Clutch issues ty250

[tjay7]

Hi All,
I am making progress on the TY250. I have got it running nicely and now working on the next issue.
The clutch was sticking so i pulled it apart to find all friction plates stuck together. I got new plates, soaked them in oil for about 30-40 mins and reinstalled the clutch with new oil.

I now have the opposite problem where the clutch wont engage and all plates seem to be slipping. Could this be because i didnt soak the plates for long enough? I am a bit lost for where i have gone wrong.

Cheers

[David Lahey]

There are a few things that might be causing this.

It will have nothing to do with soaking or not soaking the new plates. They don't swell or shrink and will drive perfectly well totally dry

If you want you can test a TY250 clutch before putting the clutch cover back on, and in your case you can take the cover off without draining the oil if you lie the bike down flat on it's LH side with the steering turned fully to the right.

The standard clutch on a TY250A is a different design to the standard clutch on a TY250 BCD or E and runs a different number of plates

Here are some possibilities for why the clutch won't drive:
The stack height is wrong (plates too thin, not enough plates, incorrect assembly sequence)
The camshaft may be sitting in the wrong position (rotated out of position)
The camshaft (pushrod free-play) might need to be adjusted

[tat ty]

I did a clutch replacement on my TY250A model about a year ago.

Had a problem similar to your description. I had concentrated on all the plates returning in the correct sequence and orientation so was a bit stumped at first, however after the third reassembly realised that the location of the pressure plate also effected things. I rotated the pressure plate (Not sure by how many notches/degrees) and the plate suddenly dropped into the correct position.

I can recall the difference being very obvious after the event, but not so beforehand.

All good from that point on.

Alastair

[tjay7]

Hi guys thanks for your advice.
I did take note of the way each plate came off and put them back in the same position. The main pressure plate just doesn't seem to be getting enough pressure.

Alastair I might pull it apart for a third time and see if i can rotate it into a better position. I had just lined up the 3 arrows on the pressure plate with the arrows on the basket.

thanks again

[Guy53]

Look carefully at the 3rd possibility proposed by David.

Guy

[darrenc]

Hi guy i was in the uk talking to TY trials Steve martin about clutch slip and he said don't use expensive gear box oil just the cheapest one you can find and change it more often.as this fix the clutch slip on his TY's .I haven't try it on my Italjet yet as I have clutch slip on that as well .hope this helps

[tjay7]

All seems to be working alright now, although it only engages when the clutch is almost let out fully. This should just be a minor cable/ level adjustment right?

[David Lahey]

There is an adjustment for the pushrod camshaft that I mentioned earlier for you to check, that you should check.
It is located near the gearbox sprocket and looks like a 17mm or 19mm AF nut with a phillips screwdriver slot on the part inside the nut. The nut is a locknut and the screw is the sdjuster. This device adjusts the freeplay in the arm that the cable goes on, underneath the motor by lifting and lowering the clutch release camshaft. You need to get this adjustment right before fiddling with the cable adjustment or the handlebar lever. If you have a standard magneto cover, you will need to take the magneto cover and off to adjust it, and to get the adjustment right, you need to see the end of the camshaft where the cable connects and for that you will need to take the bashplate off

[Jools]

Might just add that many of us try to avoid 'Friction Modified' oils in clutch gearbox applications.
Lots of bikes are really sensitive re: the clutch and oils like GTX which have additives that can cause clutch slip.
I play it safe and use oils specifically designed for wet clutch bike engines.

[tjay7]

David,

I have now adjusted the freeplay as you suggested and seems to be working a lot better, however ill take it for a ride tomorrow and check it out. I used a 2stroke specific oil for wet clutched, cant remember the name off the top of my head though..