resurrecting this old thread because i've got the same problem 2door had.
switched my old motor from Valvoline 32:1 to opti2, and just couldn't get it to run right.
it had about 1000 miles on it, and would do an easy 35mph, good power all around, etc.
put the motor on my new build and put opti2 in it at 100:1, and the thing just wouldn't run right. tried everything i could think of, 'cause i didn't believe it coulda just been the oil. ported the intake and exhaust, matched and polished the transfer ports, re-did the carb, moved the needle all over, messed with the gap on the plug, and nothing (i did all this one step at a time, so i'd know if something worked or made it worse.) i also ran about 2-1/2 tanks through it.
so i finally decided to drain it and put some old gas in it that i still had, with my old mixture, and rode off.
bogged like crazy, no power at all, and i'm thinking G0&*%&mm$t, this motor sucks.
then, all a'sudden, it just took off, and banged back to life. lotsa power, smooth idle, quick throttle response, the thing works great! doesn't have much bottom end, but i've got a 32t sprocket on it, so it takes awhile, and this motor never was torque-y anyway.
so, i still love Opti2 in my other bike, which was broken in on it and never had anything else, and still runs like a dream, but i can't recommend switching to it after your motor's been on something else. just my experience, but it confirmed 2door's problems as well.