Here's some info from Jesse at Kientech.
1998 and early '99 were equipped with a solid idler gear that created a problem when the engine kicked back during shutdown, breaking out the gear bearing bosses. '96 and '97 had the torque limiter gear that is designed to slip due to a preloaded slip clutch arrangement. They went back to this design in mid '99 after vin # X2100561.
'07 DR 650