Is the air filter clogged with the 2 stroke oil? Fouled spark plug? Choke on after warmup usually means lean, but needing to turn idle high means rich. Did you get the float set right? Have you done the proper air leak test? Maybe the exhaust got clogged from 2 smoke oil? Last, hopefully not it: running oil in the gas without adjusting jets might have made it run too lean and overheat, possibly doing bad things... hopefully not that.