Rivera-Primo Brute II Install

We have a goofy Shovelhead in the Bikernet shop called the 1928 Shovelhead. It has 21-inch wheels front and rear in a Paughco rigid frame, but some 1928 elements were used, including the re-pop semi-flat sided tanks, the rear fender and perhaps the seat. The bike was conceived by Bandit the bastard, built by the crew at Rick Fairless’ Strokers Dallas, with the help of Randy Simpson who manufactured the handlebars.

The bike has contained a couple of hiccups and hasn’t been ridden much. Recently, one of Bandit’s friends needed a ride, so Bandit shipped this puppy to Washington. Richard Kransler installed new Avon tires and took it out for a spin. Unfortunately, the early Rivera-Primo belt, stuffed into the semi-stock inner primary, snapped and the 1984 Shovelhead was garaged. More recently, Richard concocted a deal with Bandit for a van in exchange for his Sturgis Shovel, and returned the 1928 Shovelhead to the headquarters, where the gang went to work on it.

With Richard’s info, and after consulting with Ben Kudon at Rivera-Primo, a plan was put into motion to make this wild puppy more rideable. We needed to add an oil filter, rerun the oil lines to reduce heat, fix the sumping problem, replace the primary drive, and then we discovered a loose valve seat, but we’ll get to that.

This is also a two-part tech. We first installed the Brute II Extreme Belt drive with a 1 ½-inch wide 11mm belt with electric start in the closed primary. Then we will install the most magnificent Rivera-Primo Pro Clutch. Since this is a jockey shift, it will be interesting to test both the stock clutch against a new clutch system that’s state of the art. We will forward all of our extensive reports directly to the boss and all Bikernet readers.

We discovered immediately that the front Brute II pulley was larger than the previous model, which was disappointing because it called for more clearance in the case, which weakened one of the primary fastener locations. Not a big deal, so we went to work with a pneumatic cut-off blade and emery wheels.

It’s critical to disconnect the battery, especially while working on the inside of any Shovelhead primary. It’s too easy to bump or pull on the starter solenoid, and you could lose a finger pronto. Fortunately, we have a selection of JIMS tools and pullers for this operation.

Here’s the fine print from Rivera-Primo: Primo Belt Drives are designed and engineered to correctly fit stock Harley-Davidson motorcycles. Aftermarket frames, primary covers, engine shafts, or clutch hubs may cause installation problems. Also bent frames, sagging motor mounts, worn transmission mounts, and other defects may cause shortened belt life due to incorrect pulley alignment.

If you have a stock system being replaced, here’s the dope: Remove the front pulley, chain, compensator and chain adjuster. Remove oil lines to primary and plug or clamp to prevent leakage. Cut the chain oiler hose 3 inches from the oil pump and permanently plug it. All belts must be run completely dry, without lubrication of any kind. Therefore, remove all oil from inside the primary covers.

The spacer behind the front pulley should be removed before installing the belt drive. This spacer may or may not be required to correctly align the pulleys. If a spacer is needed for alignment, various sizes are available from your local Primo-Rivera dealer (part number PX-1, is a package of various sizes).

We discovered a very tight belt. We had to carefully install the belt in the case first. Then the front pulley was installed onto the main shaft, but just slightly to afford us some flexibility with the clutch hub. We re-greased the bearing on the clutch hub and inside the clutch shell. With the handle of a plastic hammer, while prying it with a large screwdriver, we were able to drive the clutch shell over the hub with some gentle persuasion.

We tracked the belt, and installed the same spacer from the last system behind the engine pulley. With the bike jacked and the plugs pulled, we turned the engine over to test the running direction. We made sure to run the engine over in a forward direction. It’s not a bad idea to use a straight edge at first to make sure the pulleys have the proper spacing.

“Spacing the motor pulley outward will cause the belt to track towards the outer primary cover,” said Ben. “If spaced too far out, the belt will rub on the inside of the clutch shell.

Then we attempted to install the outer, aftermarket tin cover and discovered a significant problem. It rubbed against the clutch shell. So far, our inner primary clearance adjustments worked.

We were concerned about the tightness of the belt. It seemed severe to us, and to Bandit. According to the Brute II directions, the belt requires a minimum of ½-inch up and down play at the center of the belt, and up to ¾-inch. We barely encountered ¼-inch of tough play. “Free play is critical,” Ben said, but when Bandit questioned him, he muttered something about ¼-inch being okay, since the belt was so stiff.

The crew even considered replacing the system with a stock chain, to avoid issues. We took the system apart and studied each element, and investigated. I looked into a longer belt, or installing the earlier unit again, which had its benefits with the smaller engine pulley and tapered clutch shell that fit in the primary. We installed the belt again and tested the flex—still tight. We cut a hole in the tin primary, eliminated that problem and affording us tremendous venting. We live and breathe by the Optimist Creed, sort of code of the west. We are hoping once the belt settles in and warms, we will encounter additional flex and no stress on the engine and trans bearings.

“This is a much stronger, more technically advanced belt over the previous 14mm belt,” Ben assured me. We will give it a shot. Venting is a critical element. Primo recommends venting enclosed belt installations to allow cool air to circulate into and out of the primary case. This will keep heat expansion to a minimum and extend belt life.

Special Note: Big Twins from 1969 require a #16657 motor seal. Next we will install the new Pro-Clutch from Rivera Primo and test it, so we will be in and out of this primary case and reporting back on our findings.

In the meantime, we rerouted the oil lines, added an oil filter mount, and an oil pressure gauge for more capacity, cooling, and cleaner oil. We worked on the sumping problem, and then discovered that a valve seat was loose in the rear head. We pulled the heads and delivered them to Branch O’Keefe for repairs.

Our shop intern and overall handy-man, Kyle Olsen, our official Bikernet electrician, will test this bike. We are determined to make it a solid rider, and Kyle will bring us reports and handling complaints in the near future.

We modified the jockey shift and added the 5-Ball for easy shifting that’s out of the way of our thighs at stops.

And Bandit has a code, a good one. All bikes need rear chain guards, and this bike doesn’t have one. We will remedy that. Plus we have a brand new set of Nology plugs and plug wires to install. Hang on for the next report.

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