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VOL. 55 ISSUE 47 NOVEMBER 27, 2018 P107 "Later on, there were two distinctly different paths we took [with the engine build] to compli- ment the riders' different styles. Randy Goss had a different style from Jay [Springsteen] altogether. Randy liked the piston port engine where it had more peak power, but a narrower range. And he used a wider split between fourth and fifth [gear]. Jay used an engine with a little less peak power, but a wider [powerband] range. [For Jay's] we grafted a Yamaha reed block onto the cylinder and used a narrower split between fourth and fifth, so when he shifted the rpm would be less of a differential, but it had the wider powerband. Randy typically was a pole-putter and Jay was a high-liner. Those particular engines complimented both their styles." Even though the short-track bike was raced so little, a great amount of development and modification went into the machines. To this day Werner recalls some of the details of what they did to optimize the MX- 250 engine for flat track racing. "We converted them from Dell'Orto carbs to Mikuni. We made special air boots for the air filters… it was like a steel airbox rather than just clamping an air filter on. Designing the pipes had a lot to do with the power delivery. And like most factory racing teams, Harley-Davidson's squad spent a lot of time studying the AMA rulebook and optimizing, shall we say, engine design sometimes based on what wasn't specified in the book, rather than what was. "One of the, what you might call, sketchy way of doing it had to do with the rules indicating that you had to use a production-based cylinder head, but you could modify it any way you wanted. Our production cylinder heads didn't have a lot of fins. Some of the top fins were cut off for the overhead up-pipe. That reduced the amount of fin area. An aftermarket company made a great radial fin head, but you couldn't use it because it was an aftermarket head. But the rulebook said you could modify the stock head any way you wanted, so we took a Gilar- doni head and bored it out and then took the stock head and essentially screwed the sparkplug section into the Gilardoni head. That was our modification," Werner laughs. "So about two-square inches of it was stock Harley head and the rest of it was Gilardoni. "It raised a bunch of eyebrows, but we did it within the rules. It just helped keep them a little cooler." By '77 the bugs were worked out. In front of 38,365 fans in Houston, Springsteen passed Steve More- head on the first lap and led the rest of the 25-lap main. A rule change for 1977 restricted short-track entries to 250cc single-cylinder machines (it had previously allowed up to 360cc engines and 250cc two-stroke multi-cylinder machines). The new rules caused a flood of new entries at Houston, perhaps the most diverse in any AMA Grand National race. Ossa, Suzuki, Cara- bela, Montesa, Can-Am, Bultaco, Yamaha, KTM, Penton and Harley could all be seen on the 131-rider entry list that night. Five different engine brands were listed in the top 10 in qualifying with Hank Scott the fastest on a Shell Thuett Yamaha and Springsteen second. Springer ended up on the pole after winning the fastest of the six heat races. Behind winner Springsteen it was Ted Boody, who held off Kenny Roberts in a thrilling heat race, mov- ing up to finish second, giving fac- tory Harley a 1-2 finish. Mike Kidd took third on a Penton-powered machine set up in a KR chassis. It was a miracle for Kidd who was bat- tling a severe case of stomach flu. Springer would win it again in 1981 and '82 with essentially the same bike, with a few differences, including a later move to a Cham- pion frame. In 1984, the short-track rules changed again, allowing 500cc four-stokes singles, rendering the Aermacchi 250cc two-strokes un- competitive. The two-stroke era was largely over, and over quickly. At the '84 Houston Short Track National only one two-stroke qualified for the main—Terry Poovey, on, ironically, a Honda 250cc two-stroke. Randy Goss won on a Harley-Davidson certified Rotax-built 500cc four- stroke single. The little Harley-Davidson two- stroke short-track machines may go down in history as the most man hours re-engineering for the fewest number of races entered for just about any racing motorcycle ever built. CN Subscribe to nearly 50 years of Cycle News Archive issues: www.CycleNews.com/Archives