05 yz 250 motor sounds...

hey, as of yesterday i purchased a used 2005 yamaha yz 250. bike ran great and has been taken care of and it show’s in the bikes condition. today i decided to take the bike for my first ride and i rode it for awile and it was running great but then all of a sudden it stopped running and i came to a stop.. i brought the bike back to my garage and took at apart to see what was wrong and everything seems good. 160 psi in the piston, spark plug is burning nice and the crank doesnt seem to have any play in it. the bike starts right up and i can ride it jut like normal but the motor is making alot more noise than it did when i got it.. any idea what it might be? i dont know too much about dirtbikes

I hate to ask, but did you properly mix oil into the gas?

tuff to say with out hearing the "noise" but id take as many engine covers off as you can and have a look .. compare with your manual (need to buy/have/own) ... take your clutch apart, drain the oil ..

that being said .. my guess is you didn't put the power valve back together right or something came loose ( giggiddy)

1) dose the bike make the noise at idle ?

2) can you isolate where it's coming from?

yes gas and oil were mixed properly. motor still runs like normal and idles i cant find anythign wrong. took the reeds out and didnt see any issues. where is the power valve? iv never really looked into bike motors before just alot of snowmobiles.. im guessing the power valve is the thing right above the exhaust at the front of the motor? just looks like a metal plate?

yea thats it theres a side cover on the right side too that has the linkage for it yz's are really easy to work on .. did you take the cylinder off ?

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