Shimano XT Di2: eight questions about the new electronic mountain bike gear shifter
With the Shimano XT Di2 the XT Group now is also electronic, too. Shifting is faster, easier and more effective thanks to automatic shifting. Reason enough to speak with Michael Wild, PR Marketing Manager at Shimano about some fundamental aspects of the development, function and handling of the electronic mountain bike gear shifter.
What changes had to be made to adapt the electronic shifter from racing bikes to the requirements of mountain bikes?
Naturally our know-how and many years of experience in the racing bike area influenced us in the development of the mountain bike Di2 Groups. However it involved a complete redevelopment and a lot more than merely taking racing bike components, altering the design and adapting them to mountain bike conditions. On the one hand the components, in particular the front and the rear dérailleurs, had to be made more robust for the mountain bike sector than delicate racing bike components. On the other hand the components must be able to handle quite different gear ratios and gear ranges. And on the software side we also have the synchro shift function which enables two and three tier systems to be operated with just one shifter which is completely new territory in the mountain bike sector.
How do you guarantee that the shifter will still work reliably in very muddy conditions?
One central element of this of course is that all electronic components must be extremely well protected against moisture. Where the actual tolerance for mud etc. is concerned there is fundamentally no difference to the mechanical components which have also been reliably doing their job for decades under muddy conditions. On the contrary: thanks to very powerful electronic actuators the front and rear dérailleurs do not require increased operating force in extremely muddy conditions and this reduces the load on the system. The fact that SHIMANO's electronic Di2 components can also function perfectly in slush, mud, snow, ice and rain shows that the Di2 parts from racing bikes will be one hundred per cent reliable for many years, from winter to winter performing at the highest level. It goes without saying that the mountain bike components will not be inferior to these.
How long does the battery last?
Battery duration always depends on many different factors, including shifting frequency and/or shifting characteristics and above all temperature. Under normal conditions one charge is sufficient for 500 to 1500 kilometres of unlimited riding pleasure.
Are there different options for mounting the battery for the gears on the bike?
There are two basic battery types: one is block-shaped and is externally mounted and the other is a slim cylinder which is normally mounted internally. The former is mounted on the frame in a special mount and is removed from this for charging. The internal battery can generally be mounted anywhere inside the bike as it is directly connected to the system using an e-tube cable. SHIMANO's accessories brand PRO for example offers various seat posts with an integrated mount for the internal battery. With a corresponding stem fixed in place without a headset clamp the battery can alternately be integrated into the steerer tube so that a dropper seat post can be used, for example. Provided bike manufacturers allow for corresponding mounting options it is basically possible to mount the battery anywhere you like. There is also a special case for the internal battery which houses the battery and can be affixed to the frame using the bottle holder boreholes.
Is it easy to swap out the battery or remove it for charging?
The external battery is very simple to remove for charging. The internal battery remains in the bike and is charged using a separate charger connector on the upper connector unit, the display. Depending on the temperature both types of battery charge in around two hours.
Can I ride without the additional display if I connect to the gearing system via Bluetooth using a compatible bike computer?
The display is significantly more than just an information display. It serves as the upper connector unit which connects the cockpit elements (shift left, shift right, display) to the other components (battery, front and rear dérailleurs). Also situated on the display are the charger connector and the shifter which switches between synchro shift modes 1 and 2 or manual mode.
Are there any bike computers or eMTB displays which are compatible with the Di2 system?
We do not have any information regarding this. Computer manufacturers are welcome to develop devices which can read and display information sent from the wireless unit of the Di2 system by ANT+. The Di2 system merely sends information via ANT+. How this is handled is a matter for third party manufacturers.
Can I "upgrade" existing XT equipment by buying the electronic components?
Yes this is not a problem.
The electronic Shimano XT Di2 gear system is built into to ROTWILD cross country models R.C+ HT EVO, R.C+ FS EVO and R.C1 FS EVO and in the all mountain bikes R.X+ FS EVO, R.X1 FS EVO and R.X2 FS EVO.
More information about the functionality of the gear system can be found in this article on enduro-mtb.com.