BIKES YOU’VE NEVER SEEN BEFORE: 1972 YANKEE 460MX SINGLE

The worn paint on the gas tank happened back in 1972 when Barry Higgins did the test riding on the Yankee 460MX. This  bike was at the 2024 Las Vegas Mecums Motorcycle Auction. It was bid up to $27,000, but the owner didn’t take the offer.

Yankee, who gambled on the big, twin-cylinder, six-speed, Yankee 500Z, was owned by John Taylor, who was both the American Bultaco and Ossa importer. John had a dream to build the ultimate American off-road bike. To achieve this, he talked Ossa into modifying a twin-cylinder, 460cc, Ossa road race engine, designed by Eduardo Giro, into a 488cc dirt bike engine by mating two 250cc Ossa Pioneer top-ends, including the pistons, cylinders and heads, onto a unified two-cylinder engine case.

Dick Mann designed three frames for John Taylor. The first was the Ossa-powered Dick Mann Replica (DMR) short tracker, the second was the twin-cylinder Yankee 500Z and the final one was for the Yankee 460MX.

Dick Mann designed the large tubing frame on the 500Z. Dick had also built a dirt track frame for Ossa—which was marketed as the Dick Mann Replica (DMR). Less than 200 of these Ossa-powered flat trackers (bearing Dick’s name) were produced and when the 1971 Yankee 500Z began to languish in the sales department, John Taylor pinned his hopes on building a lighter, 460cc, single-cylinder motocross bike and had Dick Mann design a down-sized frame to house the smaller single-cylinder engine. The Yankee 460MX borrowed the Kelsey-Hayes rear disc brake from the 500Z, but used a front drum brake from a Husqvarna. The Dick Mann influence showed in the large-diameter tubing, double-cradle frame with its oval section swingarm.

The 460cc Motosacoche engine was a very clean design with nice castings, plentiful finning and a twin spark ignition. This restored  prototype has a Bing carb instead of the original IRZ carb.

Surprisingly, even though John Taylor was the Ossa/Bultaco importer, he went to Switzerland to spec a 460cc, air-cooled, piston-port, two-stroke Motosacoche engine. The Motosacoche engine was incredibly modern for its time, especially when compared to the Ossa powerplants. The Swiss engine had many modern features including a twin spark ignition with two plugs (with the second plug’s timing retarded for a fuller fuel burn). Carburetion was via a 36mm, double needle, IRZ carburetor. All in all, Yankee Motor Corporation only had eight of the radially finned engines on hand during prototype testing.

Barry Higgins was the test rider, but there were only two Yankee 460MX prototypes built. If one-of-only-0two sounds good to you, the 1972 Yankee 460 MX should whet your appetite, Sadly, the two completed prototype Yankee 460MXs were the only Yankee motocross bikes built by the Yankee Motor Company of Schenectady, New York. Too bad, because it was a beautiful machine and could have been a success if given more time.

You might also like

Comments are closed.