I have a 2007 chinese roketa and have problems with it running correctly due to the carb i believe. I have read the articles that 2manytoys has posted and although they seem very helpful i still have some questions.You mentioned several different adjustments but mine only has 2 being the idle screw and the one with a spring at the intake i believe to be the air intake. It is a 250cc can you help me out please.

 

If carbs on the chinese bikes are wearing your patience thin, you can always just purchase a new one. I bought one for the CoolSports 250cc model I have, for $45. It was cheaper for me to purchase a new carb, than it was to have most places even take a look at it.

 

the little front skrew is the idle air mixture skrew the rest is replacing jets