I have had this ATV for about 12 years and it always ran good with no problems. The carb started leaking so I cleaned it and put in a new carb kit. Now it gets up to 20 mph with the first half throttle and only goes to 24 mph with full throttle and that takes up to 1/4 mile to accomplish. I've tried adjusting the needle valve from 1 1/2 - 2 1/2 turns out but it didn't help. Since the old jets were clean I put them back in and tried that but it made no difference. Can anyone offer a suggestion as to what to try. I'm not sure if this problem is related to the carb cleaning or not. Thanks

 

Well if it ran good before you cleaned the carb and after your having problems.... then it just might be related..
I'd redo the carb... are the jets the same size? and if not did you put them back in the correct locations?

 

Thanks for the response. Yes the jets are the correct size and location. I'll redo the cleaning process again.

 

Make sure the boots are not sucking air.

 

Problem solved. I bought one of those longer air/fuel mixture screws so I could fine tune the setting better. It's only open about 1 turn now but it works fine.
Thanks for the comments.