News & Analysis
The fastest little pushrod motorcycle in the world
Morris Marshall
8/26/2009 6:22 PM EDT
A Chinese-made Dayun motorcycle recently set a speed record for its class--150-cc motorcycles with production pushrod engines--on the Bonneville Salt Flats. The two-way average speed was 61.77 mph. But wait a minute! Isn't that something like setting a speed record for the world's fastest rubber band-powered automobile? Where's the relevance?
The fastest speed attained by the Dayun motorcycle in tests, using a carburetor, was about 55 mph. The new speed record was established using fuel injection and ignition timing controlled by an electronic engine control unit (ECU) designed by ElectroJet, a Brighton, Mich., company and based on an MCU supplied by Freescale Semiconductor.
That's an improvement of more than 12 percent, a dramatic example of what can be done with electronic controls on a small gasoline engine.
Most people do not associate small gasoline engines with huge numbers or with air pollution, but hundreds of millions of lawn mowers, snow blowers, chain saws, leaf vacuums and other small, gasoline-engine-powered devices are emitting high levels of carbon monoxide, hydrocarbons and nitrogen oxides.
For example, a typical push lawnmower, according to the EPA, emits as much hourly pollution as 11 cars. To combat this, the EPA is implementing new rules to cut hydrocarbon and nitrogen oxide emissions from small gasoline engines. Similar rules are being implemented in other developed countries.
Closed-loop electronic ignition and fuel injection controls are an absolute necessity for meeting the new rules at an acceptable cost.
That's only the beginning. As auto-centric as we are in the U.S., we forget that most of the rest of the word does not travel by car. The Third World travels on two wheels, on scooters, mopeds or motorcycles which are popular even in other developed countries. Those vehicles are produced in huge volumes with little or pollution control. Worldwide motorcycle production is approaching 50 million units annually, with more than 75 percent of that production coming from China, India and Indonesia.
They may not be Gold Wings or Harleys--passenger cars on two wheels--but in the Third World, 150-cc scooters, mopeds and motorcycles are basic transportation. They're prime markets for ECUs.
Over the last three decades the semiconductor industry has made a major contribution to improving automobile performance while cutting air pollution. But there's more to do. The same thing needs to happen for all the small gasoline engines providing recreation and convenience, and for all the two-wheeled and small four-wheeled vehicles providing basic transportation. Semiconductors also can help improve performance, increase fuel economy and decrease pollution in those applications.
A little motorcycle buzzing across the Bonneville Salt Flats may have shown the way.
Morry Marshall is vice president of strategic technologies at Semico Research Corp.




AlexKovnat
9/1/2009 7:49 AM EDT
Congratulations Dayun on your magnificent technical achievement. As a Michigan resident, I'm pleased that ElectroJet of Brighton played a role in that record-setting run at Bonneville.
But now that motorcycles are under the gun regarding emissions, what about safety? Will 150 cc motorcycles and scooters be subjected to ever more draconian safety as well as emissions regulations?
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Work to Ride, RIde to Work
9/1/2009 10:12 AM EDT
Fuel injection is already used on a number of high end motocross bikes. Those are relatively small engines albeit pumping out 50+ h.p. But this stuff isn't really new. It's just certain industries trying to increase the market size (oh, right I meant to help the environment.)
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drkepley
9/15/2009 1:52 PM EDT
If you would like to see fuel injection performance, check out the Harley VROD (VRSC)which features Electronic Sequential Port Fuel Injection (ESPFI). Oh yeah, it has been around for years.
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mambocougar
9/21/2009 5:21 AM EDT
About power boost:
a) motor was riding at 61+mph up from 55mph
b) air force to overcome is proportional to *square* of speed
then:
power increase shall be sth like 26% not 12%
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