I have a yfz450 and it won't start. It has spark and a new spark plug but no fuel to the cylinder. Any ideas on what is the problem?

 

Check to see if fuel flows from the petcock to the carb. If it does, then I would check your float, it is probably stuck. Sometimes just tapping on the float bowl will "unstick" them, but even so it wouldn't hurt to pull it apart and clean everything up so it doesn't happen the next time you ride it. There also could be dirt in the carb.

 

I did check the petcock and am getting fuel. So I'll check your other suggestions and thanks for the quick reply.