We dig back in to our 2004 Sportster 1200 Custom project by slapping on a new belt and replacing the old rear sprocket with a shiny new Harley 6-Spoke Billet Sprocket, Chrome Hardware Kit and Sprocket Bolt Cover Kit.
Check out the difference between the weathered and worn, 10-year-old rear sprocket and the shiny 6-spoke Billet Sprocket from Harley-Davidson.
In order to replace the rear sprocket, the back wheel of our Sportster had to come off.
A busted belt threw a wrench into things. After work on our 2004 Harley
Sportster 1200 Custom project started so well, momentum came to a screeching halt after our 10-year-old belt snapped and flew about 25 feet from our bike when we dropped it into gear. Fortunately, we were in our driveway when it happened, so we didn’t get stuck like Chuck with no luck.
But the news wasn’t all bad. Our Sportster was in dire need of a new rear sprocket. The old one was faded, chipped, and generally looked like crap. To our good fortune, Harley-Davidson
stepped up to provide a new XL Slotted 6-spoke Billet Sprocket for the project (Part # 40418-04). Seeing how we needed to replace the belt as well, we slapped on the new sprocket and belt at the same time. To sweeten the deal even more, we got a new set of bolts for the 6-spoke Billet Sprocket in Harley’s Chrome Hardware Kit (#94708-98) and a rear sprocket bolt cover kit (#43876-04), too.
Swapping out the drive sprocket required the rear wheel to be removed. In order to replace the belt as well, the manual said the exhaust system had to come off, too. But because we’ve installed a set of Vance & Hines RSD Slant Exhaust
on our Sportster project bike already, we were able to cheat a little and only removed the bottom mounting bracket. After removing the bracket, we jacked up the rear to get the wheel off the ground. Taking the tire off required removing the spring clip, loosening the rear axle nut, and then loosening the drive belt adjusting nuts in order to slide the rear wheel forward a bit.
Before proceeding further, in order to change out the belt, the debris deflector, belt guard, and the drive sprocket cover all had to come off first, which is just a process of removing screws. The axle nut and washer were next, followed by the lower mounting bolts for the shock absorbers. We then used a rubber mallet to tap the rear axle to the right, holding onto the tire at the same time so it didn’t fall out abruptly. With a tug the big axle bolt came out and the back wheel dropped off. We had to jack the bike up a bit so it cleared the back fender and carefully slid the brake rotor out of the caliper. Finally, we pulled off the wheel spacer and were ready to swap out the sprocket.
The sprocket is attached to the back wheel via five bolts with washers. We replaced the old worn bolts with the shiny new Harley bolts and washers in the Chrome Hardware Kit. After giving them a dab of Loctite, we tightened them down to 55-65 lb-ft in a star pattern, starting with the lowest bolt. Installing the drive belt was as simple as sliding it onto the front and rear sprockets.
It was then time to put the back wheel back on. This is where it got a little challenging. The manual suggests putting a wooden spacer in the between the brake pads so the pistons won’t get pushed out if the brake lever is inadvertently squeezed, which we didn’t do. This made it more challenging trying to get the back wheel on because the piston had moved in a little. With a little finagling, we were able to get the rotor to slide back into the caliper. Another word to the wise. Pay attention to where the wheel spacers are so you can get everything back in the same order. The left side spacer is much thinner and smaller than the one for the right side. After cleaning and lubricating the axle shaft, it needs to be fed back through the swingarm, spacers, sprocket and wheel. We had troubles getting the spacers lined up just right while feeding the axle through at the same time, and it took two of us to get it just right.
After finally slipping the axle shaft through, we put the axle nut and washer back on, at this time only hand-tight, and then adjusted the tension on the drive belt. The axle nut was then tightened to 60-65 lb-ft and the spring pin was snapped back in place. The manual recommends replacing the spring pin when you pull the back tire off, but we were extra careful removing it and were able to reuse the stock pin.
After that, putting everything back on was just a reversal of the installation process. First the belt guard went back on, followed by the deflector. Next the shocks were bolted back on, as was the mounting bracket for the exhaust. Then we lowered the bike, checked the belt tension again, pumped the brakes to make sure they worked, and rolled the bike to make sure the wheel was lined up correctly.
Aesthetically, what a huge difference Harley’s Slotted 6-spoke Billet Sprocket makes. It now is one of the focal points of the bike’s right side. With the chipped and weathered sprocket gone, the new one conceals much of the haggard, worn wheel behind it. It is a handsomely crafted piece, and the chrome matches up to our rocker covers and the shiny covers of our Sportster 1200 Custom much better.
The new belt makes a noticeable difference, too. The old one was ten years old, so its teeth were worn and it had stretched a bit. Under hard acceleration, it would slip in lower gears. No more. Crack the throttle now and it simply hooks up and goes.
Looking good, running good, we’ve got plenty more to come, from the installation of a new Progressive Monotube Fork Kit to RSD Prostep Handlebars, risers, grips and levers to Harley Steel Braided Clutch and Brake Cables. Now we’ve just got to figure out what to do with that ragged old slotted disc we call a back wheel.