Regular readers will need no introduction to Richard Pollock. Better known as Mule, the irascible Californian is opinionated, blunt, and probably the best builder of tracker-style bikes in the world today.
Pollock is entitled to his opinions. If you were planning to write the textbook on how to create a high-performance street tracker, you?d save time by analyzing the components of (and thinking behind) a Mule build.

This silver dream machine is Mule?s latest creation, and powered by a hot-rodded Triumph T140 engine. Like many Mule bikes, it?s grounded in the present but with a nod to the past: the frame and swingarm are rare Panther items, crafted in British Columbia in the mid 1970s.
?The bike arrived?as so many do?with a list of simple, desired upgrades,? says Pollock. ?In the end, the only parts we retained from the donor were the swingarm and the main frame loop, both of which got multiple repairs.?
?The other request was a less than one-year turnaround. No!? Three years and an entirely new bike was the result.
Fine-tuning the frame was only the start of it. Pollock has installed a 1973 Triumph T140 engine, which puts out considerably more than the humble 54 hp it achieved in factory spec. The 750cc parallel twin has been built by Charlie Barnes of Branch-O?Keefe, one of the best performance engine builders in California.

As well as the usual internal magic, Barnes replaced the standard 30mm Amal carbs with 34mm Mikunis. For the other end, Pollock enlisted the...