Shimano introduce Synchro Shift + video

XTR mountain bike group goes electronic and allows control of both mechs with one lever. Will similar tech come to the road next?

by Mat Brett   May 30, 2014  

SC-M9050_STD_01-2

Shimano are introducing a new XTR mountain bike electronic groupset with a Synchro Shift function that allows one lever to control both mechs.

We usually confine ourselves to road cycling here on road.cc (the clue’s in the name), with a bit of cyclocross thrown in to add to the flavour, and don’t often touch mountain biking. We’re telling you about this new technology, though, because we wonder whether Shimano will transfer it over to their road groupsets soon.

The big news if you’re a mountain biker is that Shimano have announced the launch of their first electronic groupset for MTB, XTR Di2 (M9050). XTR is Shimano’s top-level mountain bike groupset, the MTB equivalent of Dura-Ace.

We won’t go into any detail on the electronicness of XTR because Di2 has been around in the road world since the 2009 product year, and the XTR version works on the same E-tube platform as the current road Di2 groupsets.

You’re probably already familiar with the concept, Shimano claiming, “The Di2 platform offers a number of advantages over a regular mechanical system including faster, more accurate and more powerful shifting which remains consistent in all riding conditions.”

The bit that we’re most interested in is Synchro Shift.

“With Synchro Shift enabled, it is possible to control both derailleurs with just one shifter,” say Shimano. “The front derailleur reads the position of the rear derailleur and automatically operates the front shift to position the gears in the most efficient gear and best chain line so the rider never has to worry about front shifting and correction shifts again. Synchro Shift… improves efficiency of shifting and riding.”

Essentially, you just decide whether you want to change up or down, and the Di2 system does the rest automatically. You don’t need to worry about the chainring/sprocket combination, that is all decided for you. If you want to go one gear harder and the most efficient way of achieving that is for you to be in a bigger chainring, the Di2 will move you there.

“Shimano have used all the data from test riding to produce two pre-set [Synchro Shift] shifting maps,” the brand says. “E-tube allows the rider to change these pre-sets and create their own preferred shifting map. While riding it is possible to change between the programmed shifting maps or change back to manual mode.”

Di2 is massively programmable and you don’t have to use Synchro Shift if you don’t want to. The XTR Di2 system has a digital display that indicates the battery level, gear position, shift mode (manual or Synchro) and suspension mode. You can change the shift mode using a button on the display.

Could Shimano transfer the Synchro Shift feature over to the road world? We don’t see why they wouldn’t, especially as it would be so easy to switch off if you didn’t want it.

Most road bikes use a double chainset (with two chainrings) rather than the triple you find on most mountain bikes (XTR Di2 will be in double and triple options), so you might argue that the Synchro Shift wouldn’t be as useful, but it could stop you from using the big sprocket while you’re in the big chainring – cross-chaining.

Imagine your bike is fitted with a 50/34-tooth chainset, for example, and an 11-25 cassette. Synchro Shift would never let you use the big (50-tooth) chainring and the biggest sprocket (the 25-tooth), for example, it would stop you from cross-chaining by putting you into the small chainring (34-tooth) and the 17-tooth sprocket. This would give you exactly the same gear as 50-25, but in a more efficient manner.

Are you wondering what happens if the Synchro Shift system moves the chain to another chainring when you’re not expecting it? You’re riding out of the saddle and want to change up a gear, and the Di2 brain decides the best way to do that involves moving you to a different chainring; how does that feel?

Well, we just don’t know because we’ve not used Synchro Shift yet – no one has outside of Shimano and their test riders. Shimano reckon that XTR Di2 has undergone over 20,000 test kilometres so presumably they’ve thought it all through and are happy with the results, but we have no experience to report.

Way back in 2000, by the way, Shimano bought the patents of former French component manufacturer EGS. One of those patents was for EGS’s Synchro Shift system for mountain bikes. This original Synchro Shift was a twist grip system with a righthand shifter that operated two cables, controlling both the front and the rear mechs.

