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These might include some form of auto. The Phase Two motor would be running and mounted in a chassis for Sepang tests in October - refined and slightly more compact than the first motor, "to make it fit into the chassis better," according to management spokesman Fricker. Speculation links Sauber Petronas with Team Roberts, currently running their home-built KR3 three-cylinder two-stroke with backing from car manufacturer Proton. Apart from the obvious Malaysian link, Petronas owns 20 percent of Proton. Did this mean that the obvious connection would be made, with the new triple being run out of Banbury? Not necessarily, according to a Petronas spokesman. "In terms of sponsorship, Petronas and Proton are completely separate." SPE spokesman Fricker confirmed that they had been speaking to a number of teams and a major manufacturer, as well as to Dorna and IRTA, but details were confidential. "We will make an announcement at the launch of the machine at the Malaysian GP," he said. Proton Team KR manager Chuck Aksland also poured cold water on the assumption. "Nothing is finalized yet, but the way it is looking now we will be running our two-stroke next year," he said. But he admitted they had had talks with SPE, among other people, and did not rule out a future connection with the team. Placed in the heart of England's famous F1 belt, they were ideally placed to operate as chassis constructors and team operators, in the case of an F1-style scenario coming to prevail in bike GP racing, he said. Fricker refused to confirm or deny that Harris has built test chassis for the October tests, but added: "Who is building the machines is not significant at this stage. We need a chassis in order to continue our engine testing program." eN (Far left) Osamu Goto poses with his 16,000 rpm, 200-horsepower triple. (Left) A single nozzle feeds each variable-length intake trumphet on the Sauber. (Below) Goto holds one of the engine's connecting rods. The SPE motor was criticized for its bulk when first shown at Suzuka at the first race of the season. It was displayed again alongside a V4 Swissauto 500cc two-stroke, with its exhausts fitted. Now it no longer looks so large. The two-stroke exhausts are not heavy, but they need to be there within a certain distance of the exhaust ports for the engine to operate, said Goto, and in the end the two-stroke occupied more physical space than the SPE four-stroke. 6 . VIBRATION, FUEL CDNSUMPTIDN AND "COS-'"'T'I'" Vibration was also an important consideration, with production a possibility for the Petronas-Sauber motor. With a balance shaft and 120degree crankshaft timing, giving equally spaced firing strokes, the triple was as smooth as any of the designs. In fuel consumption, the twins were the most economical, the fours the greediest, the triple well placed in between. Costwise, the Vfour was the most expensive, the triple slightly more expensive to construct that a V -twin. At the end of this exercise, adding up the relative scores, the triple proved on aggregate to be the best solution, said Guerciotti. Other details of the design followed - one key innovation being the forward-facing intakes, with the three-into-one exhaust. Asked why they had not included a five-cylinder engine, like that planned by Honda, in the exercise, Goto (an ex-HRC senior employee) intimated that he had been surprised by the choice, since it did not match any obvious criteria. "You have to take into account hat Honda have marketing reasons for this choice. They will probably sell a V-five road machine," he said. "Our aim was to build an effective racing engine, with the possibility of going into production in the future," added Fricker. Formula One technology will prevail in the new four-stroke class adapted to take the smaller budgets into account, said Goto. "Within three years, all the machines will be using fly-by-wire throttle controls," he insisted. Sophisticated control programs can be tuned to suit to preferences of individual riders, dialing in as much or as little wheelspin as they prefer. This potential had been planned for the SPE engine from the start. The SPE triple, with four valves per cylinder, uses pneumatic valve springs - where compressed air performs the function of a steel valve spring, as in F 1 car engines. "This is not necessary for an engine that need rev only to 15,000 rpm, but we included it with a view to future development with higher revs," said Goto. "The technology is very well developed and reliable in F1, and will not require an air-pump." Leakage was so small that a compressed air bottle could keep the system topped up for race distance, he said. "The only disadvantage comes in initial manufacturing cost." Fuel injection is by a single nozzle per cylinder, with variable-length intake trumpets. Current racing fourstroke technology uses standing waves and harmonic pulse effects on the inlet in much the same way as a two-stroke does with its exhaust. There are unconfirmed reports that the Series 2 PSE engine will actually lean back in the frame, to give more space to the crucial airbox and induction tract geometry of the forwardintake engine. The quantity of power simply isn't an issue. F1 engines currently make 270-odd hp per liter, while current thinking is that 200bhp would be as much as the motorcycle chassis, tires and rider could handle. "Our ta rget of 200 horsepower was very easily achieved," said Goto which allows them to use engine management programs to manipulate the character of the power, to give a broader power spread and a more usable engine. "Our engine development at the moment is not to seek power, but to win the race," said Goto. They expected a 370-mile life between rebuilds, and that a one-rider team would require some 30 engines over a season, averaging at about two per race. The cost implications are frightening - until Goto explains that in this context a "new engine" is really just a rebuilt engine. "Crankshafts would usually go a full season, as with a F1 engine. Camshafts would also be re-used. Replacement items are as usual pistons and bearings." Other F1 technology is evident in the very over-square dimensions. Asked if bore and stroke were indeed 93mm by 47.5, as with the car engin-e, Goto smiled, and said: "It's a rumor." How about automatic gearboxes as run in F1? "In fact, they use motorcycle-type gearboxes, with permanent-mesh gears and engagement by dogs," said Paul Fricker. "We plan to start with a conventional gearbox, but to leave room in the design for improvements as required to be competitive." 0: U 0: I • n e _ lIS • OCTOBER 10,2001 41