It’s no secret to anyone who rides with me. I have used the Dura ace Di2 system for the last 2+ seasons and love it! Shimano has finally released the Ultegra version of the Di2 group for the consumer market and it will be a huge hit for them. You will get all the performance of the Dura ace version for 30% less money. Advances such as plug in play are used in the Ultegra version that I would expect to see in the next revision of Dura ace, both groups share the same battery and charging system but that will be it as far as cross compatibility of the shifting components.
In the initial production only the drop bar shifters will be available but in the mid Summer 2012 I will expect to see the other shifters become available. These will include the climbing shifter, sprinter shifter and bar end shifters. These options will be a huge bonus for anyone who wants to have multiple shifters. This advantage will become apparent when aero bars are used, right now this is a compromise set up in this area. The hills make it so that a dedicated shifter on the end of the aero bars can be a hassle to shift when climbing and a drop bar shifter makes you break the aero position that aero bars give you on a regular basis. Anyone who can only operate the bike with one hand or has limited hand strength should really see this option as a improvement. The programmable buttons on Ultegra make this even better. Now both buttons can have the same function.
Below is Shimano’s specs for the group. Figure about $2500 without pedals. The install can be challenging if you haven’t worked with the group at first but those challenges are easy to overcome.
Shimano HOLLOWTECH II crankset with integrated bottom bracket for lightweight design and excellent rigidity. This allows the cyclist’s muscle strength to be converted into forward motion as effectively as possible.
The cut-out chainrings provide added weight savings and rigidity.
Tooth design and shift ramps on the inside of the large chainring enable even easier and smoother shifting from one chainring to the next.
A compact version is also available especially for mountainous terrain.
chainring sets: 52T–39T or 53T–39T
compact chainring set: 50T–34T
crank arm length: 160 / 165 / 170 / 172.5 / 175 mm
weight: 790 g (53–39T) / 788 g (50–34T)
both 170 mm in length inc. bottom bracket
The rear derailleur is pre-programmed allowing you to shift gear quickly and accurately in all conditions. The derailleur is immune to rough circumstances and protected from impact damage by its reinforced inner cage. It has a maximum sprocket of 28T for wide-range gearing.
Programmed electronic shifting – fast and accurate
Never drops out of alignment
Crash saver function
Inner cage impact protection – cage moves automatically inwards on impact
Max. rear sprocket: 28T for wide-range gearing
Weight: 270 g
Rapid gear shifting is achievable using components that have been designed to be used with one another. The cassette is an important element in the drivetrain. This is why the sprocket design has been optimized to allow you to get the most out of the Di2 system.
weight: 209 g (11-23)
Anyone who has experienced Shimano`s mechanical, ergonomic STI levers knows just how much control they have over all components.
With Di2 technology, shifting is even easier and more precise – just a light touch, as soft as a mouse click, is sufficient for the front or rear derailleur to instantaneously select the correct gear. Shimano riders will be used to them immediately since all the buttons are in the same place as on regular levers.
The distance between the lever and the handlebar is adjustable. This makes it extremely easy to brake and shift even for riders with smaller hands.
ULTEGRA Di2 ST 6770
DUAL CONTROL LEVER
lightweight levers for optimal comfort and control
digital push button shifting – like clicking a mouse
ergonomically designed hood shape
lever reach adjustment – fits all hand sizes
weight: 313 g (pair)
The front derailleur’s operation is pioneering. Smooth shifting is guaranteed thanks to a microchip communication link with the gear levers.
What’s more, shifting the rear derailleur automatically trims the front derailleur. This ensures that the chain never rubs.
Its rigid construction guarantees swift, silent, smooth shifting even under the most demanding of conditions.
ULTEGRA Di2 FD 6770
fast, accurate, smooth shifting
programmed, automatic trim – silent shifting
weight: 162 g
The battery forms the Di2′s heart. Its lithium ion technology guarantees a range of at least 2,000 km [1,250 miles] after which it can be fully recharged in just ninety minutes.
The battery’s status can be read from an indicator next to the handlebars so that you’ll never be confronted with any unpleasant surprises. Derailleurs can also be reset or trimmed from this control unit.
ULTEGRA Di2 SM BTR1
high-performance lithium ion battery (7.4 V)
easy to assemble/dismantle
charging time: 90 minutes
weight: 71 g
Exceptionally powerful, adjustable and controlled application. Braking is now even more powerful and faster thanks to a modified cable inlet.
In conjunction with STI levers, these brakes provide the ultimate in stopping power. Improved compound brake shoes have improved braking in wet conditions by 100%.
A light touch of the brakes going into a bend or a full-on emergency stop… either is possible thanks to the brakes’ controlled application.
interchangeable brake shoes
adjustable braking force
weight: 317 g
The forces exerted on a chain are incredibly large, yet its role is to provide smooth power transfer.
The chain has a unidirectional design to reduce chain suck and improve shifting performance.
This chain features perforated plates that help to reduce the weight to 267 grams.
weight: 272 g (116 links)
To complete the system, opt for Ultegra SPD-SL pedals.
These are available with extra-wide platforms for better power transfer. The bearings used are maintenance-free and their wear-resistant top surface makes them exceptionally durable. Their aluminium spindles make them incredibly lightweight too.
Two versions are available – aluminium and carbon.
The aluminium version weighs 314 g a pair while the Ultegra pedals with a carbon composite body reduce the weight to 265 g a pair.
adjustable spring resistance
weight: 314 g / 265 g