that loosening the spring bolts let's it work ok indicates the plates are closing together.

the problem has to be the way it has been assembled or too many plates fitted?.

Clutch confusion

Posted: Sat Dec 24, 2016 8:08 am
by Dennis C
Predictive text, "would not work at all"

Clutch confusion

Posted: Sat Dec 24, 2016 10:06 am
by Chris Tindal
See what you mean Dennis. I think I'll have to take it to bits and start again.

Clutch confusion

Posted: Sat Dec 24, 2016 10:02 pm
by Leon Novello
For the record; if you do go back to the two rod set up, you will find that using a ceramic ball instead of a steel one will stop heat expansion altering the length of the rod, so the adjustment at the handlebar lever will remain fairly constant. Of course this will only appreciated in heavy stop/start traffic in Summer.

Clutch confusion

Posted: Sat Dec 24, 2016 11:40 pm
by Leon Novello
Something to read on Christmas day.
http://www.snowvalley.20m.com/bikes/clutches.htm

Clutch confusion

Posted: Sun Dec 25, 2016 7:17 pm
by Tim NZ
Do you have the correct pressure plate? There are at least three variants to match different push-rod thrust pad ends...