I have the very same problem with my G2. I had a minor crash and repalced the broken parts. After replacing the parts, one of which is the main gear, I fired it up and it started an uncontrolable clockwise spin. This amazed me as it is against the torgue of the main blade. The tail rotor seems to have no effect in trying to correct the spin, however I can make it spin faster counter clockwise with the tail rotor. My tail rotor servo does not seem to center itself when I center the stick. Does this happen to yours as well? Do you know where (online) I can find a manual for the G2, mine has seemed to have grown legs and ran away.