i think methanol is similar to alcohol where you burn twice as much fuel per air but get 10% more power.
i think you are running hotter also ? maybe go leaner on the fuel? and possibly a hotter plug? try calling a dealer that actually knows what there talkling about. io would say that its popping because it is running leaning as is. wheere if it was running really rich it would bog. reply with the results when u find out whats up. iam curious