2012 Shimano Dura Ace 7900 10 speed Group
2012 Shimano 7900 Dura Ace 10 speed Group
Shimano lowers the overall weight and shave 135 grams off the Dura Ace 7800 group. The weight savings comes off the following components: Dual Control Levers (-40g), crankset (-15g), chain (-18g), cassette (-10g) and brake calipers (30g/pair). This is only the tip of the 7900 technological iceberg. Here's a summary of the lineup.
Shimano adds a compact crankset with eight different cassette ratios from which to choose (11-21, 11-23, 11-25, 11-27, 11-28, 12-23, 12-25,12-27). The Dura Ace 7900 crankset and chainrings have an increase in stiffness by 20% compared to 7800 crankset. This improves shifting performance and power transfer. Shimano reduced the rear derailleur shifting stroke by 20%. Additionally, you no longer have to trim the front derailleur making front shifting faster. Shimano's Dual Control shifters have reach adjustment, and the shift housing is now hidden beneath the bar tape. The Dura Ace brakes get a 20% dry power boost. The wet braking performance is doubled. Shimano Dura Ace 7900 is for cyclists ready for some serious riding. 2012 Dura Ace 7900 group includes Crankset, Dual Control Levers