Clutch problems

[hazardman50]

Hi,

I bought a 1993 CRM literally 3 days ago and on the ride home (a total of 120km) the clutch suddenly stopped working about 40km from home. Luckily I got it rolling again on some grass and got green lights all the way home changing gears without using the clutch. When test riding the bike the friction point on the bar lever was quite far out from the handle bar - something that I intended to adjust but other than that, changing gears was fine and there was no slipping at all. Everything was very smooth.

I initially thought that the clutch cable had come out of adjustment making the friction point on the further out than the lever could reach if you get me.... However, I checked that theory this afternoon by re-adjusting it on the motor and handbar lever and there was no change. The external moving arm on the motor has a full range of motion when the handlbar lever if pulled all the way in and springs back when the lever is released. When I start the bike in neutral and then pull the clutch in all the way then shift up into first the does a little skid and stalls.

Could somebody please help me and suggest what I should do next? I have little mechanical experience although my friends are reasonable with spanners.... should I try and fix it myself or get it taken to a mechanic?

Thanks guys!

Edward

[superbob]

sounds like my clutch but a bit worse first off have a really good look at the cable it could have streched. Next take the clucth cover off have a look at the plates make sure its got gear oil in it also have a look at the clutch basket for grooves were the plates have dug in. I fitted a new cable new springs and filed the grooves down on the basket and its made the clutch a lot better. Its not a hard job to do just take your time.

[SkidMark]

doesn't sound like something worn if it happened suddenly. As SuperBob said have you put fresh oil in it and if so what did you use?

[back off road]

looks like something has gone rather than worn out , id have a look before you start buying bits

[knackeredMk1]

Two things to consider -

Worn/frayed clutch cable that is not transferring all lever travel to clutch arm. Solution - replace cable.

Someone has put car engine oil in the gearbox. Big NO NO as there are 'friction reducers' in car engine oil that make a wet bike clutch slip. Solution - wash out old oil (drain and refill and drain again at least once) and replace with suitable m/c oil after replacing all clutch plates. You might get away with replacing only the organic plates though.

[fallenmikethebike]

" Changed up into first" shurly you mean down?
Car oil in the g/box? it doesn't sound from the final description that slipping is the issue.
I rather suspect that some " imaginative" repair has already taken place to get the bike away.
Remember, under law you have the right to return goods not fit for purpose, however purchased.
Mike

[knackeredMk1]

DOH . Ignore my second suggestion. Too tired, brain not working .................... .

[hazardman50]

Some quality suggestions there.

The cable could be stretched hence the maximum adjustment and far-reach of the friction point on the handlebar lever when I bought the bike, however, the when the handlebar lever is fully pulled the moving arm on the external of the motor is at its maximum movement leading to me think it is internal. I checked this by holding in the handlebar lever and pushing the moving arm with my hand but there was no movement - it was at the full range of its motion. This arm also springs back to back of the bike when the handlebar lever is released - a promising sign.

Thanks for your suggestion 'knackeredMk1' but the fellow who I bought it from seemed well versed in engines so I doubt he would have put car oil in it. He gave me the oil containers that he used with it and they are all motorcycle oil meant for 2 strokes specifically. Good suggestion though! I'll still buy some new oil - make sure it's right just to be safe.

Superbob, I like your ideas - I'll take the plate off this weekend and have a look at it. I'll check the oil and replace it and file the grooves down in the basket. What is the best way to tell if there is something wrong with the springs? If I can't see anything obviously wrong with them should I replace them anyway? I'm going to try and hunt down a cable for it though so that's the first thing I'll replace. Any tips/idiosyncrasies with these clutches when removing and re-assembling them?

Mike - I "shurly" meant down haha, I'll get cracking and try and fix it and if I find anything dodgy I'll call the seller and ask him to explain himself. He seemed pretty genuine though so it could just be a bit of a freak/unlucky thing you know...

Thanks guys

Ed

[knackeredMk1]

I don't know what else to say. The clutch release mechanism is very simple and if the arm is moving to its full extent then it is very unlikely to be a breakage of some kind.

There could be some really big grooves on the clutch drum but this sounds too severe for that.

To check you could lay the bike on the LHS and take the cluch cover off and see if there is some breakage or excessive grooving. What you need to look at with the cover off is 'do the plates get loose when the clutch is pulled in ' or 'are there deep grooves where the tongues of the organic cluch plates meet the clutch drum '.

I'm still suspicious of the cable as the arm on the engine is very very hard to turn by hand.

[hazardman50]

Ok, will do what you said this weekend. The arm on the engine was not at all hard to move by hand but did require a bit of pressure - equivalent to that of pushing a wooden table with your thumb haha not the best comparison but similar amount of pressure if you get me.
Just to clarify, excessive grooving on the clutch basket/drum? if there is should i be filling the grooves down to make it smoother?
If the plates do get loose with the clutch is pulled in does this mean it's a good thing or a bad thing? sorry for being a bit of a kook - have never had to open a clutch before...
I'm sure I'll understand once I see it but I want to get as much info on it before I pull it apart.

Ed

[superbob]

start with the cable and try that if you dont get any were you know its got to be an actual clutch fault so take the side casing off I bet you will find big grooves in the clutch basket. If it was me I would stick some stronger clutch springs in it simply because you have the clutch in bits so why re build it with the originals in it only to take it down again and put stronger ones in. make sure you use a new gasket.

[hazardman50]

sure, sounds logical.

To buy: clutch cable, springs and a new gasket.

Thanks! I'll let you know how it goes.

Ed

[superbob]

nice one mate you might also want to buy a clutch center nut aswell as they should always be changed when they are removed. You can get most of your bits from lesure trail they are pretty good. Any way let us know how you get on.

[fallenmikethebike]

Quick thought, are the fibre plates seized to the metal plates?, it's the only scenario I can think of that will exhibit the traits we have had described.
Mike

[back off road]

it may be worth looking around for the bits as personally i find Leisure Trail pricey