carb problems 80 RM250

Anybody got any tips on constant loading up problems with this bike? I have just rebuilt the top end, replaced the float valve and seat, set the float level to recommended height, and replaced the air filter. The pilot jet is a 60. At very low rpm, (it does not have an idle screw, so just enough to keep it running), it seems to be ok. But anything above that, but not WO, loads up, and if I do not clean it out with a WO run, it will foul the plug. Since WO seems okay, I think the main jet is the right size. Is the pilot too large? I am restoring this bike, but unfortunately, it had set up about 8 years before I got my hands on it. Any advice appreciated.

Thanks

Thanks for the response, Evoracer! In the meantime since I made the post, I was able to find a new carb for the bike on ebay, and it took care of all the problems! That thing idles, and pulls smooth through the whole rpm range. What a difference a carb can make! It starts and runs as good as any new bike now.