99 yamaha yz250 making noises

[romeoz13]

We are running 32:1 oil to gas ratio....but ever since my brother took out his carb to clean it something is not right. When we ride it now it makes a popping noise out of the exhaust. Before it was smooth...any recommendations to as what is going wrong...

Bryan

[2muchquad]

Make sure there are no leaks anywhere in the exhaust system.Did he do anything to the carb as far as rejetting goes?

[krt400ex]

u might need to adjust the float bowl. sounds like it could be running lean

[firefighterjosh]

Make sure when he installed the carb back on that there is no airleaks in the intake