Dura-Ace crankset FC-7800C

Shimano carbon crankset compatible with new Dura-Ace

At the Eurobike show in August 2007 Shimano introduced a carbon fiber Dura-Ace crankset FC-7800C. Originally this crankset was designed to be compatible with the Dura-Ace 7800 series. However, with the introduction of the new Dura-Ace 7900 series this year they decided to change this. Shimano will deliver this crankset to be compatible with the new 7900 group instead.

Additionally, they will be able to provide a special chain ring set to make this crankset also compatible with Dura-Ace 7800.

As announced recently, the new Dura-Ace 7900 has a further refined front shifting performance and trimming of the big chain ring is no longer needed. These features were made possible by a new chain ring design and new front derailleur of Dura-Ace 7900.

FC-7800C has an aluminum core to realize a lightweight yet very rigid construction. By using this technology, Shimano developed a crankset that combines the best of both materials. The aluminum frame ensures a stiff set-up for optimal power transfer while using carbon saves weight. Weight of this crankset (including bottom bracket) is 715 grams.

This state-of-the-art crankset will be available in gear combinations 53/39T and 52/39T in crank arm lengths 170, 172.5 and 175mm.

Available as after market product from end of December 2008!

Shimano Dura Ace 7900 - 2009

All cyclist interested in their components have been waiting eagerly for new information about the Shimano lineup for 2009, after several prototypes have already been spotted in the pro peloton since the spring. Many rumors occured about the technical specifications and new features, but many were - obviously - especially interested in the new optics of the premium group from the guys based in Osaka.

Since several weeks we already had the answers to those questions up our sleeves, but were not allowed to show them. Now we can finally share the pictures, which were taken during an official product presentation some while ago, enjoy:

RD-7900 (Rear derailleur with carbon cage)

FC-7900 (standard crankset 53/39)

FC-7950 (compact crankset 50/34)

ST-7900 (STI lever)

BR-7900 (rearbrake)

The electronic Version 7970 will be presented in a couple of weeks. Further technical information and high resolution pictures of the several components will be published with the official press release. For sure, you will find it here on light-bikes.de .

Press Release from Shimano North America:
Shimano introduces the all new 7900 series Dura-Ace. The new mechanical Dura-Ace group loses over 135g while maintaining it’s legendary durability and improving performance and ergonomics.

Since 1973, Shimano’s Dura-Ace components have been at the forefront of pro racing and pro-level technology. Dura-Ace has continued its legacy of being proven in the peloton as well as serving as a launch pad for new technologies. Index shifting (SIS), integrated brake and shift levers (STI), and hollow forged cranks (Hollowtech II) have set Shimano’s Dura-Ace as the benchmark in road bike componentry.
FC-7900 Dura-Ace Crankset

The iconic Hollowtech II hollow forged crank has always been a benchmark for strength to weight performance characteristics and is the perfect platform for a crank intended to be used at the highest echelon of competition. Combined with a hollow outer chainring the crankset is 20% stiffer for optimal power transfer while still saving 15 grams. Other changes include redesigned chainring teeth for better contact and power transfer. Improved bottom bracket seals further reduce contamination and friction.

New for 2009, Shimano will also carry a Dura-Ace level compact crankset.


ST-7900 Dura-Ace Dual Control Levers


The new STI Dual Control levers offer a refined ergonomic shape while reducing the weight by over 40 grams. With a Shimano first, the new STI levers offer unidirectional carbon fiber lever blades which reduce weight and offer shift cables hidden under the handlebar tape for a more sleek design. Using a revised internal mechanism along with PTFE lined casing, the shifting is still as light as ever.

Shifting stroke for the rear derailleur has been reduced by 20% for quicker shifts and a built in reach adjuster allows for fine tuning the fit for riders with smaller hands.

The shifters continue to have integrated controls for the all new FlightDeck computer (SC-7900), which has been updated to include heart rate, altitude, grade, cadence, gear position, and directly downloadable data via a wireless connection. The new SC-7900 is completely wireless.

