smoking!!

I've just gotten to where I can ride my bike again after nearly 4 months off (broken tibia), and now my bike is smoking! It was always a little rich, I just moved to a hotter, more humid area (same altitude) so I figure I can expect a little more richness. After riding the other day and seeing how rich it was, I dropped the slow jet two sizes (to a 48 from 52), dropped the needle one position (top), and the main one size (a 160 to a 150). I've got the crispness back, but the smoke is now more white/light blue color.

Will blowing a head gasket make the smoke this color? The coolant level hasn't changed and there aren't any particles floating around it. Besides, my bike has one of those aluminum gaskets. But, the gas is the stuff I mixed the day I broke my leg (four months ago). I don't plan on using this gas, but could it be the reason I smoking this way? It's a lot of smoke!

Any ideas?

It's an '01 kx250.

Anyone got any ideas on this?

I suppose it was the gas. I changed it out today, put the fresh stuff in and it's fine now. The jetting though--the airscrew is at 2 1/2 turns out now. That's where I get the max RPM's from. Is my pilot still too small? I can't believe the jetting was that far off and I've not been fouling plugs---just a little spooge on my swingarm. The screw won't turn any further than 3 turns out. I'm gonna be riding in sand a lot, so I want the bike a little rich. I think this setting is fine. Thanks for everyone's help!