Date:07/05/2008 URL: http://www.thehindu.com/2008/05/07/stories/2008050758620300.htm

Kerala - Thiruvananthapuram

For the thrill of two-stroke biking

Staff Reporter

Engineering students have developed an electronic GDI system for motorcycle.

THIRUVANANTHAPURAM: Want to return to the heady days of throaty two-stroke bikes? Ever wondered how you are going to get engine power, low pollution levels and good mileage in one engine? Meet the team of final year students of the mechanical engineering programme at the Government Engineering College, Batron Hill, who promise to put the ‘vroom’ back in the life of every avid biker.

The team consisting of S. Abhinav Sivaraman, Mahesh Rao, M. Rajesh and Robin Gilbert claim to have developed an electronically-controlled gasoline direct injection (GDI) system in a two-stroke engine — something that two-wheeler manufacturers have only on their drawing boards.

The vehicle selected for this project was a 1998 model Kawasaki Bajaj with a 125 cc two-stroke engine. “The basic idea behind the implementation of this technology is to precisely time and quantify the amount of fuel supplied to the engine through a fuel injector by using an electronic control unit,” Mr. Sivaraman said. The unit calculates the amount of fuel to be injected by sensing the throttle position and the position of the piston.

An engine with a carburettor mixes fuel with air before the fuel enters the engine cylinder. This often results in wastage in the form of residual fuel through the exhaust pipe. With a GDI system the fuel is mixed with air only after it enters the engine. So, only the correct amount of fuel required would be consumed and the fuel consumed would undergo proper combustion. This, in turn would lead to a reduction in pollution and an increase in mileage, Mr. Sivaraman said.

The team estimated that by using their technology the pollution caused can be reduced by 50 per cent and the mileage enhanced by 15 per cent. The only ‘missing’ beat in this project that took three months and cost Rs.30,000 is that the combustion could be sustained only for about 20 to 25 seconds. “Sustaining combustion for this long is nothing as far as a commercial project is concerned. But our big achievement is that we demonstrated that direct injection technology is possible in a two-stroke engine,” Mr. Sivaraman said. The team members and their guide S. Remesh said by developing a better fuel pump, an injector and by installing oxygen and temperature sensors and better compressor their technology would find widespread commercial application.