GSX1100g slipping hydraulic clutch

[gandy666]

hello there,

have a strange issue with the hydraulic clutch on my GSX1100g.

I've had it about 2 months, it was in storage for a year or so. Clutch has been fine up to this point, but have been using the bike in anger for the last 2 weeks, doing about 80 miles a day. had no issues up until friday when there was no pressure on the lever at all. closer inspection revealed that the reservoir was empty and the fluid had turned into a kind of waxy oily stuff.

so i cleared all the oil out of the pipe by blowing through, bled it though, took the slave cyclinder off and cleaned that thoroughly as well, then checked the spring and all seemed well, put it all back together,took the bike to work this morning and all was well.

brought it back tonight and the clutch started to slip after about 35 miles, so was thoroughly warmed up. Plenty of tension still on the lever, I'm thinking that the fluid has warmed up, expanded and is engaging the clutch without me actually putting pressure on it. I changed the oil in the bike about 4 weeks, using synthetic motorbike oil (Motol 5000 10w40) so I dont think the oil is to blame.

I'm thinking it will be fine tomorrow once it cools off, then will start slipping again when it warms up.

I cant find a method of adjusting the clutch as it just engages a lever that activates the clutch mechanism?

has anyone ecountered this kind of thing before?

I was thinking I would open the bleeder nipple when the bike is warm this morning, without pulling the clutch lever to relieve some pressure but the assumption is as soon as I pull on the lever the pressure will go back up and I'll be back to square one.

wondering is the master cycllinder should perhaps have a small valve somewhere that releases pressure in the case of fluid warm up and perhaps that is blocked?

any help appreciated.

cheers!

[gandy666]

would this suggest that if the 'hole'that allows the fluid to flow back in res was blocked it would cause the symptoms I'm seeing?

or if it were blocked I'm thinking the clutch would be engaged constantly cos the pressure was not being released.

only happened for the first time tonight so not sure how its going to be tomorrow.


clutch has been absolutely fine until I put new hydraulic fluid in it then bled it through. assumption is if there were air in the line, pulling the lever would barely engage it.

this appears to be the opposite problem - or perhaps the clutch is slow to release because the push road is sticky with crap.

if i remove the bolts that hold the slave cylinder to the push rod, is the piston likely to pop out? or if i removed the reservoir cap, will that release the pressure so I can take out the push road without having to worry about re bleeding and fluid all over the place? pretty sure the system has been properly bled and there's no air in it

[Pete.]

It does point to a blocked return port. The way to test for it is to crack open a banjo when the clutch is slipping to let out some fluid. If that cures the slipping, the port is blocked.
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[gandy666]

return is not blocked.

drained some fluid out the reservoir and this had no effect.

next cheapest thing is change the oil.

I have 10W40 semi synth in the bike. its a 20 year old shaft drive - the manual says use 10w40 in it but does not specify what type.

any reason why semi synth would cause a slip and if so, what should I be using instead?

[bikenut]

:karma: hi dude,

so an older shafty drive bike ( older?? ) with crap etc in master cylinder, but recouperating ( return ) port clear??

strip, clean etc. all clutch release system.

how many miles and did clutch show signs of slippage before??

may be the eng oil/worn clutch but do the hydraulics first.

if the clutch is like it is how are the brakes?

[bikenut]

see cmnsl for the great exploded views etc.........

[gandy666]

I have a 50ml clutch diaphragm spring holder nut which i need to remove in order to get to the clutch plates.

when I try to turn it, feels like the engine is turning over inside.

have put the bike in first gear (i think the neutral light) is out and put a bar through the back wheel to try and stop the engine moving, but still cant stop it turning.

I have the circlip, pressure plate lifter, thrust washer, bearing, clutch push piece and clutch push rods out, however I cant get any leverage on the nut to get it off, as the whole clutch assembly turns with it.

any ideas?

[gandy666]

i chained the wheel to the swing arm then use and extension bar to give me enough oomph to get it off. was not as much torque there as I thought there would be.


I have the plates out.


there are 10 friction plates and 9 spacers have come out.

does anyone know if the tenth one should come out? i've tried hooking something behind it but appears fast. assumption is only the friction plates need changed.

some of the friction plates are worn. no blue ness on the steels. some of the teeth look a bit worn but still fit pretty snug to the inner teeth 'snag areas on the clutch inner' (for want of a better word).

anyone know how much material should be on the friction plates are we talking a mm, 2mm