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Low compression caused my bike to not start, does this mean my top end is fried?

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Before I put my 05 CRF250R away for the winter it was running weird. I noticed it was leaking oil out of the engine cover. It was understandable because i had just put a new stator in. The bike had been running oddly for some time before i realized it was leaking. I just took the bike out for the spring and now it doesn't even start. I bought a new engine gasket to try to fix the leak. I am currently installing it. I am wondering if the low compression could've messed up the top end? I rode it with low compression for about three weeks before it started to bog so bag i couldn't ride it anymore. Will replacing the seal fix my issue or have i created a whole new one?

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Prob with the CRF250/450s is the compression release, it lowers compression below 60psi for starting. Add in some additional loss caused by a leaking valve, worn rings, or worn timing chain and you have an engine without enough compression to start. As posted, check the valve clearances first.

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23 hours ago, TownTown 250 said:

First thing I would do is check Valves, I also had low compression on my 04 and now that they are in spec it's like new

x2 on this, check your valves 1st and then do a leak test. 

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