Hello I have a 1998 Suzuki quad4unner 160 and it starts really hard and knocks when starting but goes away once it actually is running. It's running rich and the mix screw is all the way in haven't messed with the jetting. Took the carb off gave it a good cleaning still starts hard checked the valves there fine as far as I can see has spark but I can't figure it out anyone have any suggestions 😟

 

If rich with mixture screw all the way in, your carb is not set up right. Never just clean it, get a good rebuild kit and do a thorough rebuild and set to specs.