Motorcycle specifications SundanceSuper XR-TC Trans-am 2022 A Tourer with a Japanese silversmithing twist

In Tokyo’s Setagaya district, a man named Zak Shibasaki is redefining the laws of mechanics and the American-style hot rod. His masterpiece? The Sundance Super XR-TC Trans-am. A machine that doesn’t just roar—it sings a high-precision melody.

The genius of Setagaya

To understand the Trans-am, you must first understand the philosophy of Sundance Enterprises. Here, they don’t “customize”; they refine. For decades, Shibasaki-san has been tracking down the endemic weaknesses of Milwaukee engines to transform them into race engines capable of crossing a continent without batting an eye. The Trans-Am is the culmination of this quest: the marriage of the Twin Cam’s torque and the legendary agility of the XR750.

A 2-liter heart: the XR-TC fusion

The name isn’t just a marketing gimmick. XR-TC refers to the grafting of XR-style cylinder heads onto a Twin Cam lower block. But make no mistake—few parts still come from American foundries.

The “robohead” engine features cylinder heads entirely machined by Sundance. Their design allows for optimized airflow that the original engineers would never have dared to imagine. The result? Power exceeding 150 hp at the rear wheel, where the stock Harley engine struggled to produce even half that.

The engine uses extra-long connecting rods and a 100% dynamically balanced crankshaft. The goal is simple: to eliminate unwanted vibrations and retain only the “noble” pulses of the V-twin.

“This isn’t a bike that vibrates; it’s a bike that breathes.” — A saying that makes perfect sense once you’re in the saddle.

The art of intake: the “Big Boy”

One of the most fascinating elements on the spec sheet is the Sundance-Keihin FCR “Big Boy” carburetor. In an era of sterile electronic fuel injection, Sundance stands its ground with a flat-slot and oval-venturi system. This piece of engineering delivers throttle response of unprecedented ferocity while maintaining millimeter-precise linearity. It is the direct link between the rider’s wrist and the explosion in the combustion chamber.

Handling: the Trans-Am lives up to its name

While the beast is capable of dragster-level performance, it was designed for the road—the real one. By replacing steel with aerospace-grade aluminum and titanium, Sundance brings the weight down below 290 kg. For a touring bike, that’s spectacular.

No cheap suspension. It features Öhlins components reworked in-house to offer real comfort on the highway and a precision never seen before on winding roads. The billet-machined calipers provide a bite that the bike’s weight never seems to compromise.

The Sundance Super XR-TC Trans-am isn’t a bike for everyone. It’s aimed at those for whom mechanical perfection is a religion. It’s a paradoxical machine: more American than the original in character, and Japanese in its precision.

M.B.i - Manufacturer photos