1. Here is Rivera Primo's 2-inch open belt drive setup for kick-only '55-84 Panheads and Shovelheads. A simple change of the crank pulley from the '55 and up splined shaft to the pre-'55 tapered shaft would make it for early Panheads and Knuckleheads. Electric start models are also available. We also went with Rivera Primo's Pro-Clutch for '36-84 big twins to replace the ancient stock unit. The Pro-Clutch increases the friction area in the clutch by almost 50 percent while retaining easy hand or foot operation.
2. Here's what we're up against-an open chain. The shovel was converted from closed to open primary awhile back along with ditching the starter system to help lighten up the bike, but the stock primary chain was retained due to lack of funds. Well, after a few months with some saved bread it was time to make the switch.
3. We'll start with removing the old clutch, clutch basket, and clutch hub. Loosen the nut on the threaded adjuster in the center of the pressure plate. If you don't have a service manual for your bike, go buy one-now! The tear down and final clutch adjustment procedures in the service manual will be quite helpful to you, plus you should have one anyway if you own an old bike
4. A big 3?4-inch nut and a 1?2-inch flat washer together make a cheap pressure plate removal tool when the adjuster nut is put back on and tightened down until you can get the three or five (depending on the style) slotted nuts off by hand. Then you should be able to pull the pressure plate assembly off as a whole.
5. Next, take out all the stock friction and steel clutch discs out of the clutch basket. The nut holding the clutch hub to the mainshaft of the transmission has to be turned clockwise to get it free since it has left-hand threads. Before loosening the nut, check for bent sheetmetal lock tabs. Many have been left out all together over the years.
6. The clutch basket is held to the clutch hub by a plastic retainer ring that's kept in place over the fingers by little C-clips. These need to come off before they can be separated.
7. After removing the crank nut, the crank pulley should come off easily along with the stock chain and the clutch basket.
8. The clutch hub can be a bit stubborn to come off the mainshaft since it is tapered with a woodruff key. Rivera Primo has a simple tool that shocks the hub off the mainshaft saving lots of sweating and possibly damaging the bike or yourself. Notice the mainshaft bearing support already on the transmission. You'll need to order one from Rivera Primo if you are switching from closed to open primary.