Ilmor, the U.K.-based engineering firm that works with NASCAR, F1, and MotoGP racers, has brought out a new engine technology.
Motorcycle racing fans are used to classic two-strokers tearing up the track, and four-stroke engines are now the norm. But the new motor from Ilmor is a five-stroke.
According to Visordown, the three-cylinder 700cc engine puts out about 130bhp. That’s nothing to get excited about, but its torque numbers – 120 ft/lb of torque at 5000 rpm – are impressive indeed. It’s also supposed to be much more fuel-efficient than current technology.
The engine’s secret lies in two camshafts, a high-pressure unit that turns at half the speed of the crank, and low-pressure camshaft that turns at the same speed as the crank.
The high-pressure cam works with two outer cylinders on the engine, similar to a modern four-stroke. Exhaust is collected in a central cylinder from the outer cylinders, where the low-pressure cam extracts more energy, from the added expansion process.
Because your fuel is doing more work, the bike is in turn more fuel-efficient. The other added benefits of this technology include a compact size, and a reduced compression ratio, that can be used to delay the onset of engine knock.
Even though this is a new gasoline engine design, it wouldn’t require any new material or manufacturing innovations to put it into production. It’s more likely to be held back by racing bodies that ban turbochargers.
cool stuff. nice idea.
hmm … very interesting …