Yz450f smoking after rebuild

[Chase Goodling]

I had rebuilt my bike... rode it for around 5-6 hours so far... and its starting to burn oil (visible blue smoke). Blip the throttle and it does it. I have heard that valves need adjusted after a few hours? Hope this is true.. i dont wanna tear it back down. Please help.

[FORMA MOTO]

I had rebuilt my bike... rode it for around 5-6 hours so far... and its starting to burn oil (visible blue smoke). Blip the throttle and it does it. I have heard that valves need adjusted after a few hours? Hope this is true.. i dont wanna tear it back down. Please help.

Define 'I had rebuilt my bike'.....without some info, we have no idea how to help you.

[Chase Goodling]

Changed the piston, rings, pin, clips, valve seals, and gaskets. Just a basic topend rebuild

[Chase Goodling]

Took care of the oil problem.... but when i start the bike now it gets warm and coolant starts pushing out the overflow tube...

[antleo]

That could be normal, how long are you letting it warm up? what type of coolant and ratio are you using?

[Chase Goodling]

The coolant is 50:50 mix... but its way more than normal... looks like mtn. Dew coming out when you get on it.

[grayracer513]

If it blows coolant while you are moving, that is, you start the bike and take off before it starts overflowing and still after a few minutes you have it blowing coolant, you may have a head gasket problem.

How did you torque the head?

[Chase Goodling]

I had torqued it to the correct torque... cant remember it off the top of my head.. plus 10 degrees. When the radiator cap is off idling it doesnt push but the time you put it on it pushes the overflow... could this be a clogged radiator?

[grayracer513]

I had torqued it to the correct torque... cant remember it off the top of my head.. plus 10 degrees. When the radiator cap is off idling it doesnt push but the time you put it on it pushes the overflow... could this be a clogged radiator?

A clogged radiator would cause coolant to spill out even more with the cap off, wouldn't you think?

The correct torque process requires torquing to 22 lbs to precondition the gasket, then loosening and retorquing to 14 lbs plus 180 degrees, not 10.

https://www.thumpertalk.com/forum/showthread.php?t=972816

[Chase Goodling]

if i were to put the overflow tube in a bucket of water and bubbles come out, would this be a good indication of a head gasket?

[grayracer513]

Possibly, but steam is normal, and will blow bubbles if you do as you suggest.

Well equipped shops should have a tester to detect combustion gasses in the cooling system, which is an accurate means of testing this.