Motor locked up.

Hey guys I’m New to the forum, but glad to be here! Got a ? Guys, I been had my Honda rancher 350as since March it’s an 00 model by the way. Had top end rebuild, gaskets, pistons, everything, well here 2 weeks ago I pulled my bike out to my cousins horse track back it off trailer put it in 1st, scooted across the track got ready to go up a gear, damn back end lock down on me completely, thought it was my starter, had it rebuilt, works fine and replace solenoid switch, still clicking, till my father in law tells me he thinks the motor could be locked up. Any suggestions I need help guys!!