Giro d'Italia - Stage 18 - Moena to Ortisei/St. Ulrich
The lowdown: Yes, the new Dura-Ace is lighter, yes it has another cog, yes it’s more expensive, yes it’s more powerful, efficient, (insert other positive adjective here). But is it better than 7900? Yes.
While thousands of fans lined the streets around L.A. Live for the final stage of the Amgen Tour of California, eager to see some of the sport’s biggest names, a small group of tech reporters avoided the day’s proceedings altogether. Instead, we gathered at a golf course clubhouse in Los Angeles’ Griffith Park.
We didn’t sport polo shirts and we weren’t meeting for a tee time. We were there to see the future. Or Shimano Incorporated’s version of it.
Shimano has come a long way from its beginnings in the early 1920s. From its first product, a single-speed freewheel, Shimano will now offer road cassettes with an additional 10 cogs. That’s right, Shimano has confirmed it. Eleven-speed is on the way.
The 9000 mechanical series of Dura-Ace will be the first Shimano group to receive the extra cog, with availability starting in September 2012. The electronic 9070 Di2 will follow in December. But there’s a lot more than an extra cog when it comes to the new Dura-Ace. Shimano 9000 is a complete redesign.
There’s a lot of material to cover here, so let’s start with an overview. As stated above, both of the new Dura-Ace groups will be 11-speed and because of that, the groups will only be compatible with Shimano’s new wheels and some existing Mavic wheels (used without any spacers). So if you want the latest, it’s going to cost you.
How much? Well, the 9000 mechanical group will run $2,700. The 9070 Di2 group will lighten your wallet to the tune of $4,140.
There are a few other things that stick out. The crank now only has four spider arms. The wheels are now wide-rim affairs, the mechanical shifters are slimmer than ever. Weights have gone down as well, even with an extra cog. The mechanical group weighs in at 1,977 grams, while the Di2 version is only slightly heavier at 2,047 grams (including the internal battery and wiring). That’s a weight savings over 7900 of 77 grams for mechanical and 172 grams for Di2. Both of these weights include cables, something not all manufacturers quote when giving weights.
Cranks: one crank, period
The most obvious change to the group is the lack of a fifth arm on the crank spider. The look is a bit bizarre at first, but after hearing the engineering reason behind the four-arm design, I like the cranks more.
There are dead spots in every pedal stroke. That’s no surprise to anyone, but Shimano decided that there was no need to build a crank that was stiff during that period of the revolution. Shimano’s super stiff, hollow chainrings allowed the removal of the fifth spider arm without reducing pedaling efficiency. The new crank also drops 52 grams from the 7900 crank.
Interestingly, Shimano has also done away with standard and compact versions for the new crank. Only one crank is offered and it’s essentially a 110mm bcd (compact) with a 24mm spindle. Obviously you must use Shimano’s new rings because of the unique spacing of the four-arm, 110mm spider. But again, thanks to the extremely stiff chainrings, Shimano will offer the crank with 50-34, 52-36, 52-38, 53-39, 54-42, and 55-42 gearing options. There will be no need to buy another crank if you decide to tackle the Dolomites for your next vacation, or take on a super fast time trial amidst your normal time scaling mountainous roads. That said, Shimano rings aren’t cheap. So choose wisely!