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Introducing direct injection technology into two stroke engines can greatly improve the exhaust emission and fuel efficiency. In this paper, we investigate LPG direct injection from the transfer port of a loop-scavenged two stroke engine. The injector nozzle is placed in an area where it can inject through the transfer port window directly into combustion chamber with minimal fuel spillage into the port and minimal loss of fuel to the exhaust port. Several portions and orientations are simulated to determine the best injector nozzle location and orientation. The simulation results indicate that high fuel trapping efficiency is possible with the proper location of the injector and injection timing. Experimental results show an 80% reduction in exhaust emissions with the transfer port mounted injector nozzle compared to the baseline carbureted engine.

Existing drive cycles do not correlate well with actual drive cycles in developing countries due to differences in vehicle mixes, and traffic flow patterns. Several distinct drive cycles were identified in Malaysia namely the urban, suburban, rural, highway and delivery drive cycles. Several methods were used in generating drive cycles including direct observation, motorcyclist surveys, vehicle shadowing with on-board wheel speed measurement and data logging. These drive cycles were compared to existing European, United States, world harmonized motorcycle drive cycles and evaluated for fuel consumption. Results indicate that the Malaysian drive cycles are capable predicting actual vehicle fuel mileage within +/− 10% for a wide range of vehicles, while the European drive cycle results in a 20%deviation from the actual vehicle fuel mileage.