Here’s a video of the Shimano Alfine-11 Di2 system in action on the bench.
This is an internally geared hub so the wheel doesn’t need to be spinning to shift. A little anti-climactic, really, but it does give a good idea how fast this thing shifts. These components are all part of Shimano’s “Comfort” group including the motor, battery, and display connected in a star configuration to a single coupler. The shifter connects to the display.
This all worked perfectly out of the box. When I hooked up the e-tube project software using the charger, each component’s firmware was upgraded. Then I adjusted the configuration to the fastest shift settings and enabled multi-shift. So you don’t necessarily need to use the software but it enables some pretty powerful things, for free, if you have a Windows machine to run it on. If you don’t, any self-respecting bike shop selling Di2 components should be able to program the system for you.
As you can hear, shifting is pretty snappy. Almost as quick as a twist shifter and without any mechanical delays, and much quicker than a trigger shifter. In it’s fastest shift setting, it’s easy to accidentally double-shift as you can see. At the normal, factory-default shift speed double shifts aren’t likely. I have the system programmed to do a triple shift when a button is pressed and held. You can also configure it for a double or turn multi-shifting off. I’ll experiment with this when I get the system installed but I suspect I’ll back off the speed a notch or two to avoid the double shifts.
Though I’d still prefer a twist, or grip, shifter for my trike, the button shifter does a good job. This is hard to tell from the pictures on the internet but there are two buttons—press the big obvious one to shift up and press the little platform around the bug button to shift down. Shimano offers STI shifters for Di2 and I think a trigger shifter as well, but no twist shifter.
The display shows the battery’s state of charge and the current gear selection. The “M” represents manual mode, as opposed to synchronous mode. Without a front derailleur, Synchronous mode makes no sense, so the M is always on. Unfortunately I haven’t found a way turn this useless indicator off. By default the entire display turns off after 300 seconds. This time is configurable through the software.
This is the SM_BTR2 battery and is designed to live inside the seat post of an upright bike. On my recumbent trike I’ll probably mount it inside the front boom. I have no experience of my own yet, but I’ve read reports of battery life anywhere from a couple weeks to an entire season. Assuming reality is somewhere in the middle I think it will be fine.
Charging as well as upgrading firmware and configuring the system is done through a USB port in the display, so the battery never has to be removed. Note that Shimano sells a programming device for about $150 that is separate from the $76 battery charger shown here. Save your money as the charger does everything necessary. As far as I can tell the only thing it doesn’t do is a “system error check”.
All of the Di2 components feel solid and well designed. I’m looking forward to seeing how it works on the road.