Black Smoke coming out on 250r???

[1972mercury]

Just finished rebuilding my air cooled 250r re did the top end 70 over stock carbuetor, stock jetting, mixing gas at 40:1 and still diden't run good at WOT so went down 1 jet size 130 to 125 now it runs awesome plug color is dark brown but when I sit there and rev it you can see puffs of black smoke coming out?


125879

[muthey]

I'm no 2 smoke specialist, but shouldn't you have some black smoke with a two stroke, seeing as you are running oil in the fuel

[falloutboy]

oil burns off as blue smoke. doesn't partially unburned fuel come out as black smoke, or am I thinking diesels?

[Taiser]

Yep, blue smoke...black usually means it's too rich...not sure what it means on a stroker though, the blue should outweight the black?