Today's big news is the launch of a new version of Shimano's flagship Dura-Ace road groupset. But its electronic Di2 offshoothasn't been forgotten – an updated version is in development. It's yet to be officially launched but Shimano did give us some information on what to expect from the new 11-speed Dura-Ace Di2 9070 series.
There must have been a temptation just to adapt the original Di2 7970 to cope with the extra sprocket out back. Instead, Shimano have gone for a wholesale revamp. As their UK distributorsMadison put it: "They’ve proven it works, now they want to get it looking and working even better.”
As before, the electronic group shares mechanical Dura-Ace's crankset, chain, cassette and brakes. Elsewhere, there have been big changes though. The old wiring has been ditched in favour of the slimmer, modular, dual-core E-Tube configuration used on Ultegra Di2, and now Alfine Di2 too – apparently “the aim is to have a standard wiring system through all of Shimano’s Di2 groupsets”.
Dura-Ace Di2 9070 is looking good, even in prototype form
This means we now have the option to mix and match the groups, so expect some value-added options in complete bike specs next year. It also means it’ll no longer be necessary to heat-shrink the connections as with current Dura-Ace, as Di2 9070 will use the same waterproof connections as Ultegra.
The next big change is a new optional internal battery, available to fit either in the seatpost, seat tube or down tube. To get around any charging issues, a new junction box port will allow the battery to be charged in situ. As the internal battery doesn't require the same level of weatherproofing as the external version (though it's still fully sealed), it weighs 60 percent less.
The Dura-Ace Di2 9070 battery is designed to be housed inside the frame or seatpost
Shifter ergonomics have been improved, with an 8mm longer button and a new cable path on the brake lever, and the derailleurs are said to provide slicker shifting. They've also been significantly reduced in size and, more importantly, weight – as a pair they come in at 90g less than the current models.
The goal Shimano set out for the new Dura-Ace Di2, weight wise, was a 160g reduction overall, giving it parity with the mechanical group. The whole system weighed just 1,995g when we saw it in prototype form earlier this year – just 30g heavier than the mechanical version – and Shimano say the production transmission should still weigh sub-2,000g.
New for Dura-Ace 9070 is programmable multi-shift. This means that if you hold the button down, the rear derailleur will keep changing until it gets to the end of the cassette, reaches a pre-set (by you) number of shifts or you let go. This wrests back the major advantage of Campagnolo's EPS.
The Dura-Ace Di2 9070 derailleurs are said to be more compact, lighter and provide slicker shifting
"Tunability" is a buzzword Shimano kept returning to at the launch. The new Di2 can be customised to suit your needs, with the PC interface (sold separately) allowing you to configure everything from shifter operation – want to switch over the left and right shifting? Well now you can – to the speed at which multiple shifts are made.
Myriad secondary shifter options to tune your bike to your needs are also available, including sprinter triggers, time trial shifters, tri shifters and a new top mounted Roubaix shifter. No additional wiring is needed to add these, and there's no setup procedure either – the new junction box below the handlebar allows you to plug-and-play.
The under-stem junction box is the key to Di2 9070's versatility. It allows the addition of numerous 'plug & play' accessories
There are two versions of the box – SM-EW90-A, with three ports, and SM-EW90-F, with five ports – and combined with the three ports on the back of each STI lever, this offers a huge range of setup options.
The five-port box is also designed to work with Shimano's latest Flight Deck computer (SC-R770) via an ANT+ wireless connection. When used with mechanical Dura-Ace, the touch-screen computer shows what gear you're in and can be paired with ANT+ devices to show your speed, cadence and heart rate. It also offers remote operation via a bar end switch. Connect the Flight Deck to Di2 9070, however, and it comes into its own. You can use it to adjust your gears, show the battery level, perform simple system diagnostics and even programme the multi-shift function.
Shimano's latest Flight Deck computer can be used with both mechanical and electronic versions of Dura-Ace
Also in development is a time trial/triathlon-specific version of the new transmission called Dura-Ace Di2 9071. We'll bring you more on the new electronic groupset as soon as we get it.
What about when the batteries get flat during a ride? I know you are supposed to check to see if the battery light comes on charge it accordingly, but that is a bit of a concern.
Don't get me know wrong I have nothing against electronic gearing, its an amazing alternative.
It is impressive technology. Im waiting for when it hooks up to the cadence and heartrate and changes gears for you :)
Cant say I'll ever get to using it as a) I couldnt bring myself to pay $800 for a RD and b) I like to tinker myself and manual systems are better for that!
That's fair. Would you buy it if it had a storage dispenser which intravenously drip fed FUIC to your veins directly Matt? LOL
then I would be tempted!
Auto shifting is already out there by shimano.
Di2 is designed so that in the event of a flat battery the front mech stops shifting first. The rear continues to shift for another few hundred K to get you home.
i'm not sure about ultegra, but from my readings(with a vested interest in the matter) there hasnt been a single dura ace customer have to pay for a front or rear failure. the only failures ive read of, on various forums, are from CX use, with seemingly severe mud/grit damage. all those cases were warranty replaced/good public image replaced(i'm sure it wasnt a same day turn around though)
So the BikeRadar preview of DA 9000 hints that the chain pitch may have changed. Anyone know whether this is true? A changed chain pitch would be an utter disaster and result in massive incompatibility with all chainrings/jockey wheels/idlers currently on the market.
Chain pitch change has got to come. At present, the standard pitch is an imperial measurement, one of the few things still not moved to metric. My guess is that it will be twelve mm, rather than the 1/2 inch that is the current standard. I am surprised that it did not happen years ago.
Shimano did actually try a 10mm pitch for the track once I believe but gave up pretty quickly. While the metric system does make measurements cleaner and easier to understand, there's nothing wrong with keeping current 1/2" pitch chain. Chain width, sprocket width and spacing are all defined to 0.01mm anyway so there shouldn't be a problem in just saying it is a 12.7mm pitch chain.
I agree on the idea of keeping the current pitch, after all, it has been around for over a hundred years, but I fear that it will be a victim of the never ending search to reduce weight. Shorter pitch, narrower chain, slightly smaller diameter sprockets, there will be no end to it !