Mule Motorcycles Super Street-Tracker - Special Feature

The XR1660 Punisher Street-Tracker.

Mule Motorcycles Super Street-Tracker - Special Feature

Mule Motorcycles Super Street-Tracker - Special Feature

Not very many custom bikes end up with a “development team.” But Mule Motorcycles’ XR1660 Street Tracker—named The Punisher by its owner—is not your average custom build.

First off, the man who commissioned the bike, Bruce Baxter, is a real rider who wanted to really ride this street-tracker. Second, he got Mule man Richard Pollock to build it, and nobody in the street-tracker biz has thrown more aerospace-grade fabrication, parts and plating at two wheels.

A key characteristic of this near-decade-long project was the fitting of 130 foot-pounds in a 40-foot-pound bag, so to speak. That is, the “Sportster” S&S cases got Axtell cylinders and dirt-track inspired dual-carb Baisley heads (one of two sets in the world). Those fancy heads and the fact that the engine displaces 100 cubic inches meant it was a significantly taller mill than what the C&J frame was designed to accept.

Fitting that engine in the frame was one of the many things that caused Pollock so much strife during the protracted build and development. “This bike stretched my imagination to the breaking point and beyond,” he said. “Every part, it seemed, was a design challenge all by itself. Many parts are the second or third version. It’s a prototype project that I thought would never end. There were times when I would get ‘fabricator’s block’ and my mind would go numb and blank for a month at a time. All brain space had been consumed. I didn’t even want to look at it!”

Pretty much everyone involved struggled to get through this one. As much as Pollock got beat up by the frame and other build issues, so was the engine taking its toll on Baxter and Dale Lineaweaver of Lineaweaver Racing. Job One was that Baxter wanted a 7500-rpm peak and the ability to sustain 6800 revs. That's slightly higher than typical with a Sporty mill, especially one displacing 100 cubes. You'll note a miles of oil plumbing in an effort to control crankcase breathing and lubrication. For a full rundown of the build, check out the September issue (on newsstands now, or buy instantly at www.zinio.com/cycleworld).

For visual candy shot by our own Brian Blades, also have a look at the gallery, and for sound and motion, watch the video. I got to ride the bike and have to say it was one of the most distinctly cool experiences I’ve had on two wheels. It was explosive, responsive edged and gave the suggestion that things would go wrong if you didn’t give it the respect it deserved. Think, well-trained wild animal… And you’ll see that Associate Editor Mark Cernicky had a good time in front of the video camera.