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crf450 all valves zero'd?

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2008 crf450

50hrs, all orginal components

local c class rider, weekend warrior, non racer

well maintained

I adjusted the valve after 10hrs, and checked at 20&30hrs no problem, though the last 20hrs the all the valves zero'd, should i shim and check again more frequently?

also whats your opinion on the piston and crank replacement intervals for my skill level of riding.

thanks

rod

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I would check them again and make sure it is not tdc on overlap , it is rare that all valves would zero out , and if they were all zeroed out it would probably not start , on the crank 50 hrs is nothing , they go 200hrs or more in allot of these bikes

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Make sure you are at TDC of compression. The cam lobes should be pointing up and back, not down and to the front.

If all your valves are truly zero'd out, it's not a matter of checking them more often. Your valves are shot. The fact that you had to adjust them at 10 hours, and that they are zero'd out so quick makes me think something is wrong with your head, and how the seats were machined.

This wouldn't be the first time I've heard of improperly machined seats on an '08 Head.

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2008 crf450

50hrs, all orginal components

local c class rider, weekend warrior, non racer

well maintained

If all your valves are truly zero'd out, it's not a matter of checking them more often. Your valves are shot. The fact that you had to adjust them at 10 hours, and that they are zero'd out so quick makes me think something is wrong with your head, and how the seats were machined.

This wouldn't be the first time I've heard of improperly machined seats on an '08 Head.

The head hasn't been rebuilt, correct? It's all OEM, and seats haven't been cut. Sounds like dirt has been slipping in somehow if you're sure you measured correctly.

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