Clutch pong

mspenz

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Complete new clutch kit and slave just fitted to my 1150gsa but I'm getting a hot rubber smell when I first move and only when cold :confused:
There was a bit of new clutch smell when hot for the first 100 miles say but that has totally disappeared now and I have the rubber pong, happens when I start the bike then move a few metres onto the drive through a narrow gate (little bit of clutch slip required I suppose), I stop to shut the gate behind me and that's when I smell it...only at the initial move and when cold!
There's no clutch slip.

Fluids don't appear to be going down and it's not the alternator belt, this is 300mls in now and I have a Balkans trip coming up soon so would rather deal with it now if I have to or is it just a bedding in process and nothing to be concerned about :nenau

Mike.
 
Swivel down the final drive and check the rubber driveshaft sleeve isn't melting or starting to slip. It may look like the rubber bonding is melting or you may find rubber granules in the swingarm.
 
Swivel down the final drive and check the rubber driveshaft sleeve isn't melting or starting to slip. It may look like the rubber bonding is melting or you may find rubber granules in the swingarm.

Ok, I'll have a look. Wouldn't it do it all the time though if the bonding is knackered and also get worse under load? I was out for a run today with my partner on the back and the only time there was smell was when I initially moved the bike in 1st gear as described, when I come back I obviously reverse the process to get into the garden and there's absolutely no smell once the bike is hot :confused:
 
I'm not saying it is your problem but you won't be able to say for sure it isn't until you check it. Simple rule of diagnosis, rule out one thing at a time starting with easiest :D
 
Twitchy.

I'm not saying it is your problem but you won't be able to say for sure it isn't until you check it. Simple rule of diagnosis, rule out one thing at a time starting with easiest :D


Yeah, I know. Just starting to get a bit twitchy now as I only have a couple of weeks to get everything sorted before heading off and other things seem to keep stealing my spare time :(

Cheers.
 
Well, the smell disappeared after a couple of days and it was definitely coming from the clutch area. I pulled back the slave cylinder to make sure that there was no gear oil leaking and it's all nice and dry there, pulled the starter and there's no sign of any oil anywhere but I think I know what was wrong now.
I put some of that expensive Castrol spline lube on the gearbox input shaft splines (only about a pea sized amount on a toothbrush) and worked it into the splines, forgetting that the clutch friction plate hub is so short I covered the full length of the shaft rather than just lubing the short area that the plate sits on. This left about 10mm of exposed spline coated with lube which was then thrown off onto the casings on the gearbox side of the clutch..not a problem!
When I took out the starter and looked in with a torch I could see little traces of the lube on the friction plate hub which had been blown backwards (in line with the splines...pretty windy in there I'd imagine) towards and probably onto the plate which would then be thrown outwards onto the fibre and probably causing a slight lack of friction when cold.
It looks to be only particles but obviously enough to have caused the burning smell but it seems to have settled down now and there's no slipping...note to self - only lube the parts in contact :blast

I'll be taking it apart again later to have the input shaft replaced (bit of spline wear and not enough time to have the gearbox done before a trip) so will have to replace the friction plate then anyway so hey ho..I learn :rolleyes:
 


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