FOR what it is worth.
i have had trouble for a long time the engine just would not crank fast enough so i had to give it a shot if starting fluid.
yesterday i installed the motor part of the 17610 starter. i did not remove the starter from the bike. i have the bypass pipes on my 07 so i just removed the two long bolts and the nut and switched the motors. (would recommend a mechanic to do this)
this morning it made about three revs then started right up. ALRIGHT

I have an extra ground wire i think i will in stall later. and maybe rebuild the solenoid
hth herman