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ZX9R B3/4 hydraulic clutch problem
rb968 - 1/2/10 at 04:13 PM

Hope someone can point me in the right direction here.

I have a B3/B4 zx9 engine in my MK Indy (work in progress). Originally I replaced the hand clutch master cylinder with a Honda VFr rear brake cylinder but once we bled it we found it did not seem to have the throw required and was hitting its end stop before the clutch was properly engaged so when in gear the prop was still trying to turn.

We have just replaced it with a Toyota MR2 clutch master cylinder and this has better throw. However the gearbox really thunks into first and the prop turns a rotation before the clutch works. You can get a good feel and the clutch will release and re-engage but we can't get second up through neutral. Its either neutral or a big thunk into first.

When I first got the rolling project we ran the car through all the gears using the hand clutch and it sounded fine. Its since sat about 10 months.

Any ideas on what it might be before we drag the engine out to look at the clutch plates? Could it be a selector ?

Any help greatly appreciated as am a bit brassed off !

Cheers

Rich


Peteff - 1/2/10 at 04:35 PM

If it's running get it hot and get some oil circulated before you try the gears. The plates may be a bit stuck but they should free up.


rb968 - 1/2/10 at 04:48 PM

Will try that tonight. My uncle suggested the plates might be stuck hence we pushed the rod in on the master cylinder and held it in place with tie wraps overnight as this was his suggestion of an "old trick" to free them off. Have had it up to temp already but will try again tonight.

Rich


bigrich - 1/2/10 at 06:41 PM

most Kawasaki's have a positive neutral finder which stops 2nd gear being engaged unless the vehicle is rolling.lt try raising the wheels from the ground then go from 1st to second with the wheels turning


ginger ninja - 1/2/10 at 08:09 PM

I'll second that, bigrich is right. I have a ZXr C2 in a locost - there are three small ball bearings on the transmission shaft in the gear box which stop anything other than first and neutral until the output shaft is spinning.
The clunk I found is normal when engaging first.

To try the gear selection - no need to have engine running, support 1 rear wheel off the ground.

Get someone to spin the rear wheel for you as fast as they can (forwards of course).

Whilst depressing the clutch you should be able to select up and down the box.