06' 450f issues

[planetwister]

bought this bike for $2000 2 days ago. i knew it had carb problems when i bought it. i pulled off the carb and cleaned it with carb cleaner. i dont know much about these carbs so i didnt take much apart. i put it back on and it starts when u kick it and give it gas, but you have to keep it revved up like a 2 stroke and it pops/ backfires really bad when idling down. he said he let it sit over summer with gas in it and the petcock on and it has done this ever since.

The guy i bought it from had put his buddys carb on it and it ran like a top. so i know its the carb. so whats wrong with it??? thanks guys

Edited June 14, 2010 by planetwister
adding info

[grayracer513]

If you removed the TPS to clean it, leave it disconnected until you can get it running well enough to adjust it correctly according to the manual (download one here).

The two most common problems are a wholly or partially blocked pilot jet or a pilot screw assembled wrong or misadjusted. Another common error is installing the vacuum release plate on the engine side of the slide upside down.

https://www.thumpertalk.com/forum/showthread.php?p=3710599#post3710599

https://www.thumpertalk.com/forum/showthread.php?p=8021726#post8021726

http://www.thumperfaq.com/jetting.htm#PJ