CN-7900 Dura-Ace Chain

The new asymmetric design of the Dura-Ace chain has redesigned plates that improve the contact interface with the cogs and reduce the chance for chain suck on the chainrings. Other improvements to the links provide greater durability and life with less noise and smoother function. The chain uses hollow pins and weight drops by over 18 grams even with the addition of a quick connection / removal link. A departure from the traditional Hyperglide connection pin, the SM-CN79 quicklink provides a reusable connection and removal point for the chain. The quicklink can be used on any Shimano 10-speed chain and the new chain can also be joined by a traditional Hyperglide 10-speed connection pin if necessary.
RD-7900 Dura-Ace Rear Derailleur

With a new carbon fiber rear pulley cage, the rear derailleur loses another 16 grams while maintaining durability and improving performance. The new design is compatible with wider range cogsets and can accommodate a maximum 28 tooth cog. The available wider range creates even better compatibility with compact cranksets.
FD-7900 Dura-Ace Front Derailleur


The new Dura-Ace front derailleur cage eliminates the need to manually trim the front shifting. Additionally, the redesigned, more efficient wide linkage and optimized spring tension combine for reduced shifting effort.
BR-7900 Dura-Ace Brakes
Increased linear response, improved braking power, and reduced weight all make their way into the latest version of the Dura-Ace brakes. A new brake pad compound doubles wet condition performance, while also improving dry power by 20%. Enhanced linear response comes from a redesigned caliper arch while a lower profile cable stop creates better lines for the cables and reduces cable friction. While other brakes ditch sensible features like a spring tension adjuster or adjustable toe, the new Dura-Ace brakes still come equipped with those features and manage to drop nearly 30 grams per pair.
FH-7900 / HB-7900 Dura-Ace Freehub and Front Hub


Both the hub and freehub body have evolved to designs that improve rigidity for efficient power transfer and quick handling. The bearings have been updated with a new tool-free bearing adjuster for quick bearing adjustments. The freehub continues with the durable titanium shell and quick engagement internals.
CS-7900 Dura-Ace Cassette

Shifting has been even further improved by creating an even more rigid (and lighter) aluminum carrier unit along with re-engineered teeth profile. Cassette design is lighter as Shimano has developed a super lightweight and rigid aluminum cassette sprocket carrier. The largest four cogs are titanium and weight is reduced by 10 grams. Available combinations will be: 11-21T, 11-23T, 11-25T, 11-27T, 11-28T, 12-23T, 12-25T, 12-27T.

True to tradition, Dura-Ace 7900 combines new technologies with features relevant to the highest levels of competition.
Available Fall 2008



Interchangeability: DURA ACE (7800 series) and new DURA-ACE (7900 series).

Press Release from Shimano Europe:
New DURA-ACE: “Evolution of Perfection”

Shimano is introducing the new DURA-ACE 7900 series that sets a new benchmark in top-level road racing components. Shimano has combined all of its engineering resources with the latest technology to realize an increased level of perfection that will benefit professional riders as well as road racing enthusiasts. Besides offering a further improved performance and an attractive design, the weight is reduced significantly.

Crankset
The seventh generation DURA-ACE group introduces revolutionary technology into the road racing scene. Highlight is the HOLLOWTECH II crankset that combines an attractive aerodynamic design with remarkable weight saving and completely new engineering features.
This high tech beauty is developed out of thin walled, hollow forged aluminum and features some novelties in road racing technology. The outer chainring for example is hollow which saves weight and makes it 20% stiffer at the same time for an optimal power transfer.

There is a wide choice of FC-7900 chainring combinations: 53/42T, 52-39T, 53/39T, 54/42T, 55/42T and 56/44T. Crank arm lengths: 165 – 180mm with 2,5mm steps. Also a DURA-ACE compact crankset FC-7950 is available with a 50/34T chainring combination. The chainring teeth have been redesigned for an improved chain contact to improve power transfer. Furthermore, the bottom bracket features improved sealing for smoother rotation and longer durability.

This crankset weighs 725 grams including bottom bracket. This is 15 grams lighter than the current DURA-ACE crankset FC-7800. Rigidity remains the same.

