Honda’s efforts to reduce emissions and improve fuel economy go beyond its motor vehicles – they also stretch to its motorcycles, with the company developing new 700cc and 125cc engines with an accompanying second-generation Dual Clutch Transmission.
The 700cc engine is a liquid cooled, four-stroke, in-line two-cylinder engine that is part of the mid-class range. Its fuel economy achieves an approximate 40 per cent improvement compared to other sports models in its class.
During the development of the engine, Honda outlined a number of objectives including that it should be easy to handle with plentiful torque; that it should offer top class, fuel efficient environmental performance; and that it should have a lightweight design to allow more freedom in the body layout.
Among the features of the new engine is a wide variety of low friction technologies that boost fuel economy. It has an optimised combustion chamber shape and optimum valve timing while resin coating is applied to the pistons and lightweight aluminium material is employed for the first time in a motorcycle in the friction-reducing roller rocker arm.
The accompanying dual clutch transmission has a learning function added to each selected running mode that can detect a variety of riding environments from city streets to mountain passes. It delivers fuel economy on a par with manual transmissions.
As for the 125cc engine, it has been developed for next-generation 125cc scooters and includes an advanced idle stop system. Fuel economy is around 25 per cent better than that of conventional engines with the same displacement.
When developing the 125cc engine, Honda’s objectives focused on powerful output and greater durability; excellent fuel efficiency; and contribution to CO2 reduction; all at an affordable price.
