Z1OwnersClub GB

i have recently changed a couple of valves and fitted a new cam chain.
Pete at RTT recommended i recheck shims at 600 to 1000 miles.
The valves were fitted with 250 shims and .05 gap
Checking and changing shims will not be an issue, (touch wood ...!) but my question is does the gap generally open up or reduce. (bigger or smaller shims?) Obviuosly it will depend on which face wears most but is there a general rule of thumb?

thanks guys

They wear tight , so smaller shims needed

Thanks for that Geoff, So would it be fair to assume i am better off shimming the gap to the top end of the spec i.e. 0.1mm rather than 0.05mm.
Also depending on where you read spec is either 0.05 to 0.15mm or 0.05mm to 0.1mm any thoughts
thanks

Yes Andy thats basically the way to go , but the motor may at first sound a bit top end rustley until it warms up and then quietens down .
My Kawasaki manual says 0.05 to 0.10

Always go wide.
Up to .18 if racing.
Between .10 and .15 for road.

Z1parr wrote:They wear tight , so smaller shims needed

Due to valve and seat wear.

Valve seat receeding into head.


Jimmock.

The club offer a 'shim swap scheme' to paid up club members, just contact Jerry & he'll swap 'em for free!