sticky vavles

hey i dont know if i just have a weird prob or what, my bike is maybe a month old a 2002 yz 250f i went to ride it one day satrted fine then started to act up a lil it wouldnt run unless i had the choke out if i turned off the choke or gave it any gas, it would bog out then just kill, also it had no compression once i got it back home, so i took apart everything the air box, into the carb on the valves and the top of the piston are all really sticky, im hoping this is my only prob, is it possible i could have over oiled my filter and sucked it all into my motor and gummed up everything so they were sticking and not opening, what do u all think,

also is there maybe somethign i can run through it while its running to make sure all the gunk gets off the valves??? any help would be appreciated

If the choke needs to be on when the engine is up to normal temperature, this would usually a sign that the pilot circuit has some restriction. Using the choke offsets the lean condition caused by the lack of fuel normally supplied by the pilot circuit. Why your loss of compression happened is a mystery to me.

Sounds like you may have diagnosed the cause in the form of too much filter oil. Has the compression come back or is it still non-existant. There are lots of possibilities but my scenario went like this. Rode the bike for the first time (it was used but had sat idle for quite some time), ran great. Let it set over lunch, tried to start it, no go. Realized it had no compression. Long story short - bent exhaust valve, probably due to a sticky or faulty valve stem or stem seal. Not all that hard to fix if you have some time and a Clymer's repair manual. Total cost was $200 in head repair costs. Good luck, hope your luck is better than mine.

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