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06 crf250r crank issue or head gasket?

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first off like to say hello to all of you its been awhile and your knowledge is awesome.

so i just adjusted my valves on my 06 250r it was running awesome untill i let my squid brother ride it. he took it out for some wide open riding and it stalled on him. long story short i took it back apart the valves are fine but it has other issues. i found some brass looking metal shavings in the oil around the cam also it will only start for a few seconds before it dies. then when you try to kick it over again its really hard like maybe crank bearing going out or wrist pin in the piston. i also noticed a oil like filmy mess in my radiator cap. i did change the coolant and it didnt look like any oil was in it. im just wondering what to do from here or if anyone knows whats the issue. its not locked up but after the first short start it gets hard and acts like it will lock up.

porbably gonna be a costly repair and im a broke ass hillbilly. this season will suck without my dirt bike.

should have stuck to the 2 smoker :banghead:

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Since you found something other than coolant in the cooling system, I would start with a cooling system pressure test. This will tell you if you have a leak in the cooling system. From there, the engine wanting to seize, or lock up, could be many different things. I would at least tear the top end down & check the condition of the cylinder & piston & rings. At that point, you can check for excessive play at the connecting rod.

Good luck with your project. And yes, you probably should have stuck with your 2 stroke! Thank God I did not sell mine when I got a CRF250X... I was able to ride over the 4th weekend because I still had my 2T because my CRF is broken down waiting on parts.

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Sorry man sounds like some dumb luck. Bigborethumpers.com has a killer deal on cranks if you do need one. $178.72. I AM TELLING YOU IT IS NOT THE BIKE. I have about 4000 hours on my stock 03 crf 450 crank with not a single issue. And I attribute it to frequent oil changes. Just think. Your CRF 250 has separate motor and trans oil, just think if you had one of those junk yams, slowzuki, or kows. They have one oil for both. And I don't know about you but clutch dust in my bearings does not sound good. But all that aside these cranks do fail. It happens. Please let me know if I can help.

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first off like to say hello to all of you its been awhile and your knowledge is awesome.

so i just adjusted my valves on my 06 250r it was running awesome untill i let my squid brother ride it. he took it out for some wide open riding and it stalled on him. long story short i took it back apart the valves are fine but it has other issues. i found some brass looking metal shavings in the oil around the cam also it will only start for a few seconds before it dies. then when you try to kick it over again its really hard like maybe crank bearing going out or wrist pin in the piston. i also noticed a oil like filmy mess in my radiator cap. i did change the coolant and it didnt look like any oil was in it. im just wondering what to do from here or if anyone knows whats the issue. its not locked up but after the first short start it gets hard and acts like it will lock up.

porbably gonna be a costly repair and im a broke ass hillbilly. this season will suck without my dirt bike.

should have stuck to the 2 smoker :banghead:

Brass looking material is a good sign the connecting rod big end went or is going. Get an OEM crank. I run Hot Rods cranks in just about every bike but the Honda's. Honda makes a good, reliable crank so I dont go aftermarket with them.

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Put it on a stand, put it in gear, take out spark plug, and spin the rear tire. Try it backwards and forwards.

If it spins freely (it will have a bit of drag but shouldn't catch on anything), it probably isn't the crank.

If it spins freely and then catches then you probably need a crank.

IMO, I think you need valves. You mentioned that you shimmed them, which means they needed to be replaced, not shimmed. It seems impossible but they can zero out again after only a few minutes of running.

Best idea is to take the top end off and inspect everything.

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Thanks for all the info guys I'm gonna start taking it all apart tomorrow and inspect the entire engine. It was a old arenacross bike with the engine built by pro circuit. It's almost totally aftermarket parts on the bike. Makes me worry more just because its not a stock engine. I had a nice 06 ktm 250sx i traded for this bike. It was all good till this mess. Wish i still had my ktm.

Thanks again fellas and I'll probably be asking allot more questions.1373341290613.jpg

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Rule #1 of buying bikes is not to buy race bikes.

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Yep i agree. Just because it's all tricked out dont mean it runs like a champ. It ran awesome for around 15 hours since i got it. I'll fix it up and get it back on the trail.

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Yep and it hangs up. It rolled freely for a few turns but now it just hangs up. So mudguy you think a new crank?

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Yes, it is most likely the crank. It is probably the big end rod bearing. You will need to split the cases.

You won't really know what kind of damage it is until you take it apart.

Before you take it apart, measure the valve clearance and write it down. Once apart, measure the valve shims and post the measurements here. You don't want to rebuild the bike without checking out the valves.

You are probably looking at a minimum of $500 for a crank and a top end.

How often do you change the oil in the bike and how much/what kind of oil are you using?

I'd be interested in seeing some pics of your crank when you pull it out. I have some theories on crank failure i've been trying to validate.

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BTW, if you bought it from a racer, maybe give him a call and see if he'll help you out a bit, maybe he can set you up with parts or something. Worth a shot.

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I have logged everything down since i got the bike. I'm very good on fresh oil every 2 or 3 rides and i keep a clean filter always. I'm picky about my bikes because it cost to much to fix when you get lazy. I think i used belray synthetic in the oil side and maxim sync clutch side.

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I will double check the valve's and shim size once i take it apart. Might start tonight but i can't see rushing to take it apart if i cannot afford the parts yet. But i also need to know what i have to buy. This just sucks all around. Kinda bummed out because i love my dirt bike.

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Im a firm believer in clean oil. I have an 03 CRF 450 with the stock clutch in it from when it was new. and i have to many hours on it to keep track of. And I run just the plane honda oil. Non syn. I know this doesn't help your crank any. Sorry bud.

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Y'all are a huge help to me. I'm glad thumper talk is around for all us die hard riders. We all need more knowledge imo.

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I started to pull the engine last night and when i looked in the exhaust port there was allot of tiny metal shavings stuck around the sides. I didnt get far enough to check the piston and valves but it ain't looking good.

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