This failed as I had not realised that I needed a Shimano SM-EWW01 device rather than either a EX-WU101 or EX-WU111. The SM-EWW01 is is obsolete so the only routes forward were a new battery that supported the newer WU series devices or I needed to get a second hand SM-EWW01 from (for example) EBay
I spent the past 9 months or so looking on EBay and bidding on the few units that came up for sale, I was unsuccessful on 2-3 occasions missing the winning bid by a few £. Amazingly in early September another unit came up and I bid again (not holding much hope of winning) and I ended up the winning bidder for less than my maximum bid. This particular item came without the O-Ring strap, spare rubber grommet/seat nor a cable. I ordered the shortest cable you can get (150mm):
Coming in at ~£18 one can only guess at the profit margin.
When the cable I arrived I fitted the device - it took about 5 minutes all in and most of that was fiddling with the visual appearance rather than anything difficult.
Without the O-Ring (official part at ~£8) I fitted it in position with Electrical tape:
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| Here's a direct side on view |
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| Here's a slightly oblique view |
I was able to push the original rear derailleur cable back into the frame to lose some of the excess length. With it fitted in this location it's not that bad a sight. I taped the excess length to the seat stay as well to avoid it getting caught and pulled off
Clearly with the newer unit (the EW-WU11) it is smaller and able to be hidden in the frame - if I could use one of these I would have fitted it in the seat tube below the battery, so this unit is less visually satisfying.
Turning the unit on (by initiating a gear shift) my Garmin found the unit and I was able to set up a screen on it:
There are other screen elements available
A week or so later I was looking through my "cycling odds and sods" drawer and found a suitable O-Ring, which is now fitted instead of the electrical tape (rubbish phone photos):
I have however left the electrical tape to hold the cables to the seat stay. A bit of belt and braces perhaps if the O-Ring fails.
A couple of rides in and it's not transformed my riding. I need to edit one of my standard screens to add the rear gear number and this is what will be a big change and will stop me keep looking down at the rear cassette. However now that the dirtier autumn and winter rides are here its less likely I'll be riding my Giant which is after all my "best" bike and the one I try to keep clean and dry. What will be useful is being able to read the battery level as a percentage rather than the standard process of pressing and holding a lever and reading the LED flash code from the junction box
At the moment the Di2 data from the Garmin remains locked in the .fit file, and Strava does nothing with it. I have found a .fit file SDK which will allow me to get the data out. At this time the plan is to write a small standalone utility just for the Di2 data and then incorporate that into my Strava Data Analysis tool (Here).
The first aim would be to plot the gear number vs. time or distance and also calculate and display a statistical analysis of the time in each of the gear. Now (it's September 2019) that the evenings are drawing in this is more likely to happen than in the summer
It is important to note the newer models (EX-WU111) supports Bluetooth as well and allows the owner to programme the Di2 System using an App as well as the original method of connecting via the special USB adaptor and using the Shimano E-Tube software. I am more than happy to use E-Tube as I am much more of a laptop person than an App person:
