In view of environmental concerns, Honda is also promoting the installation of 4-stroke engines for motorcycles in order to reduce fuel consumption and exhaust gas emissions. Along with plans to expand the use of PGM-FI, Honda has set new targets for exhaust gas emissions reduction and fuel efficiency: by 2005 the company is determined to reduce total hydrocarbon emissions to 1/3 the 1995 level, and to improve fuel efficiency by as much as 30% for all Honda motorcycles sold worldwide.

PGM-FI Prototype Model (100 cc 4-stroke engine)

Compared with a carburetor, PGM-FI provides optimized air-fuel mixture control at all engine revs, thereby further improving combustion conditions. This results in the promotion of a cleaner-running engine with improved fuel efficiency and power output characteristics, as well as better starting performance. However, since motorcycle engines demand delicate accelerator control, fuel injection systems for motorcycles require exacting precision manufacturing technology for structural parts, as well as highly accurate electronic control. Owing to the extra development and manufacturing costs of these technologies, Honda has so far only introduced fuel injection systems into its bigger motorcycles. Honda now intends to further develop PGM-FI technology in order to extend its application to more of its smaller motorcycles at a reasonable cost.

Honda has made environmental protection a priority, and in 1992 announced its intentions in this area with the release of "Honda Environment Statement". Further, based on "Honda's Plans Concerning Environmental Remediation", published in 1993, the company has been striving to develop measures in the motorcycle field to combat air pollution and help prevent global warming.