I posted my experience solving the starter relay sticking problem, I believe in the Bullet UCE forum as a reply. Hopefully searching on "starter" will bring it up.
Reader's Digest summary: solved by replacing with Yamaha starter relay assembly 4KD-81940-00-00. Directly replaces the one installed at factory (some of which seem to stick--doesn't appear I'm the only one who couldn't get starter motor to stop after starting the Bullet engine).