When we first saw images of this bike from Custom Works Zon, we assumed it was a restoration job. And it looked like builder Yuichi Yoshizawa would have to use all his legendary skills to get the knucklehead roadworthy again.
It turned out that we were wrong. This remarkable ?vintage racer? is actually a ground-up build: a client commission designed to evoke the spirit of classic V-twin competition machines, dents and all.

We?ve never tagged CW Zon as a retro-leaning shop, because most of their creations are sleek and highly?finished. But the best builders have a habit of throwing sudden curve balls, and so it is here. ?I imagined an old racer, and imagined how it would get dirty,? Yoshizawa-san explains. ?I enjoyed ?ageing? it.?
Virtually all the parts are custom-made. A mere handful aren?t, such as the steering neck, seat post and rear axle. Fans of classic V-twins will also clock the S&S KN93 engine?a well-engineered update of Harley?s original knuck motor.
It?s got generator-style crankcases, a capacity increase from 74 to 93ci, and a stump-pulling 83 lb-ft of torque, delivered at around 3,000 rpm.
Yoshizawa has kept the S&S ignition that these engines usually employ, but not the S&S Super E carburetor. Instead, he?s chosen an unusual twin-carb setup that looks terrific, but was extremely tricky to plumb in.

With the help of local specialist Flat Head Power, CW Zon modified the cylinder heads to accept a pair of Linkert M88 carbs. Usually found...