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06 CRF250R Burning oil - 100cc an hour

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I have 115 hours on my 06 CRF250R, and have changed the piston and rings every 30 - 35 hours. I did my last piston and rings about 5 hours ago (engine time) and it is burning oil now. I change my oil every 2.5 to 3 hours and have never had to put additional oil in between changes. Now based on my hour meter I am having to add about 100cc every hour. The bike is also smoking a little now. I am thinking either I didn't do a good enough job on the hone last time, or my cylinder is worn out of spec, and the rings didn't seat so I am burning oil.

The bike starts cold first or second kick everytime and the bike starts right up after it is warmed up no problem. So I am not having any hard starting problems. I check the valves every 10 hours and they have stayed in spec since the first shim at 10 hours. Every time I do the piston and rings, I squirt carb cleaner in the intake and exhaust ports to see if any fluid leaks out between the valves and head, and nothing leaks, so I think the valves are still sealing ok. (not sure if that is a good poor mans test or not)

The bike also seems to be down on power compared to the previous times that I have done piston and rings on it.

Could it be as simple as the rings didn't seal? If so, with a 115 hours should I just order a new cylinder, piston, rings and re-do it?

Yea, I know it is a pain to diagnose a problem over the internet, but I figured I would throw this out there.

Thanks.

BTW.... I am a slow old VET rider, so I am not pinging my bike off the rev limiter like the kids do all of the time.

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sorry but valve seals would only make it smoke at startup. sounds to me like the ring didn't seat or you have a bad bore. hate to ask but did you make sure you didn't line up the rings.

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sorry but valve seals would only make it smoke at startup. sounds to me like the ring didn't seat or you have a bad bore. hate to ask but did you make sure you didn't line up the rings.

Yes, I had the 3 ring openings at the three different positions just like it shows in the manual. I just ordered new rings and gaskets yesterday, going to tear it down this week, inspect and re hone the cylinder then throw in the new rings and see if that makes a difference. Thanks.

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check you bore diameter while your at it you might be out of spec for standard rings. if you can't check it go to a local machine shop and see if they will ckeck it for you. your bore is out of spec at over 3.078". Or check your rin gap out of spec at 0.015"

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