Global automotive supplier Denso Corporation has developed a new electronic fuel injection system for small motorcycles called DIET-FI (Denso Intelligent Economical Technology-Fuel Injection). The company says DIET-FI is the world’s first fuel injection system that doesn’t use a throttle position sensor or engine temperature sensor. Instead, it uses newly developed control technologies that ensure the same fuel economy and environmental performance as conventional fuel injection systems, thus cutting costs.

Usually, fuel injection systems are only used in motorcycles, but in recent years there has been a growing need to apply these systems to smaller motorised bikes up to 150cc that are used in emerging markets, like China. To cater to this demand, Denso says its new low-cost fuel injection system delivers similar fuel economy and environmental performance as conventional systems but with fewer components.

DIET-FI has five fewer components than conventional systems. Employing extensive research, the supplier developed control technologies that were able to eliminate the throttle position sensor, intake air temperature sensor, engine temperature sensor and ISC idle speed control step motor. Specific compensation technologies include a temperature estimation control that integrates a thermistor into an electronic control unit and a fuel metering control to determine acceleration/deceleration using an intake air pipe pressure sensor.

DIET-FI is currently manufactured by Gongcheng Denso (Chongqing) Co, a group company that manufactures motorcycle components and supplied to Wuyang-Honda Motors (Guangzhou) Co.