“The front and rear derailleurs are highly synchronized,” said EGS. “Riders can concentrate on steering without worrying about the best gear to choose, as this is done ‘instinctively’ by the single shifter which selects the most suitable gear and at the same time ensures the best chain line.

“The sequential mode, like a gearbox of the same type, lets you run up and down through the gears, by clicking the shifter forward or backwards depending on the lay of the land. This gear shift technique makes it impossible to make a mistake by getting into the wrong gear.”

Obviously, Shimano’s electronic system bears little resemblance to the original Synchro Shift, but it’s a similar concept and it’s interesting that they’ve chosen to keep the same name.

The new Shimano XTR Di2 will be available from this autumn onwards (assuming it arrives on time). We don’t have prices yet.

18 user comments

Oldest firstNewest firstBest rated

Wow. This is so cool. If you can switch it 'on' and 'off' when you want how can you loose?

posted by Jacob [38 posts]
30th May 2014 - 16:23

17 Likes

Makes a lot of sense when you watch the video. I like the look of it. There's a good chance this is already being used by the top teams on the road as all it would need is a software update to do it

posted by Ssco [3 posts]
30th May 2014 - 16:33

12 Likes

I mentioned such an approach to shifting when it was identified that the SRAM wireless system only had 1 button on each lever. This it is more helpful for road than MTB, because often on the MTB want to drop a handful if gears at once (i.e. the front ring) in response to a sudden ramp - will be interesting to see how it copes with that.

posted by jug_23 [25 posts]
30th May 2014 - 16:57

14 Likes

Oh Dear! Another major innovation coming from the MTB side of cycling Devil although it is a logical extension of the Di2 system.

Like Jug_23 I am puzzled as to how it is going to cope with the gear dumps that are necessary in MTB riding. Thinking
Just to explain to non-MTB riders gear changing on the rear mech is single ratio changes up and multiple down. Front is single each way. Cool

This really is a possible game changer. I can see this being the default on all mid to high end road bikes in the next five years, if not sooner. Party

posted by levermonkey [368 posts]
30th May 2014 - 18:13

12 Likes

This seems to me such an obvious step from current Di2- I can't really understand why they didn't just program this into the system in the first place. What's the point of riding with a computer if it's not going to think for you? That wasn't meant facetiously, btw. It's very difficult to think of any reason why you wouldn't want this on a road bike, if you were spending the money for Di2.

posted by MNgraveur [34 posts]
30th May 2014 - 19:01

13 Likes

I would hope that you could program the shifters for that. For instance: You could use the right hand one for regular up/down and program the left hand one to drop you 3 ratios with the big button and 2 ratios with the little. Alternatively, you could program one button to dump three gears and another one to dump you all the way to your granny gearing from whatever you were in before. And so on...

posted by amullen [1 posts]
30th May 2014 - 19:25

14 Likes

Looks interesting, but plenty of mtb'ers are now ditiching multiple chain ring and the front mech and running a 1x 10 or 11 system using a clutch mech to keep the chain on. Obviously you cannot have the same range AND small jumps between the gears as a 2 x 10 or 3 x 10 for example, but it works for lots of people.

I think this synchro system is possibly better suited to the road though than MTB but who knows?

posted by domofarmfrites [19 posts]
30th May 2014 - 20:10

13 Likes

levermonkey wrote:
Oh Dear! Another major innovation coming from the MTB side of cycling Devil although it is a logical extension of the Di2 system.

