Installing Rivera Primo Slime Line Bet Drive

Xavier Gets Back In Build Mode

Article And Photos By: Xavier Muriel

Originally Published In The April 2016 Issue Of Cycle Source Magazine


Greetings fellow sled heads. This month I’m going to try something a little different. As most of you know I write a column about my adventures on tour as well as visiting the local shops in towns that I’m in. But when I’m home its all about THE BUILD. This month Ben Kudon and the fine folks over at Rivera Primo have agreed to let me do a tech article so I’m going to install one of their slim line belt drive units on my current shovel build that I’ve been showing bits and pieces of here and there. And away we go… FIRST OFF- Disconnect the negative battery cable and place where it will not contact the negative terminal. Make sure your work area is clean and uncluttered.


Per OEM specs, drain and remove primary and chain housing. Make sure to remove all grease and dirt from engine, transmission and frame. Once the entire primary unit is removed you must then remove the main shaft bearing with the proper removal tool from Jim’s or various companies.


Install engine spacer and check fitment.


Install motor plate (fitment may be snug, DO NOT use a metal hammer. Only a dead blow or rubber mallet).


Install four 5/16-18×1.5” socket head cap screws into motor plate (engine). Make sure to use blue thread locker on each screw. Note: Be careful as there are two different lengths to these socket head cap screws. Some are for the engine, some are for the clutch pack area.


Tighten all eight head cap screws evenly to transmission and engine using a torque wrench set to 28-32 foot lbs.


Re-install your starter using the same socket head cap screws that were originally on it.


Install in sequence order, starter shaft coupler, 2nd extension shaft, 3rd spring, 4th pinion gear, 5th thrust washer, 6th locking tab, 7th starter shaft screw. Note: There are two different hex head lengths, 90-93 is 1/4-20×3.25/94-06 is a 10-32×3.25 then after deciding on the proper hex head screw align lock tab with slot in extension shaft and tighten to 100 in. lbs, fold the lock tab against a flat side of hex head screw.


Remove four 1/2×1 shouldered screws from rear pulley and remove spring retainer, diaphragm spring and aluminum pressure plate. *Note leave clutch pack in pulley clutch hub, now install rear pulley (WITHOUT THE BELT) onto main shaft and tighten main shaft nut. *Note the nut is left hand threads


Install front pulley with washer and nut then tighten.


Use a straight edge to check alignment of front and rear pulleys. Using the belt guide next to the ring gear, check alignment with front pulley. If the pulleys are not in alignment, use the proper shim from the shim kit provided to align both pulleys.


Remove both pulleys after alignment is finalized and install primary belt. After placing both pulleys and belt back on use two to three drops of blue thread locker on both engine nut and clutch hub nut. Torque the engine nut to 150-165 foot lbs and the clutch hub nut to 70-80 foot lbs.


Install starter support housing using three 10-24x.500 socket head cap screws. Use a small amount of blue thread locker and tighten.


Install aluminum pressure plate followed by the diaphragm spring/ spring retainer and four shoulder screws with one drop of blue thread locker and torch to 40 foot lbs. Note: You can adjust the pro clutch per manual.


Install four stand offs using blue thread locker and torque to 40 foot lbs. Install outer belt cover with four 3/8-16×1” socket low head cap screws using blue thread locker and torch to 40 foot lbs. Re-install negative battery cable and double check that all work is final.


The nice thing about the Primo Slim line is that even on an Old Shovel like mine it’s the perfect compliment, unlike some of the modern looking belt drives that may have looked out of place. You can tell the parts it’s made from are heavy and will stand up to the hard riding that this bike will be put through. Everything went together great and there were no fitment issues. Great Product, can’t wait for summer!

Leave a Reply

Your email address will not be published.