Cycle News

VOL. 55 ISSUE 46 NOVEMBER 20, 2018 P101 The Formula 750 BMWs were then raced in the Daytona 200 in 1973 by Pridmore and Liebmann. There's no question Daytona, with its long straights and high-banked turns, was not an ideal circuit for the BMW against massive horsepower of the 750cc two-stroke F-750 machines. To give you an idea of the speed dis- advantage Liebmann and Pridmore faced, Paul Smart won the pole for the 200 that year on a Suzuki TR750 with an average speed of 101.871 mph. Liebmann and Pridmore quali- fied 74th and 75th, respectively, both at an average speed of just over 91 mph. Pridmore dropped out relatively early, while Liebmann finished the race four laps behind winner Yama- ha's Jarno Saarinen. The tight and twisty Loudon, New Hampshire circuit was much better suited to the strengths of the BMW and Liebmann finished a respect- able 13th, Pridmore 18th. Pridmore then gave the BMW F-750 racer its best finish of the season with an 11th- place at Pocono. That would ultimately prove to be the best AMA Grand National result for the Butler & Smith F-750 ma- chine, although Liebmann, Pridmore and Justus Taylor won numerous club races on the bikes. The team continued to refine the bike and it improved over the next couple of seasons, but by now the Japanese two-strokes got better by leaps and bounds and had pretty much chased out nearly all of the four-stroke entries. The BMW F-750 race bikes reached a peak of development in the project's final season, 1975. The bikes were now revving to a stunning 10,500 rpm, producing 86 horse- power and capable of 165 mph. They were likely one of the most powerful pushrod twin motorcycles ever raced in AMA competition. That year, Pridmore was pleasantly surprised to find that his machine was able to out-accelerate even the mighty Yamaha TZ700s up the hill coming out of turn one at Road Atlanta, "As long as the TZs weren't revved up to peak," he added. In order to produce that kind of power out of the mild-mannered R75 powerplant, Gietl was pushing the engine to its limits. "These were 50-mile motors," Gietl grinned. "You're not going to run an endurance race with these things. And you'd better rebuild them before the next race because the wear rate was quite high. The amount of flexing in the motor was pretty serious." Perhaps the biggest development of the last version of the BMW was the implementation of Rob North frames, which took place late in 1974. It was at Pridmore's urging that the North frames were used. North had famously made excellent frames for factory Triumph and BSA Triples that finished 1-2-3 in the 1971 Daytona 200. The frames worked amazingly well. "Even with the cylinders sticking out, with the North frame, we could ride the bike to the edge of the tires without hitting anything," Pridmore recalls. "It was an excellent handling machine, maybe 340 pounds and it flicked side to side very nicely. At Daytona in '75, Pridmore was having an excellent run. "I was right around the top 10 fairly late in the race when the bike broke," he said. Also, in 1975, Gary Fisher was recruited to race one of the B&S BMWs with a prototype monoshock and showed amazing speed at Laguna Seca. Gietl claims Fisher started from the front row in his heat race and battled with the factory Ya- maha of Kenny Roberts in the early going (Note: There is no reporting in Cycle News or any of the magazines that covered the race to support that claim, but I'll take Udo's word for it.) At Laguna the monoshock broke, taking Fisher out of the race. Fisher's best result was 16th in the two-leg Ontario road race national at the end of the '75 season. Fisher's Ontario finish marked the end of the BMW F-750 project. By then Butler & Smith was shifting focus to the up-and-coming AMA Superbike class and the excellent BMW R90S. Pridmore would win the 1976 AMA Superbike Championship on the Butler & Smith BMW R90S. The North-framed BMW F-750 bikes still survive according to Gietl. One he says is at the Barber Museum and another at Irv Seaver BMW in Orange, California. Gietl feels the F-750 BMW gave them the knowledge to put them at the top of the superbike class in the early years. "We learned so much from that Formula 750 bike that translated over," Gietl said. "We put a lot of time and effort into that F-750 bike and we were proud of what we were able to get from the machine, but by then it was a lost cause with the domination of the two-strokes." Lost cause or not, the Butler & Smith Formula 750 machine was a motorcycle that began to change the staid image of BMW and its lasting legacy was helping to produce a championship-winning Superbike. CN Subscribe to nearly 50 years of Cycle News Archive issues: www.CycleNews.com/Archives

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