This is a very clean street tracker, built by Bob Netherton, and it isn’t until you take a closer look that you realize what a nice job he did here. Twin carbs on the right, exhaust on the left, it looks perfect. Bob was a big fan of bikes sliding sideways around dirt tracks, but it wasn’t until he saw the work of Mert Lawwill that he figured he might be able to build one of his own that captured the right look. As Bob says below, he managed to talk Mert into selling him a few parts and he went to work. This is no ordinary Sportster conversion, it’s a C&J frame, Buell forks, Lawwill/STD heads, Penske shock and … well, I’ll let Bob tell the story.
Back in the ‘70’s I became a huge fan of dirt track racing. I was in awe of those guys who could ride around a 1/2 mile fairgrounds oval, feet up and sliding sideways at 90 mph! The one machine that has dominated this all-American sport for decades is the Harley Davidson XR 750. Lean, mean, and just plain elegant, the beautiful lines of this rare beast have inspired many to dream of a street-legal version that captured the spirit of the original. In 1983, Harley Davidson rolled out the XR 1000 Sportster, which was the closest Milwaukee would ever get to a road-going XR racer. The bike was expensive, suffered from poor suspension and had major engine problems. The model never caught on, and production stopped in 1984.
In 2005, Mert Lawwill (former Grand National champion) produced a limited number of XR replicas, built on a factory new Sportster. His bikes featured dual carbs on the right, dual high exhaust on the left, and did a pretty good job of capturing the look of the original. About 30 examples were built before production was stopped. When I saw Mert’s street tracker, my interest was stoked and my longtime dream of building my own street tracker was rekindled.
I soon talked Mert into selling me a set of cylinder heads, cams, and exhaust pipes; and my project was underway! A donor 1998 Sportster engine was obtained and completely rebuilt with new 1200cc components. The Lawwill/STD performance cylinder heads increase compression ratio and flow. The custom Andrews cams accommodate the reversed intake/exhaust configuration of the rear head. The custom Supertrapp dual exhaust system is all stainless steel with adjustable baffles for tuning. 38mm Mikuni carburetors mate to custom intake manifolds, and a Crane HI-4 ignition system is utilized.
The frame was fabricated by C&J who has supplied DT frames to Harley’s racing department. The chrome-moly dirt track frame was custom built to accept the modified Sportster engine, features a fully adjustable side-mounted Penske DT shock, and contains 3 qts. of oil for the engine.
The fully adjustable front forks are from a Buell S-1 and are mounted in custom CNC-machined drop-down billet triple clamps. Custom CNC-machined billet hubs are laced to 19” Sun DT rims with Maxxis DT tires. Brakes are from Performance Machine and mate with the EBC rotors via custom caliper carriers. Hand controls are also from Performance Machine and are mounted on Flanders DT bars mounted in custom riser blocks.
The electrical system components are from Wire Plus. The custom front number plate houses a halogen headlight and turn signal LED strips, while the custom tail light contains two 48-LED clusters that burn light red for running lights, bright red for brakes, and blink yellow for turns.
Storz supplied the hand-made aluminum gas tank, the fiberglass seat pan with Saddleman pad, and the rearset gearshift mechanism. Paint and hand-lettered graphics are by Wild Wes Paintworks.
This is definitely one of the nicer builds I’ve seen recently and I have a hunch Bob is pretty pleased with how it turned out. I like it.