Rivera Primo Starter Ring Gear - Manual

STARTER RING GEAR REPLACEMENT INSTRUCTIONS
for PRIMARY CHAIN DRIVE APPLICATIONS
on LATE MODEL EVO BIG TWINS
Thank you for purchasing this Rivera Primo high quality replacement starter ring gear kit. Included in this kit
are a starter ring gear and the allen bolts needed to attach the ring gear to the clutch basket (Rivera Primo
recommends the use of a high quality threadlock compound (red) on the bolts when attaching the ring
gear to the clutch basket).
NOTE: Prior to starting any work on the motorcycle, make certain that you disconnect both
battery cables !
1. Remove the stock clutch basket from the primary drive and remove all the clutch plates keeping them
in the same order so they can be returned to their original locations.
2. Using a drill press, drill-out the stock rivet heads. Then using a punch & hammer, drive the rivets out which
will allow removal of the OEM starter ring gear. Using a 5/16” drill, enlarge the rivet holes in the basket.
3. Mount the Rivera Primo replacement starter ring gear on the clutch basket so that either the beveled or the
flat side of the ring gear faces inward, towards the starter, when the clutch basket is re-installed.*
4. Line-up the holes in the Rivera Primo starter ring gear with the holes in the clutch basket.
5. Using the allen bolts provided in the kit, attach the Rivera Primo ring gear to the clutch basket. Make certain
you use a “red” threadlock compound on the bolt threads.
6. Tighten the bolts down equally and uniformly until all are tight. Torque to 29 foot pounds.
7. Reinstall the clutch basket and check for clearance(standard operating procedure when installing something
new). Pay particular attention to the air gap between the front face of the pinion gear teeth and the
back face of the ring gear teeth. This measurement should be no less than .080” and no more than .125”
(optimum gap should be approximately .100”).
.
8. If everything clears, reinstall the clutch and primary drive components. Adjust the clutch, then
re-connect the battery cables. Now you’re ready to ride !
* Use of either the beveled or flat side of the ring gear is up to the discretion of the end user.
RIVERA PRIMO INC. 12450 WHITTIER BLVD. WHITTIER, CALIFORNIA 90602
TEL: 562-907-2600 FAX: 562-907-2606 www.riveraprimoinc.com
1108-0012 5/2011
HOME OF PRIMO®BELT DRIVES
QUALITY & PERFORMANCE SINCE 1973
Use an 1/8” Allen wrench to measure the gap. Just slip the short end of the wrench between the ring gear & the
pinion gear. If it fits, great. If there is too much gap, the jackshaft assembly should be shimmed to reduce the gap to
the spec above (order #1185-0500 shim kit).
Air gap between ring gear
and pinion gear
Measuring the air gap