Got a GX200 Clone, has header, GX390 carb, 18LB. springs, air intake. Just added Mikuni fuel pump because engine bogged on bottom end (I figured this was due to poor fuel delivery). Engine runs fine with choke on and rides fine until you slow down to near stop and it just cuts out. I do not think adjusting the idle screw will help because if I increase it any more the bike will not decelerate. Any suggestions?
Engine shuts off at low RPM
- Thread starter AntZ4240
- Start date
- Tags engine cuts out fuel delivery fuel pump gx200 mikuni
Sounds like u have an air leak somewhere. Back to basics stuff here. If the engine doesn't run unless the choke is on then the engine is not getting enough fuel. This is caused by a few things. If it runs ok at higher rpms but doesn't want to stay running at low rpms then your pilot jet may be clogged or not big enough or there is an air leak in your system... Something not tightened enough or a leaking gasket. Even the smallest air leak on these engines can cause a very poor running engine. Replace all the gaskets on the intake side and make sure everything is torqued properly. Then pull the bowl on your carb and check your pilot jet to see if it is clogged. Run it and see if this takes care of the problem. If not then u need to get a bigger pilot jet. Oh and if the outlet is above your carb inlet you generally dont need a fuel pump unless u have a highly modified engine. Also check your valve lash. I like to set it at .003".