Wr/yzf250 Clutch

[scott_king]

Hi all

I have been riding my 2006 Yamaha YZF250 for around 6 months now. I am getting used to riding a four stroke motocross bike. However in recent very wet events, I have come across the wobblers (or slow b******* as some people call them) being very slow and struggling. To keep the bike running I am having to keep applying and slipping the clutch while waiting for a chance to get by. But this quickly causes the clutch to over heat and become virtually ineffective so I keep stalling the bike. It cools down when I stop for 10minutes or after I

[woody]

I've had 2 and 4 stroke Yam enduro/motox bikes and it is common to all when the clutch is used a lot. Like you say, it overheats, the plates swell and this causes the cable to go slack as the pressure plate moves away from the pushrod end which means when you pull the lever the clutch doesn't fully disengage.When it cools the plates shrink again and normal clutch action returns.

Not much you can do about it really other than to stop and take up the slack in the cable when it happens - but then you have to let it off again when it cools or it will slip. No idea whether aftermarket plates or baskets etc will help. I just tried to use the clutch as little as possible.

Hydraulic clutches are not supposed to suffer from this as the fluid will always compensate for plates swelling and keep clutch operating normally - can still happen to KTMs though which are also only too willing to impersonate kettles when the clutches caned hard

Edited November 1, 2007 by Woody

[paulthistle]

The hydraulic clutch helps.

There is a set of GYTR inner and outer pressure plates that have little oil scoop holes to help cool the clutch. The outer pressure plate picks up the oil and delivers it through passages in the inner boss to the plates. It works well.

It can also reduce that dry clutch shuddering sound, under heavy use.