Honda VFR to feature world's first twin-clutch for bikes

Honda Motor Co., Ltd. today announced that it has developed the Dual Clutch Transmission, the world's firstfully automatic motorcycle dual-clutch transmission for large-displacement sport bikes.

The new transmission provides riders with a sporty riding experience, combined with easy operation and superior transmission efficiency, which delivers fuel economy equal to or better than a conventional manual transmission. The new VFR large-displacement sport bike equipped with the new transmission will be released in Europe and North America in 2010, with sales to commence in Japan at a later date.

This world's first motorcycle dual clutch transmission features a light, compact design that allows it to be combined with existing engines without substantial layout modification. Further, the new transmission delivers the precise acceleration control which riders require thanks to electronic control technology that helps ensure smooth, seamless gear changes. In order to respond to rider demands in a broad range of situations, the transmission is equipped with three operating modes, including two full-auto modes (D-mode for regular operation and S-mode for sporty riding); and a 6-speed manual mode, which delivers the same shift feel as a manual transmission. Honda intends to gradually expand the deployment of the new transmission to more and more of its large-displacement motorcycles, particularly sports models destined for use in traditional large motorcycle markets.

The new transmission features a dual clutch transmission configuration in which independent clutches are employed for the odd gears (1st, 3rd, 5th) and even gears (2nd, 4th, 6th), respectively. The two clutches operate alternately to effect gear changes. For example, when changing from 1st to 2nd gear, the computer detects the up-shift and engages 2nd gear, then releases the 1st-gear clutch while engaging the 2nd-gear clutch to achieve a seamless gear change. While some existing dual-clutch transmissions arebulky, the new system employs original technologies such as dual input shafts, an innovative in-line clutch design, and concentration of hydraulic circuitry beneath the engine cover to achieve a compact design. Compactness and lightness is further enhanced through the use of a simple shift mechanism design based on that of a conventional motorcycle shift drum. Optimised shift scheduling achieves fuel economy equal to or better than that of a fully manual transmission, enabling Dual Clutch Transmission to deliver both sporty riding and environmental performance combined.