Like Jug_23 I am puzzled as to how it is going to cope with the gear dumps that are necessary in MTB riding. Thinking
Just to explain to non-MTB riders gear changing on the rear mech is single ratio changes up and multiple down. Front is single each way. Cool

This really is a possible game changer. I can see this being the default on all mid to high end road bikes in the next five years, if not sooner. Party

Actually, latest version of XT shifters allow multiple shifts of rear mech in either direction. Slx will likely get that feature in next update as well (May have it already, can't recall) and my wife's flat bar road bike with tiagra shifters have same feature.

posted by joules1975 [69 posts]
30th May 2014 - 20:15

12 Likes

levermonkey wrote:
Like Jug_23 I am puzzled as to how it is going to cope with the gear dumps that are necessary in MTB riding. Thinking

I thought (could be wrong) that Di2 has gone the same way as Campag EPS in that holding a shift button down works through the gears until you release the button.

I agree that this would suit road better than MTB. Shimano were slow to adopt double chainsets and now seem to be slow adopting single ring drive trains.

Rob

posted by robert.brady [146 posts]
30th May 2014 - 22:39

10 Likes

Looks like a natural thing for a road system, as has been said one software update away from enabling this on all Di2 systems tomorrow - be interesting to see if this is only offered on high end systems first...

posted by bradtipp [11 posts]
30th May 2014 - 22:46

24 Likes

I have no idea what to think.

Cool. I get it. It will sell millions and become the default.

What an utterly marketing-lead 'innovation' no-one wanted or needed.

Let me check back on these predictions in 2 years.

I was told there would be Cake. Luckily there's http://TestValleyCC.org.uk

KiwiMike's picture

posted by KiwiMike [497 posts]
30th May 2014 - 22:48

13 Likes

Is the next innovation monitoring cadence and changing gear automatically?

posted by Carlosfoznango [6 posts]
31st May 2014 - 7:16

11 Likes

Carlosfoznango wrote:
Is the next innovation monitoring cadence and changing gear automatically?

I remember riding an 'autobike' about 15 years ago that did exactly that. I think it was Shimano.

I was told there would be Cake. Luckily there's http://TestValleyCC.org.uk

KiwiMike's picture

posted by KiwiMike [497 posts]
31st May 2014 - 7:27

11 Likes

It's possible that current road Di2 doesn't feature a big enough memory to hold the code required; bigger chip costs more so smaller margins.
Additionally, they may simply have kept it back to be able to launch a new product with a new 'breakthrough' feature. Standard marketing ploy, only drip the advances through to extend profitability. That and people often get nervous about too big a leap in development.
Looks fascinating, I'll be looking forward to seeing a road version reviewed.

posted by CharlesMagne [25 posts]
31st May 2014 - 9:09

10 Likes

I also test rode an automatic shifting bike way back then. Maybe Shimano has kept their Di2 stuff fairly conventional for a good reason. People like to have control after all.

Sequential shifting... how about this little project from 2010:
http://www.cyclingnews.com/features/fairwheel-bikes-creates-stunning-seq...

posted by kide [20 posts]
31st May 2014 - 10:53

6 Likes

In phase 2 this will be linked to power measurement and torque, but I reckoned (correctly) that we are going to get a drip feed of pre-planned 'upgrades' over the years to keep buyers coming in like Microsoft and Apple.

I just hope the shimano campag and SRAM don't end up competing on software features, as a bicycle should be mechanically led, you may eke a few seconds here and there by optimising shifts and ratio's, but where is the joy?

....yes I still ride 6 speed friction shift in summer, 8 speed in winter, sure,11 speed EPS would shift faster, more reliably and get me closer to the ideal ratio, but I'm still not going to win anything, and they look 'orrible.

All Campag

posted by Flying Scot [557 posts]
1st June 2014 - 12:02

12 Likes

posted by robert.brady [146 posts]
1st June 2014 - 23:01

4 Likes

Synchro Shift: Shimano say that it is programmed in the display, not in the derailleurs. Since there is no display for road (and you can't use the XTR display for it), you can't make Synchro Shift work with a road system at the moment.

They say that they will test to see whether Synchro Shift is an added value for road use in the near future, but they can't say if or when it will be available.

posted by Mat Brett [1887 posts]
5th June 2014 - 16:53

6 Likes