Prarie 300 starts and idles fine. During higher RPMs the motor sputters. Drained the gas tank, fresh gas. Cleaned the carb. Replaced the fuel lines. Installed new air filter and checked the rubber intake.New plug. Any fresh suggestions?

 

Sounds like main jet or quad starving for fuel. Run fuel line from tank to carb to rule out your petcock and pull main jet.

blow out jet and opening that jet screws into. Ensure your spark wire, coil, wires are tight.[img]i/expressions/face-icon-small-shocked.gif[/img]