No Clutch

[grahambaskin]

Hi guys,

my little brother has a sy250 2005 he saved real hard for it, but is getting turned off trials by the way its behaving on him. he has had a few minor problems with it all from him falling off but this cultch is a no go. At first we thought it needed bleed, tried this for ages with no joy. the slave cylinder does not move at all when moving the clutch lever. when we were bleeding it there seemed to be no pressure when i would release the air (just a drip of fulid would this be normal). anyone with any ideas or have had this problem. Does he need a new slave cylinder? how much are they?

[max1956bikes]

sounds like master cylinder problem.you could try using one from another bike,if that gets pressure up your old master needs new seal kit.fairly cheap and easy to do.

[steve]

If a little problem like this is putting him off Trials then perhaps Trials is not for him! crashes are part of the sport and good regular maintainance is very important.

However don't despair - help is never far away in the trials community and if you don't get it sorted from your query on here then ask for help at your local club Trial.

For starters try this-

I am not familier with the clutch on this model but hydraulic clutches are fairly simple and rarely give too many problems. Take the whole assy off the bike. Strip the slave cylinder apart and clean, you may need an airline to blow the piston out, be carefull. Inspect seal and look for signs of leakage. Clean up piston and re-assemble.

Clean out the hose and Master cylinder checking seals etc...

Rebuild assy and refit.

fill with fresh oil and bleed. If it still won't bleed then you may have an airlock. Try and back fill the system with a syringe from the bleed nipple. Then bleed in the conventional way.

Good luck.

[renegade]

Hi Graham

I had similar problems with my Sy250 04 clutch.

Again they came immediately after falling off and confused the hell out of me.

Firstly the likelyhood of finding a bleed nipple are slim, its a self priming system and you should avoid removing it from the bike if possible. I will assume that you have figured out how to get to it all by removing the airbox cradle, swinging back the rear shock and removing the carb.

Several things to check/do

1 You have a circlip in the slave cylinder. It may have been lost or broken when he fell off.

2 To prime the system you have filled the reservour and place the reservour and lever below the height of the slave cylinder, pump fluid through the system with the slave piston out and secure the clutch lever in the closed position, then slightly release the pressure on the banjo joint at the reservour - insert the slave piston and push it in as far as it will go and hold it there (you may need help) then tighten the banjo bolt again, reinsert the slave cylinder circlip. reinstall lever on the bike. No need to remove slave cylinder from the bike.

3 Leave overnight with the bike upright.

4 Check that the clutch lever has slack when in the released position, ie. it is not under any pressure to the master cylinder when fully released. If it has no slack when fully released the quantity of fluid in the system is increased slightly with each stroke of the clutch lever and eventually the slave cylinder will jam against the circlip. Then when you fall off the circlip is shoved out/broken and the slve cylinder gets jammed.

I'm not sure where you are but I have had a similar problem with mine in the past, and I will be pulling mine apart later this week having bent it at the weekend if you feel its worth the trip to see what I mean.

regards John

Edited September 30, 2008 by renegade

[renegade]

Eureka moment

I have been working on this problem for a while and finally I have the reason why this happens.

Basically take all the things you have read about sorting out the Scorpa clutch issues in the past and keep them in mind as they are all valid. However I have missed out one thing that came to mind when I was told of someone putting a nut on the wrong side of the lower clutch adjustment. Bending levers. The common comment was that it all happened after falling off. The answer is that the lever bends away from the handlebar creating a slightly longer stroke of the lever than should be, therefore too much adjustment. If the lever is bent towards the handlebar this produces not enough adjustment, hence putting the nut on the wrong side.

The lever should be almost straight and not pointing forward or backwards.

Wind the top clutch lever adjuster right out till it has no effect on the clutch adjustment and is slack. Pull off the slave cylinder dust boot and pull the clutch lever in until you can see the shoulder of the slave piston behind the spring clip, you will need a lamp to see this detail, (NOTE: the lower adjuster should have about 3mm of thread showing). Try to leave about 1mm of space between the shoulder of the piston and the spring clip, put a cable tie around the clutch lever to keep it in this position. Now look at the space between the lever and the handlebar. If you have any space the lever has been bent away from the bar during your little mishap.

If you have not been able to see the piston reach the 1mm from the spring clip it has been bent towards the handlebar.

Make a mental note of how much you need to straighten it (keep the cable tie you may need it again) remove the lever and heat it up before bending straight. Try a little at a time.

Having done this I now have a sensible adjustment range both top and bottom and it works perfectly.

A last word of warning, I think my bike has had a new clutch lever at some point and that may not have had exactly the same lever angle as the original so I wouldn't just count on a new one being as it needs to be on the bike.

I hope this helps fix your problem and would appreciate hearing you comments.

Regards John