Technique

Dura Ace and Electronic Dura Ace 2009

Details

Parent Category: Technique

Category: Shimano

Published on Thursday, 18 September 2008 11:41

Written by Luca Salvatelli

Shimano has whit no doubts presented one of the most interesting novelty at the level of components, in 2009. With the complete new group Dura Ace responded to attack by other company (Sram and Campagnolo) also pleasing his fans who have long demanded a new Dura Ace to improve the performance of the old group. The wait was rewarded not only with a Dura Ace entirely new but also with the introduction of electronic model, that has long run in trial on a bike of some professionals. Many of the latest news from this group:

Control levers: have been completely redesigned with a new ergonomics, more compact, and with the introduction of carbon brake levers, adjustable in the distance, and the straps fastening titanium. Reduced the trip lever for passage of the gear.

Rear derailleur: all new the rear derailleur with several components in carbon fibre. The new parallelogram to ensure greater accuracy changed. The new derailleur can use sprocket with 28 teeth and is compatible with traditional or compact cranks. It has a total capacity of 33 teeth. Front derailleur: even this component was revised in the quality of materials and geometry of construction. Now it is stronger and this gear provides steps faster and more accurate. Decreased, thanks to the best components and materials, including the weight.

Crank: the crank is all new, forged aluminium, to have maximum rigidity and the lowest possible weight. New crowns and the new type of attachment integrated ensures a better rigidity of chainring/cranks. It is available in a wide range of option: 53-42, 54-42, 53-39, 52-39, 55-52, 56-44, 50-34. Shimano has also presented a carbon fibre model, but for the same admission of Shimano, was conducted only because required by the market as Shimano believes that the best performance you reach with a structure alloy forged and not with fiber carbon. However, the crank carbon Dura Ace has an aluminium soul covered in carbon fiber. New also bearings bottom bracket, the more rigid; also available with the standard BB30.

Brakes: all the new braking system equipped with arms forged with greater strength and better linearity response to the command of the lever. The center bolt is in titanium. New possibility to regulate the voltage closing and opening of the body brake; redesigned the lever for the rapid opening of the body and new brake design of securing brake cable to reduce friction and improve the response to the command. New back cable, now has a more straight and this reduces the effort to drive and improves brake response to the command. New material friction, that allows better braking power on dry (20%) and especially in the wet (50%). Cassette sprockets: a new series of combinations and new profiles to facilitate the passage of the gear, these are the novelties. The combinations available are: 11-21, 11-23, 11-25, 11-27, 11-28, 12-23, 12-25, 12-27. The last four sprockets are in titanium.

Chain: The new chain con be mounted without tools and is thoroughly drilled in pins and meshes. Have differentiated profile on the inside and outside to improve the climb on the front gear and rear. Despite being lighter is more rigid than the old model. Di2: "Digital Integrated Intelligences", the new electronic gear Shimano.

Controls: commands follow those of Dura Ace normal but with the difference that the two levers of command derailleur gear and go to actuate the command that sends the impetus for the change of gear.

Rear derailleur: This follows the structure of the traditional one, but it can accommodate up to 27 pinions, with a capacity lower then.

Front derailleur: structure as the same as traditional individuality is not only to electro-assisted movement in the fact that the cage moves automatically according to the report back to avoid contact with the chain.

Battery pack is easily mountable under the bottle cage, has a long autonomy and a rapid charging. It is a period of charging enough to travel over 300km and a battery life than 20.000km.

Considerations

We have noted carefully the new group and we were able to taken a brief contact. About the group Dura Ace traditional we sea a realization really cared and the level of fame Dura Ace. The new command is well and being more compact facilitate those who have small or medium hands, perhaps those with large hands will prefer the old model. Despite the passage of cables inside the fluidity of action does not seem to have failed, although there seems greater than the old model. Reduced instead, the trip lever and improved the speed of passage of the report. All impressions that will be checked with a deeper test. For the electronic gear Di2 point out that the two levers are easy to operate even if we could have expected an effort to drive and a hike even less. Surely this is the preferred solution for avoiding unwanted gear passages. Strength drive and hike are lower than all current traditional competitors. Excellent functionality and implementation with a modest invasion of the whole. Excellent functionality derailleur that moves automatically to prevent interference with the chain. It remains the doubt about the battery life of 300 km are many for most users but not sufficient for randonnee. It remains a great innovation even though the overall level of no more than traditional Dura Ace, but he supports and can be a viable alternative.