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Crankshaft measured, opinion wanted !

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Hi, I measured my –02 CRF (which has 70 hours of motocross use) crankshaft and got the following results:

(Measurements are in millimeters)

Crankshaft runout, left: 0.04 (limit 0.05)

Crankshaft runout, right: 0.02 (limit 0.03)

Big end radial play: 0 (zero) (limit 0.07)

Big end side clearance: 0.4 (limit 0.05)

So, everything else is OK except the big end side clearance, which is the whole 8 times over the service limit.

Do you know is this normal, any opinion? or should I really change the crankshaft as manual is suggesting?

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Id be lookin at a new connecting rod at least....

with that much side to side play, you could probably have a low pressure problem that could possibly starve the top end or the wrist pin and cause a huge expensive failure. A connecting rod isnt that much money, but the labor to swap it can be kinda steep....Id look in to getting the crank redone though for sure...

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okey, thanks. That explains why the side to side clearance is so tight. Based on the previous two stroke experience, it was not so evident to identify....

The easy way to fix side to side clearance is just to push the crank sides in the hydraulic press until the clearance is right. I was wondering that is it possible that crank sides tend to run apart from each others and then this will increase the clearance. It's hard to say, but in two strokes the crankshaft tends to open and at least those cranks can be fixed by pressing it just back

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