Big problem after rebuilding old 250 polaris. 2 stroke. All new seals, checked ring and piston gaps, checked all electrical, paint, etc. Well it started with 3 pulls and ran pretty good for just getting it back together. Quite a bit of blue smoke like my mixture was a bit rich. Everything seemed fine other than the smoke. I have yet to put on the clutch pulleys or cover to give her a test drive(automatic 4x4). But after a few hours I was getting ready to put the final pieces back together and thought I'd try a start again just to see. Well, one pull, she started an ran for a minute and then the RPM's just took off like I had the throttle wide open. But it wasn't. After shutting it down I checked the throttle piston and it was working just fine. By the way no aircleaner yet also. Anyway I waited a few minutes and tried starting it again, on the ready to quick shut it down again. Wouldn't start. Checked spark and that was fine. Then after a small shot of starting fluid it fired, ran for about 5 seconds before reving up again with no throttle. It ran ok before but had no power whatsoever. The oiler was disconnected before I got it and the gas was mixed. Supposibly at 40:1 ratio but smoking. I made a cover and removed the entire oiler unit, sealing it with permatex gasket maker and the new cover. I have worked on quite a few dirtbikes in the past but never had any problems. This is my first 4wheeler and I thought it'd be a breeze to get it running decent. It was cheap. Any suggestions?

 

Your sucking air from somewhere. Could be the jug base gasket. Could be a seal. Could be a boot, but your sucking air, if like you say the carb is fine. Now you have to look around and see which one.
Your lucky; some two strokes go to the moon even with the ign shut off. When that happens, the best thing to do is run. [img]i/expressions/face-icon-small-shocked.gif[/img]