How far to shim and be safe

As the title says what is the smallest shim you guys would use without fear of catastrophic failure?

I am helping a friend with a 450R he bought used; it became hard to start so we checked the valves. Both intakes zeroed out.

We tear into it last night to see what shims we would need. It has 145’s in it now, according to my calculations it would take a 130 to get them close. Is this too close to risk it?:thumbsup:

At best it would be a temporary thing before the valve(s) went to zero again, probably could get a few more hours of ride time but now would be a good time to tear it down and fix it. Otherwise knowing that the valves are worn and have sunken into the seats, obviously would be a good idea not to run high rpm if it will be ridden for awhile more before making needed repairs. I would tear it down now.

I second the previous post! A 130 is way small!

I agree with you all as well, he has decided to exercise some patience and order his parts.

Yup valves are done.....time to puit new ones in before he wrecks those seats.....maybe too late already....

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