evo pinion shaft diam : V-Twin Forum: Harley Davidson Forums

asdco · 08-10-2009, 12:25 AM

Is there a difference in the pinion shaft diameter (the pinion gear and oil pump gear) in the early evos,up to 90, and the late evo after 92? or can someone point me in the direction to find this out? Thanx

kennyflhr · 08-10-2009, 04:46 PM

Yes, the older ones were a tappered shaft. The 92 & later were a smaller straight shaft.

claydbal · 08-10-2009, 07:30 PM

asdco, you had a few (all) posts that showed you were brillant when it came to HD motors, why ya ask? not picking, just curious.

Andre' · 08-28-2009, 05:38 PM

asdco,
I have some info for you and anyone else who needs it, that is apparently not printed anywhere as I spent the last several months trying to figure this out. 91-92 EVO cranks use a pinion gear and pinion that is for those 2 years only! It is like the earlier gears in that it uses a pinion nut that is recessed into the gear but the 91-92 pinion is not tapered as the earlier ones were. In 93 and on (this is the info I took great pains to figure out) the pinion shaft looks identical to the 91-92 but it is 1/4" longer in the non-threaded shouldered portion of the pinion. This is to accomodate the new style gear that does not have a recess for the nut. The idea was to give the nut more contact with the gear. Because the gear is not recessed it moves the nut out further on the pinion. Thus the extra 1/4" shoulder. The threads for the nut are also different. The 93+ nut is a 5/8 course thread not fine.The cam cover is also different from 93-on as clearance was needed for the larger nut type.