valve clearance

[RingoYFZ450]

what does it mean if your valve clearance is a bit tight? Intake .09, and exhaust .15. should one just shim down?

[jshtex]

As they wear the valves actually sink into the head so they get tighter, not the other way around.

So if they are tight you need to put in smaller shims and eventually replace valves and get your seats re-cut. Not cheap with the Ti valves but way cheaper than dropping one into a running motor.....

[RingoYFZ450]

Thank you for the clarification. How many times can you shim down before you should replace the valves?

[RingoYFZ450]

Thank you for the clarification. How many times can you shim down before you should replace the valves?

[jshtex]

I shimmed down untill my hot cams shim kit didn't have a small enough shim. Then I replaced the valves and had the seats redone. I actually only had one valve get that bad though. The others got tighter but only one of them got real bad. You might could buy smaller shims and keep going but I didn't want to risk it.

[RingoYFZ450]

thanks for all your info. One more question if i may. How do i tell if it is time to change the valves? I maybe have 50hrs total on the quad.

[jshtex]

Originally posted by RingoYFZ450
thanks for all your info. One more question if i may. How do i tell if it is time to change the valves? I maybe have 50hrs total on the quad.

I figured it was getting close when I didn't have a small enough shim to get it in spec. So I was tearing it appart to do a top end and I talked to the guy who eventually cut my seats for me and he looked at it and recomended I go ahead and get it done.

But if you have a service manual I am sure there are specs for the valves to tell you when it is time. If you don't have a manual you can download them on the net for free.