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Fastest shifting possible plus fuel economy gains

Dual clutch transmission systems have been increasingly adopted by automobile manufacturers as a way to increase performance and fuel efficiency at the same time. DCT is a semi-automatic transmission with two separate clutches for odd and even gears. One clutch drives the odd numbered gears, while the another clutch drives the even numbered gears. This setup eliminates the torque converter used in traditional automatic transmissions and allows a computer to shift more smoothly and quickly than is humanly possible. However, the option for manual shifting is still available, and many companies have paired DCT systems with paddle-shifters.

Volkswagen already has DCT available in the Jetta, Passat, Golf, Rabbit, and Touran, while the Audi A3, S4, and TT have it available as well. Ricardo makes a seven-speed DCT for the 1001 horsepower Bugatti Veyron, and Porsche is replacing its Tiptronic transmission entirely with its DCT system named PDK.

VW, Audi, Bentley, Bugatti, Lamborghini, SEAT, Skoda, and Scania are all part of the Volkswagen Group, ranked as the third largest auto maker in the world. Porsche is set to join their ranks in 2011 as part of a merger agreement. Collectively, the VW Group is the largest adopter of DCT systems and is looking to make DCT an option across their entire product range.

Ford and Mazda are also planning to get in on the DCT action. Ford is branding their version of DCT under their PowerShift label, and will start using it in the Focus and Fiesta. Mazda is planning something similar across their entire product line by 2015.

Honda is starting small with their entry into the DCT market. The company has shown off the world's first DCT system for motorcycles, and will introduce it in large displacement sport bikes next year with the 2010 VFR1200F. Honda claims that they have come up with a light, compact design that allows it to be combined with existing engines without substantial layout modifications.

Traditional dual-clutch transmissions tend to be too bulky for motorcycle use, so Honda's system is designed to be extremely compact. The new system employs original technologies such as dual input shafts, exclusive in-line clutch design, and concentration of hydraulic circuitry beneath the engine cover to achieve a compact design. Compactness and low weight is further enhanced through the use of a simple shift mechanism design based on that of a conventional motorcycle shift drum.

In order to respond to rider demands in a broad range of situations, the transmission is equipped with three operating modes. There are two fully automatic 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 claims that optimized shift scheduling achieves fuel economy equal to or better than that of a fully manual transmission, enabling their DCT to deliver both sporty riding and environmental performance combined.

The VFR1200F also features anti-lock brakes (ABS) as standard equipment, as well as a dual combined braking system (CBS) shown in previous generation VFR motorcycles.

The new transmission has 100 patents pending, and is claimed to provide "sporty riding enjoyment with easy operation". Honda intends to gradually expand the deployment of the new DCT system to more of its large displacement motorcycles over the next few years, focusing particularly on sport models destined for use in developed countries.

Honda CEO Takeo Fukui stated in May that Honda was working on a new system that could be matched with future hybrids. The Honda Fit already has a paddle-shifter option, and the company has already announced that production of the Honda Fit Hybrid would begin before the end of 2010.

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