HI i have recently got my 08 beta 125 out from a years rest.

Everythings fine apart from when the bike is hot i lose my clutch and it drags far to much.

I have changed the oil and put in fully sythetic putoline oil. i have adjusted it on the lever as much as i can, and last night i took the clutch apart cleaned the plates and put it back together. But its exactly the same.

Please help!!

thanks Harry

change the hydrolic fluid, moisture can build up, and make it drag, caution...this is not a fun job..

OK I have to ask for a better description.What do you mean "I lose my clutch"? Does it not actuate? Does the lever go all the way to the bar with no resistance? You have to be more specific.

Can you lay the bike over, pull the side cover off and pull the lever to see if the pressure plate is moving? Help us help you.

when the bikes cold the clutch will work fine, the lever will ingage when half way in, although as the bike warms up the lever needs to come closer and closer to the bar untill its on the bar and then drags, ( theres still abit of clutch).

When i got the bike out a few weeks ago i put new hydrolic oil in and bled the bike untiil it was all new hydrolic oil and no air bubbles, at the same time i checked the pressure plate and everything seemed fine their.

Alrighty that's pretty much backwards from what you'd expect but...

If air is trapped in the hydraulics the clutch will be mushy from the start.

If the lever isn't allowing the master cylinder to return all the way past the resevior bleed hole the clutch will slip more as the fluid heats up and pressurizes they system.

If there is a leaky seal or hose the clutch will act as you describe when the clutch lever is held in as fluid pressure bleeds off the clutch actuation point will move and it will drag after being held in for a while.

Since you saw no change with a disassembly of the plates I'm inclined to think the actuation mechanism is leaking. The critical question is does the clutch actuation point change while you're holding in the lever?

Here's what I'm thinking, If the hydraulics are losing pressure it should happen while the lever is pulled in. The system should go back to a fully filled zero pressure state once the lever is returned back to the fully out position. Critical question is are you loosing fluid in the system? Maybe from a bad slave cylinder seal. Usually when the master cylnder seal goes at the handlebar you can see the leak. Also does the lever return all the way? I've seen master cylinders with bad return springs where the lever was set properly but the master cylinder never returned past the resevior bleed hole. The master cylinder piston should come all the way out to seat against the circlip.

Edited December 21, 201213 yr by dan williams

thanks Dan ive had a quick look and i think the seal by the lever needs replacing, seems to be leaking a small amount of oil.

Hopefully that's it. A seal kit is basically the plunger piston with a seal (the seal is already on the piston) and a spring. Remove the circlip, make sure the bore is clean and carefully slip the new piston in being careful not to damage the seal. Replace the circlip and the mechanical is out of the way. Usually the bleeding of the system isn't too bad since it's at the top.

Edited December 24, 201213 yr by dan williams