I just bought a brand new rok GP. It starts but will only run if I hold the throttle open. If you let off the throttle at all the engine stops running. I was told this is because the tolerances are tight and the engine just needs to be broken in. Is this true? I can sort of understand this, the friction between the engine parts being high. But I am not sure I believe.
I tried adjusting the idle screw and mixture screw, and the engine still doesn’t idle.
Christopher,
I’ve never had a Rok, but the reasoning here sounds bad. All the new 2-strokes I’ve ever had will idle just fine at 4K on the idle circuit of the carb. I would think if an engine required full throttle to run, it’s in bad shape. Would have to be a bad crank or the piston is dragging on the cylinder wall. Another possibility is the carb is messed up. Maybe the needles are set wrong or the carb is not properly assembled. I wouldn’t run that engine again until you can have the carb and engine looked at. Because I know nothing about you, I’ll asked if you’ve mixed oil with the gas?
Another question; do you have the axle chained to the motor and could the brakes be dragging?
Keep the Forum posted on the progress of this engine. There should more answerers coming.
Two more questions.
Did you ever try pulling up the choke lever while the engine was running and did it make any difference?
Do you know what jets are in the carb? Maybe there is someone on the forum that is in your area and has a range of jets to use.
Good luck.