We spotted Michael Boogerd (Rabobank) and Markus Fothen (Gerolsteiner) testing this carbon version of the Dura-Ace crankset at the Tour de France, and were met with the inevitable tight lipped response from Shimano. Now, on the first day of Eurobike, Shimano have officially launched the new Dura-Ace crankset FC-7800C.
Surprisingly, the crankset actually hides an alloy core. The alloy frame provides the structural rigidity; the interlaced and wrapped carbon keeps the weight down. The reason Shimano haven’t gone down a complete carbon route is that they constantly found that although weight decreases with the use of carbon, so does the rigidity.
The halfway house certainly hasn’t had a detrimental effect to the weight. Analysing the numbers, Shimano are claiming 709g for the complete crankset including the bottom bracket. SRAM’s recently launched RED crankset tips the scales at a claimed 780g (including bottom bracket). We’ll be looking very closely at Campagnolo to see how they compare.
The Dura-Ace FC-7800C (we assume the C refers to the carbon) runs on the current Hollowtech II platform and uses identical bottom bracket cups and bearings as the current alloy Dura-Ace crankset.
The crankset will be available in 53/39T and 52/39T gear combinations with 170, 172.5 and 175mm crank arm lengths. Look for availability in Spring 2008.