I have a two stroke 66cc running on 32/1 it has been broken in for a while and the only real ishu I have is that it 4stroks at w.o.t and I've tried moving the c clip and ajusting the screw on the side of the carb and still no diferance... any ideas?
Mine did that, it was from an air leak. The intake tube was loose from the engine, and rattled around. Make sure that's tight, and get an o-ring for between the carb and intake tube. Also I drilled my jet bigger, and I had problems, so I put another one on from a snowmobile that was smaller, no idea what size it was.
Concerning the 4-stroking engine. If you want to try a different jet Spooky Tooth sells jets that you can use as a replacement for the factory jets. For comparison the factory jet diameter is 70 (I'm not sure if that means .70 mm or what).
You could always give it more air to accommodate. I drilled some holes in the back of the black stock filter housing. I also drilled a couple small holes in the disk baffle in the end cap of the exhaust pipe.
zoooom !
It stopped that full throttle stumble.
If you got one of them fancy hi flow chrome air filters it would also increase the air and more then likely even you out.
Try this for me. Take the air filter cage right off and ride it down a clean street and see if the stumble is still there. Dont ride it for long with out the air filter , just long enough to see if it stops.