They don’t get any rarer than this 1969 Husqvarna. It’s the only one in the world, and it’s one of Tom White’s favorites.

As White tells it, the twin-cylinder 500cc project began when Swedish road racer Bo Grannath persuaded Husqvarna engineer Ruben Helmin to graft a pair Husqvarna’s 250cc cylinders onto a single case. The prototype engine was finished in 1968, but after testing it, factory motocross riders Rolf Tibblin and Torsten Hallman shied away from the 302-lb. machine, determining it to be too bulky and beastly for motocross. Even so, Husqvarna’s Gunnar Nilsson won the European FIM Motocross Cup on it in 1969.

Upon seeing its success, American Husqvarna importer Edison Dye felt that the engine could win the Baja 1000, so Husky rebuilt one of the roadrace engines to 492cc and shipped the machine over to Dye. In the hands of American team members Malcolm Smith, Carl Berggren, Gunnar Nilsson and J.N. Roberts, the Baja Twin lived up to its potential with a win in the 1969 Baja 1000. Dye then tried to convince the factory to build more of them so that he could sell them in the United States. Husqvarna declined.

Only 10 of the 500cc twin-cylinder engines were ever produced. Two were slated for roadracing and seven for sidecar racing, but this is the only off-road machine that ever existed. It languished in Dye’s San Diego warehouse for about 30 years before TwinAir filter company owner Frans Munsters bought the machine in 1998 and restored it to its former glory. White then obtained it, and today it sits in a prominent place in the Early Years of Motocross Museum for all to see. White has turned down offers of nearly $200,000 by other collectors wishing to purchase the bike.