If...
1) You're in neutral..
2) You have oil in the oil tank.
3) The starter won't turn it.
4) The kicker won't kick it.
5) The drive chain is total in free movement..
You're gonna need to start looking inside the motor..
First place I'd start, I guess... would be to pull the top Cam cover off and see what it looks like in there..

Build it the way you want it ..... then learn how to ride it like you own it..
www.lowridersbysummers.com