This is one of those motorcycles where information is frustratingly scant.
I think it’s based on a post-War Triumph, maybe a TR5 Trophy with the 498cc OHV four-stroke twin. (It has an Amal 276 carb.) [See comments. —Ed.] The bike was built by an underground Kyoto workshop called Kamikaze Chop, and it was wheeled out at the Joints custom show the other day. Visiting US luminary Jeff Decker selected it as his pick of the show; can anyone supply more information about this beautiful machine?