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super smokey

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Got a friend with a yz 250, think its an 02.. It has strong power throughtout the rpms, it however also has a ton of smoke throughout also, even after hot.. I adjusted the fuel air mix, no change in the amount of smoke. Anyone have any ideas what is causing this?

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can you ellaborate on how i should do that.. probably a good suggestion becuase i believe there is smoke comming out of his collant overflow tube if i remember correctly

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I haven't really messed with the bike enough to know, i rode it a few times, he rides slow and i figured it wasn't getting ridden hard enough, that cleared it up a little by hammering it a little... The coolant i believe was always pretty full, and the oil i never checked

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re jet the carb to your ridinf conditions

+1 What kind of premix is he running, as some are smokier than others also, if it does not improve start looking towards the clutchside crank seal allowing transmission oil into the motor to be burned

What kind of premix is he running, as some are smokier than others also

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amsoil race oil, yellow bottle i believe. I use the same thing and mine has no smoke, can anyone explain smoke coming out of the overflow

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can you ellaborate on how i should do that.. probably a good suggestion becuase i believe there is smoke comming out of his collant overflow tube if i remember correctly

On an '02, I wouldn't be surprised if the head gasket O-rings are bad. When they do go bad, the bike will smoke a lot as it sucks some coolant into the combustion chamber, and then when it gets bad enough, the bike will start to foul plugs.

If the bike fouls a plug, and is smoking, the first thing you should do is to pull the expansion chamber and look into the exhaust port. If it's the head gasket O-rings, you'll probably be able to see droplets of coolant on the piston and cylinder walls.

Good news is, it's easy to pull the cylinder head and check the integrity of the O-rings. Should be pretty obvious if they are compromised.

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id say bad crank seal letting tranny oil in.

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id say bad crank seal letting tranny oil in.

Could be, but it's easy to check for a blown head gasket, and it's an easy fix...

I've learned from experience to rule that out first.

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