2009 125 has all of a sudden developed what seems to be a very heavy/stiff clutch when engaging. Nothing has changed other than a recent change of lever.

There is plenty fluid in the resivoir and the clutch itself is working ok.

Any theories on what might be the issue ?

Does the lever have free play? When the clutch pack gets out of spec (You have to check the finger height) it can become hard. Either the clutch lever was adjusted wrong or it`s time to pull the clutch and bring it back to proper finger height.

Is it the correct lever ?

Why did you change it, did the old one get broken in a fall. Was something else damaged at the same time ?

Lever was bent in a fall, but as I say, the clutch itself seems to be operating fine, just much stiffer ?

Does the lever have free play? When the clutch pack gets out of spec (You have to check the finger height) it can become hard. Either the clutch lever was adjusted wrong or it`s time to pull the clutch and bring it back to proper finger height.

Clutch pack out of spec ?

Also, can you explain about bringing it back to proper finger height ?

Usually most buy a new clutch pak. Originally you could buy different thickness of steel plates, but I forget what year there was a change. Some people who have been Gasser riders for awhile are very use to this issue.

http://www.gasgas.com/Pages/Technical/Pro/clutch-measurements.html

That all sounds a bit technical for me.

Can you explain why this would be needing changed if it was fine until very recently ?

First, did you check for the free play at the lever? When the finger height becomes lower, the leverage decreases which makes for a harder pull. This happens when the clutch pack swells. Which can happen even with out riding.

There was free play on the lever, however, this is actually my partners bikes, and with having female hands, which are small, the position of the replaced lever sits too far out for her small hands. Though even I have noticed how much heavier it has became since putting on new lever.

That has always been a problem for the PRO. People with small hands adjust the lever too much. The piston in the master cylinder has to return all the way to work properly. Just the nature of the machine. I have seen many women riders switch brands for this reason.

As I say, it's been fine til then for her.

Just offering suggestions. I would still have the finger height checked, 15 minute job. The reason is if it is not correct, everything else you try will not work. Good luck

They are apreciated, though not sure what you mean by "finger height" ?

The clutch on the pro is a diaphragm type with fingers. You measure from the point below to the end of the finger. I think it is 17mm. Lay the bike on it`s left side, remove the kick starter, the clutch cover bolts, gently pull off the cover (careful of the gasket) tie the cover to the fork tube through the kick start hole. Be careful not to lose the washer on the kick start shaft. Now measure. If it is 16-17.5 it is probably still ok and I wasted your time. If not it needs attention.

Look on YouTube for jim snell. I think its clutch video part 2. he shows you step by step what to check. you will see about finger height on there.

sounds more like a problem at the lever end to me, bit of a coincidence that the pack finger height would need adjusting cos the bike has been dropped.

I would (if you havnt already) remove the small rubber boot and make sure the plunger pin is not bent or not seating in the piston correctly,

Also did pivot bolt get bent, is it binding on the nylon bushes in the lever, have you done it up toooo tight?

Good luck.

TLTEL

The finger height adjustment has been covered quite few times before, but it does sound unlikely that it is that to me, although never had a PRO myself.