This 1971 Bultaco Pursang Mk. 4 is one of several examples of the Spanish brand’s handiwork when it comes to building competitive motocross machines, and Tom White has beautifully restored copies of all the significant Bultacos in his Early Years of Motocross Museum. Many of them enjoyed far more on-track success and higher sales than the Mk. 4.

So why is this particular model so near and dear to White? Because he rode a similar scrambles model with support from Bultaco in America through his Novice professional year in AMA flat track in 1972. The Pursang Mk. 4 was sold in two versions, a scrambles model with a 19-inch front wheel, universal tires, and clip-on handlebars, and the motocross model shown here with a 21-inch front wheel, knobby tires and MX-style crossbar handlebar.

White also says that the Mk. 4, with its sleek fiberglass bodywork is the best-looking Bultaco dirtbike ever produced, and its useable torque and stout top-end power made it easy and fun to ride. It was a tough customer in motocross, and its long wheelbase, fork angle and low center of gravity also made it hard to beat in flat track competition even as Bultaco’s legendary Astro flat-track models were joining the model lineup.