Dual Control Levers
The new Dual Control Levers show the importance of state-of-the-art technology with regard to performance enhancing design. The lever blades are made of multiple carbon layers, finished with a unidirectional carbon fiber top layer with a special coating. This advanced technology ensures the best performance in terms of rigidity, durability and lightweight design.
Shift cables are hidden under the handlebar tape without sacrificing performance. This was made possible by the development of a new internal mechanism in combination with new PTFE coated inner cables.
The Dual Control Levers have a reach adjustment mechanism that will better accommodate smaller hands and a wider assortment of bar bends. Furthermore, the shift lever has a 20% shorter stroke for faster shifting. The hoods have an ergonomic design for increased comfort, even at long distance rides.

The shifters feature integrated buttons on top of the hoods to operate the new wireless FLIGHTDECK computer without the need to take the hands of the handlebar. FLIGHTDECK measures data such as heart rate, altitude, inclination, cadence, gear position and more. It works with coded wireless signals that prevent interference from other electronic units. The new FLIGHTDECK computer can be used to make a wireless connection with a PC to analyse riding data (software is included). The Dual Control Levers are over 40 grams lighter than the current version at 378 grams per pair.
Besides Dual Control Levers, also new bar end shifters and down tube shifters will be available to match the new DURA-ACE. A carbon brake lever BL-TT79 for aero handlebars will be available for time trial and triathlon usage.

Chain
The new DURA-ACE chain CN-7900 carries a lot of innovative technology. It has an asymmetric design and features redesigned outer plates to reduce the chance of chain suck. Also the inner plates have been redesigned for an improved contact with the cassette sprockets. The result is smoother shifting even under high load, for example when climbing or sprinting. Furthermore the chain runs smoother and is more silent than its predecessors and the new design allows a higher durability as well.
CN-7900 can be mounted with a reusable quicklink SM-CN79 that can be (dis)connected without using any tools. This quicklink is compatible with the other Shimano 10-speed chains as well. Also a normal connecting pin can be used. The chain has been developed with hollow pins and perforated inner plates to make it lighter. Weight of this chain is 252 grams, which is almost 30 grams lighter than the current version.

Derailleurs
The rear derailleur has a wide gear ratio and can be used with sprockets of maximum 28 teeth. It is compatible with the use of a compact crankset without the need for a medium cage derailleur. It has a full carbon pulley plate and a carbon/resin composite P-body that helps to reduce the weight to 166 grams.

The front derailleur has a lightweight design and an optimum spring tension for feather light downshifting. Trimming the outer chainring is no longer needed to allow a better concentration on the ride. The efficiency has been improved by using a stiffer and solid wide link design. Weight is only 67 grams.

Brakes
The brakes feature new compound brake shoes that doubles the brake performance in wet circumstances and improves stopping power in dry weather by 20%. These new brake shoes feature a longer durability as well.
The brakes have been developed with an enhanced brake arch proportion for an increased linear response. A lower cable stopper ensures a better cable routing and reduced cable friction. The Dual-Pivot caliper brakes feature also a spring tension adjuster and adjustable toe-in brake shoes The dual pivot bolt and center bolt as well as the inner cable fixing bolts are made of titanium for an optimised lightweight design of 293 grams per set.

Cassette/Hub/Freehub
Shimano has developed a super lightweight yet very rigid aluminum cassette sprocket carrier. Also the separate sprockets have been redesigned for more robust shifting performance and to save weight. This 10-speed HYPERGLIDE cassette will be available in a wider variation of combinations: 11-21T, 11-23T, 11-25T, 11-27T, 11-28T, 12-23T, 12-25T, 12-27T. The four biggest sprockets are made of titanium. Weight is 163 grams (11-23T).

The hub and freehub have an increased rigidity that improves rotation even when the quick release is tightened strongly. Furthermore, they have been developed with a completely new bearing adjustment system that enables easy manual adjustment without the use of a cone wrench.

This DURA-ACE group is the ultimate combination of state-of-the-art technology, lightweight design and innovative appearance. It sets a new standard in road racing technology, in which details are nowadays more important than ever. More info at http://www.dura-ace.com

Availability in the market: October 2008.