what more to order?

Your valve clearances are your indication of wear at the valve face. Usually, the big YZF is set up when the valves are installed, and they then don't need an adjustment for a very long time. Check them periodically. Once they start closing up, start keeping closer track of them. For example, if a valve that started out with a 180 shim one day needs a 165, it's a good indication that it's time to replace them.

Stainless valves can be used, but I don't see them being any more reliable or durable than Yamaha's OEM Ti valves are.

how do the "normal" valve wear show? is that the need of thicker shims?

My bike went bang on sunday !

Thankfully not such a big bang but the piston has been running in the bore at a 45 degree angle, and is therefore fairly knackered, the piston rings were wrapped around the conrod the bore was very scored and the head has been hit with the piston just missing on of the valves, however the botton end is fine! just stripping it all down to make sure all is ok!

olliemills <- "Not such a big.." .... i think that sounds like the whole top end ... expensive .. :thumbsup::thumbsup:

how do the "normal" valve wear show? is that the need of thicker shims?
Yes. How much thicker is an indication of how much wear has taken place.

grayracer <- ok, thanks! i´m checking the valves when i change the cam chain...

btw, is it possible to change the cam chain without removing the engine from the chassis?

Absolutely, yes.

Go back and look at my write up of the procedure on the second page of this thread. No need to remove the engine at all, and the whole job will take about an hour if the valves don't need an adjustment.

grayracer <- thanks again!

Yes. How much thicker is an indication of how much wear has taken place.

No, you need thinner shims to maintain the clearance.

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