Dura-Ace 7900 shifting – how does it perform?

There’s a lot riding on Shimano’s new Dura-Ace 7900 groupset, with the outgoing 7800 which it replaces being widely accepted as one of the best groupsets around. To find out how the new gear performs RCUK has been riding a Cervelo R3 equipped with the latest groupset and putting in some serious miles to answer one simple question: is it any good?

The shifters are the biggest area of change, with the cables now routed out of the back of the STI unit and hidden underneath the bar tape. They can be routed either in front of or behind the handlebars. The look is much cleaner and was a wise move by Shimano.

Ergonomics have also been improved. 7800 Dura-Ace featured a really tall knob at the front of the shifter body and Shimano have opted for a shorter shape with a much flatter mid-section. In practise it feels a much more comfortable place to place your hands both when in the saddle and during out of the saddle climbing. Some will no doubt miss the older shape but the new shape is an improvement.

The levers are shaped differently two, and now flare outwards more which is noticeable when on the drops, making it easier to reach the levers. Reach adjustment has been introduced which should make setting the levers up to suit easier. One of the big changes across the groupset is the introduction of carbon fibre, and the levers are now made from the black stuff.

Shift action is super smooth for both front and rear shifts, as we’ve come to expect from Shimano. One area of criticism however can be pointed at the amount of lever travel – there’s just way too much – encountered before the next gear engages something which SRAM’s Zero Loss technology on its RED groupset highlights dramatically. We’d like Shimano to address this for future groupsets.

While ergonomics have been greatly improved, the redesign isn’t without its drawbacks, and was highlighted when RCUK had to change the gear and brake cables on the test bike. Affixed to the front of the levers at the top is a small plate which must be popped off by the removal of a tiny screw (which had us going to the Tech dept. for a small enough screwdriver!) and only then can the cable nipple seat be accessed. Threading the cables through is a similarly fiddly process, and not something that should be attempted often. Surely Shimano could develop a better solution than this? There’s also more exposed internals underneath the lever body which could pose problems with dirt and mud finding their way in easily.

The new Ultegra shifters employ the same concept and will doubtless have the same good and bad points.

Along with the levers, the chainset is one of the more radical and eye-catching changes to the groupset. The outer chainring is now hollow which is said to allow an increase in stiffness but without any weight penalty. Chainring bolts now operate from the back of the chainset and threads through the inner chainring, spider and directly into the larger chainring, leaving a clean bolt-less front. Stiffness is certainly high when pushing the pedals, but with my legs it would be hard to detect a noticeable increase over 7800 in this area. The slicker shifting was easily noticeable though, with new ramps giving laser-quick up and down shifts each and every time.

Other changes of note include the lack of trim adjustment on the front derailleur, but happily due to wider plates there was no chain rub on any gear with a 53/39 11-23 setup so we can confirm trim adjustment isn’t missed. The dramatically restyled rear derailleur may be lighter and funkier looking, and now boasts a smattering of carbon bits, but shifts were just as smooth, slick and crisp as 7800 – which is no bad thing. In fact, shifting is just so light that I found myself looking down to see if a gear change had actually happened. Many people will criticise this quietness of gear shift but it is a joy to use a groupset that is so crisp and smooth.

Summary

More riding needs to be completed before a full review can be written, but at this stage in the test Shimano’s Dura-Ace is without doubt a significant step forward. There are no huge innovations (they’ve saved them all for Di2) but what changes have been made serve to make an already great groupset just a little bit better in all areas.

More at www.madison.co.uk and www.shimano.com