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01 250f 60psi compression

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last fall i dropped my bike in a mud hole and it got a drink of water checked the compression the other day first kick i was getting 20 psi and the most was 60psi has this ever happened to anyone i figure worst case bent rod ? best case just broke the rings ? not really sure any tips?

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I assume this is an '01 YZ250F. Have you switched cams to have an auto-decompressor? I ask, because that bike doesn't have an auto-decompressor to confuse the issue.

Are you holding the throttle wide open while kicking? If the throttle is closed, the engine can't pull in air to compress, and you get an inaccurate test reading.

If the throttle is wide open, and there is no auto-decompressor, then yes, something is damaged. Broken rings or a bent rod are equally likely. You won't know until you open it up.

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2001 yz250f stock cams there was no carb on when i checked the compression

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thats always good . Anyone replace just the rod before or is it just as cheap to buy the whole crank assembly?

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the entire crank assembly is under 200 and comes balanced. by now it should have needed replacing anyway do to wear on the cam gear. if it has any hours on it. drop in a new(er) exhaust cam along with the new chain and much needed piston and rings.

good chance you'll need valves and do the valve springs at the same time along with seals.

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my local dealer said 112 for just the rod 514 for the assembly and buddy said there prices from three years agoso could probably add 10 % on top of that

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my local dealer said 112 for just the rod 514 for the assembly and buddy said there prices from three years agoso could probably add 10 % on top of that
Motorsport outlet sells complete top-and-bottom re-build kits that include everything except the valvetrain components.

Don't forget to replace the cam chain.

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Lukes Racing sells a complete bottom end kit for $450 including a hot rods crank, main bearings, gaskets, and flywheel and nut to make the 03-05 crank work in 01-02 engines. That might be something to look into.

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my dealership here sydney nova scotia 514 dollars guess there ripping me off ehh

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