IRVINE, CA (BRAIN)—Shimano Ultegra 6700 is entirely new for 2010 and borrows the look and many features of the Dura Ace 7900 series to drop 150 grams of weight compared to Ultegra 6600.
The most noticeable change is the redesigned crankset that borrows Dura Ace technology for its hollow large chainring to keep things light and stiff for crisp shifting. The look is also clearly Dura Ace inspired. The new crank saves 15 grams over the current Ultegra SL crank.
And like Dura Ace, ST-6700 Dual Control Levers feature hidden cables so everything is under the tape. The levers have carbon blades, are more compact than previous Ultegra levers, now have reach adjustment and easier braking from the hoods.
ST-6700 levers are backwards compatible with 6600 series Ultegra drivetrains and brakes, though Shimano says mixing the groups will not take full advantage of the new features. The front derailleur stroke of the new group is similar to the 6600 front derailleur, but the brakes have revised pivots like Dura Ace.
Derailleurs all adopt wider pivots for less flex and the group uses an asymmetrical chain similar to Dura Ace.
Brakes have revised pivots similar to Dura Ace groups, but because the front derailleur stroke remains similar to 6600 Ultegra, backward compatibility is possible.
Rounding out the new group is the WH-6700 Ultegra wheelset, which weighs 1650 grams and is Road Tubeless compatible.