So here is the problem . I recently purchased a 2007 kawasaki bayou 250 . I only payed 550$ for it because it needed some work . The day i got it home it ran fine all day long and the day after that . Then the next day i went to start it and it would bog down when given throttle . I have checked valve clearance , timing chain , drained tank flushed and put new gas in , and gone through the carb about 3 times and soaked it for about 2 hours . What im not getting is the fact that it starts up revs fine for about 10 seconds then starts bogging with any throttle this pattern repeats every time i shut it off and start it back up . Keep in mind it does smoke a bit so i didnt know if it might be low compression . I'm very mechanically inclined so any suggestion is help full .

 

Some of the old Bayous eat through spark plugs. Try a new plug. see what you think.

 

I had a similar problem that ended up being a fuel flow problem. The hose supplying fuel to the carb was restricted on mine. I used a water bottle with the nipple from a bottle of gear oil to supply gas to the carb and verify that the problem was with fuel supply.