Clutch drag

Timmyboybunter · Post by **Timmyboybunter** » Mon May 09, 2016 12:36 pm

I have an issue with my new to me Thunderace. It is very hard to find neutral and sometimes, having come to a halt in e.g. 1st gear, the bike seems almost to lock.

If I apply a small amount of revs, I can then change up into 2nd and then trial and error doing this a few times usually ends up in neutral.

I also noticed yesterday when moving the bike from cold into the garage that it was very gently creeping forward in 1st gear when I had the clutch lever fully pulled.

Am I correct in thinking this is what is known as 'clutch drag' - and are there any obvious things to look into? I've read that finding neutral can often be tricky on these bikes but I think my issue is a bit more than that. I don't know when the clutch fluid was last changed, so assume that is the quickest/cheapest and most obvious place to start.

No issues when riding along, all gear changes are fine.

Thanks in advance.

Post by **Stig** » Mon May 09, 2016 2:16 pm

It's a known issue but not over common. You're in the right area with the fluid

First check the slave cylinder on the sprocket cover is ok. The seals weep but can be successfully rebuilt without much trouble. Also change the fluid and bleed out all the air. This should sort matters

Btw, also make sure your chain isn't too tight. It'll make selecting neutral difficult if it is

Timmyboybunter · Post by **Timmyboybunter** » Mon May 09, 2016 3:06 pm

Thankyou - I did check the chain which feels fine. That's as far as I can manage without a Haynes manual (hopefully arriving today) so will check the other bits and change the fluid out this week hopefully.

Post by **Stig** » Mon May 09, 2016 3:17 pm

There's a gem yam manual free to d/l in the tech section on the main site

Timmyboybunter · Post by **Timmyboybunter** » Tue May 10, 2016 12:58 am

Ta - both will be useful hopefully.

I checked the bike earlier just while it is standing in the garage and the clutch lever had gone completely spongy - checking the fluid level it was way too low. I had an unopened bottle of Dot 4 sitting on a shelf so have put new fluid in and the lever has returned to normal - couldn't see if it has made any difference to the whole finding neutral thing as it was midnight when finished and the bike is too damn loud

It is odd though. I remember thinking when I picked the bike up that the clutch lever seemed quite firm, to the point of making my hand sore whilst waiting at some traffic lights - which is how it now feels again, so I wonder whether there is a leak there somewhere. Monitoring needed.

krazyneil · Post by **krazyneil** » Tue May 10, 2016 11:49 pm

it would probably benifit from a new set of seals by the sound of it

skyerae · Post by **skyerae** » Wed May 11, 2016 5:52 am

I had the issue of my fluid all disappearing one night as I arrived at College for evening classes. Eventually got it home - pushing an Exup up a big steep hill is not an experience I wish to repeat. I changed the slave cylinder seals with genuine seals from Fowlers as I had replaced the brake line with a HEL one and that sorted the issue. Never any obvious sign of a leak so who the hell knows what happened to the brake fluid that went missing.

Post by **Stig** » Wed May 11, 2016 8:17 am

The slave bolts to the sprocket casing. If there's a leak it'll drip around the front sprocket area any May give the impression the output shaft is weeping

If your chain is well lubed and there's a build up of crud in the sprocket area then the clutch leak is missed as it blends in with the rest of the mess

Timmyboybunter · Post by **Timmyboybunter** » Wed May 11, 2016 1:18 pm

Thanks both. I've bought a seal refurb kit now, as I suppose I was lucky that I lost pressure at the clutch pedal at home rather than out and about so it's not worth waiting to happen again.

I'll check the slave cylinder piston, thanks for the tip - there are plenty of 2nd hand cylinders on eBay so that would be an option.

Timmyboybunter · Post by **Timmyboybunter** » Thu Sep 22, 2016 1:32 pm

Update to this one. My mobile mechanic was round changing a tyre and confirmed the slave seal had gone - swapped it out without issue and the fluid level has been fine since and I haven't lost the firmness of the lever, so all good.

However, I still get clutch drag, it's still impossible to get into neutral without revving the engine, and the gearbox still becomes very difficult to shift (e.g. from 1st to 2nd) if I've been sitting with the clutch pulled at traffic lights etc.

My mechanic suggested putting the clutch lever on its highest span may help a bit, but also said (given it is quite an old bike) it may just be a quirk either of the Thunderace in general or my example - and just to get used to it

Is there anything else obvious I can check or try? I was wondering whether fitting a refurb kit to the master cylinder may be an idea, or changing the clutch (my Haynes manual mentioned something about a part in the clutch - can't remember what - which could lead to clutch drag and difficulty changing gear when worn).

redrocks · Post by **redrocks** » Fri Sep 23, 2016 10:07 pm

Although I have other problems I had the same sort of issue on my FZR1000 exup. I went as far as replacing the clutch plates which didn't make much difference (made the level feel smoother and lighter !!!) but ive now dressed the fingers on the clutch basket which had some noticeable indentations where the clutch plates has been rubbing. I'm not sure if you're supposed to do this but its taken ages to clean up the fingers with emery paper. I guessed the plates were sticking in the grooves they'd worn. Unfortunately with carb problems as well ive not run the bike on the road to see if I can get into neutral easier. I've had real difficulty getting in to neutral for ages despite replacing the master cylinder deals etc. Any thoughts?
Andy