TY clutch

[shaunb]

A couple of questions for the TY gang….

1: The clutch on my 250D is dragging. When the bike is fired up, it basically takes off once you bang it into gear, even with the clutch fully pulled in. Once the bike is warmed up you can do low speed gear changes and pull the bike up no problem on the brakes , but with the engine off you can feel the drag when you leave it in gear, pull the clutch level in, and push the bike.

I have referred to my trusty Cycleserve manual (which is for a B model but they are the same right?)……

The pull of the lever under the engine is about 8 mm to maybe 10 mm short of the specified pull in the book (correct spec 55mm from the back of the cable retainer to the centre of the clevis pin on the actuating arm).

This makes sense as it means the clutch is not fully disengaged with the clutch lever pulled in.

My immediate thought is to adjust the cable to shorten it a little but the “good book” manual, tells me I need to adjust the mechanism itself (under LHS engine cover) to set the actuating lever where it is supposed to be (behind the clutch lever axial centre line.

Is this right or am I making things too hard for myself?

Secondly: Once I pull an engine / clutch cover off, what is the recommended way of sealing them up again when they go back together? I assume water getting in there is BAD…..

Does anyone actually use the gaskets or is a matter of hello Mr Silicone” !!!!

Any clues, answers etc greatly appreciated.

Cheers

Shaun B

[KT Mark]

Silicon is for plumbing, not motorcycles. Get a new gasket. Was the clutch operation good and began to drag over time with use? Have you done any work on the clutch recently or have you just got the bike? I had a motor cycle that had a similar problem. I found that the clutch hub nut had been loose and this had allowed the bush that the basket spins on to wear some of its overall length. It was a small amount of wear but enough to make the clutch drag after I tighted the nut. To check for this type of drag you need to remove the clutch plates and see if the clutch basket is dragging. Make sure the clutch hub nut is tight as well while you are there. What do you think David ?

[David Lahey]

If the actuating lever is too far forwards, it probably means that something is wrong inside. As Mark said it might be an issue with the retaining nut, or it might be someone has put the pushrod in without a ball, or the wrong size ball, or actuating cam might be worn down or there may be something wrong with the way the clutch was assembled or or or....
Unless we know if it is something that just happened with use, or it has been like this since someone worked on it, it is hard to diagnose the problem.
Silicon is dodgy for two reasons for that cover.
The clutch pressure plate screw heads only just clear the inside of the cover with a gasket so they might hit with no gasket (especially so if the cover has dents)
If you have to whip the cover off to do something, it won't seal without cleaning the old silicon off and reglooping it. With a good quality gasket, you can usually get the cover off, do the job, and put it back on again without breaking or moving the gasket. I've been fiddling with a TY250D clutch lately and I've had the cover off at least twice now without needing a new gasket and each time it is a five minute job (just lay the bike over on the left side).

[David Lahey]

shaunb I just thought of something else as far as the arm position is concerned. I've not had to move one for a long time, but don't TY250s have an adjustment on the clutch cam height to get the arm to the right angle? Its the nut and setscrew near the front sprocket. You didn't mention trying that.

[trialsmutha]

bet your gearbox oil is to heavy! ty,s clutchs hate heavy oil, i run ATF in mine and change it after every ride never had a problem in years! they only hold 1000cc

[shaunb]

Thanks for the tip re using gaskets, I assume everyone is making their own from gasket paper?

With the clutch though the problem is the other way around. The actuating lever under the engine is not being pulled far enough forward, even with the clutch lever on the bars pulled all the way in, it is still around 65/67mm from the cable stopper under the crankcase, the measurement according to the book should be 55mm.

This would mean the clutch is not being fully dissengaged when the lever on the bars is pulled all the way in.

Yes, David there is an adjuster inside the LH engine cover to realign the actuating lever. I was trying to avoid playing with that as I don't fully understand what is going on inside just yet......

I think I will give it a go according to the manual and see what happens....stay tuned.

Cheers

Shaun B

[David Lahey]

I reckon you are getting pretty close to working out what is wrong.
Cover gaskets were available from Yamaha dealers last time I tried.

[shaunb]

OK, this is driving me slightly nuts...

I have adjusted everything per the manual but I am still not getting enough movement at the clutch lever under the engine.

With the clutch lever on the bars fully pulled in, the arm under the engine is still about 7 to 8 short of its correct throw.

My bike has aftermarket levers, is there are correct "spec" for levers? I am wondering if different brands have a different amount of throw or pull depending on their geometry?

As a last resort are there any TY owning forum members on the Gold Coast that could recommend a local bike shop to sort this out?

Cheers

Shaun B

[David Lahey]

Yes different levers have different leverage ratios and different travel distance from "out" to against the grip. Some TY250s have had the lever arm under the gearbox lengthened.
I'm not sure of what your problem is yet. Are you measuring the travel of the cable end or the distance from the cable end from some fixed point on the gearbox?
If you want to check some things out against a normal bike, measure how much cable travel you are getting at the hand lever from out to in positions.
Another thing to check is to measure the distance at 90 degrees from the centre of the inner cable to the centre of the lever pivot bolt. This measurement should be in the range of 20mm to 24mm.
Also check the distance from the inside of the lever to the grip, measured at the point where it hits when pulled in.
Also measure the length of the clutch arm under the gearbox from the centre of the cable end to the centre of the clutch arm pivot axis.
Most likely if you are getting less travel than the book says, your particular aftermarket levers will have a high leverage ratio and/or a short lever movement.
The amount of travel of the arm under the gearbox is not particularly important because a TY250 clutch working properly will go from fully engaged to fully disengaged with that lever under the gearbox moving about 2 mm at the cable end, and most handlebar levers give way more cable travel than that.
What is usually important for the cable and bottom lever is that:
There is only about 2-3 mm slack in the cable with the clutch engaged
The lever under the gearbox is at approx 90 degrees to the cable at the point of disengaging the clutch.

[shaunb]

David

Thank you for your time on this. I suspect things are not quite right and I have a few more questions on this however I can tell you that.....

I took the new toy out for a half decent ride today and you still cant get the smile off my face. (As far as the clutch went I didnt have any problems).

My last bike was a KT and that was a few years ago now however the TY (250D) seems to have more boogie everywhere and I am surprised as how slow you can go and it still pull so cleanly off idle. Some of the banks I was playing on today were just that, open, reasonably steep banks but the TY would just crawl up them at very modest revs and just never hesitate but still instantly get up on the rear wheel with a bit of throttle.

Very confidence inspiring, now if I can just learn to ride it half well.....

Cheers

Shaun B (Very happy TY owner!)

once it am not sure