If it's the big gear on the back of the flywheel, it's called the starter gear. The reduction gear would be the gear between the starter gear and the small gear on the end of the starter, itself.
I'm not really familiar with the 450R, but that's how all other ATVs are set up.
Most 4-wheeler problems are caused by a loose nut connecting the handlebars and the seat!!
You only need two tools in life -- WD-40 and duct tape. If it doesn't move and should, use the WD-40. If it shouldn't move and does, use the duct tape.
Last edited by Helmut; 06-04-2010 at 12:02 PM.