If you are running a Di2 battery mounted to your saddle rails or seat post what wiring kit/pieces are you using to run the wiring?
Cheers
If you are running a Di2 battery mounted to your saddle rails or seat post what wiring kit/pieces are you using to run the wiring?
Cheers
shimano actually makes a special harness for such configurations. the normal internal harness is part # SM-EW-7975. the one you want (it’s a little tougher to find) is EW-7975-A-2. i believe the wires to the battery is ~100cm long. it’s confusing because it’s called the “short battery mount” version – and that’s true. the actual MOUNT for the battery is short, but the wire is longer.
alternately, you could just cut and splice the battery wire from an existing setup. it’s really easy.
Just to clarify, the EW-7975-A2 harness is intended for internal routing.
Just to clarify, the EW-7975-A2 harness is intended for internal routing.
that is correct.
Thank you for the reply. That is what Shimano told me, but my impression from the pro team mechanics is you can’t take the seat post out. The HTC mech told me to get the 7975A1 wiring get and purchase a separate rear derailleur cable to go from the wiring kit junction to the short battery?
Thank you for the reply. That is what Shimano told me, but my impression from the pro team mechanics is you can’t take the seat post out. The HTC mech told me to get the 7975A1 wiring get and purchase a separate rear derailleur cable to go from the wiring kit junction to the short battery?
which HTC mechanic?
the wires inside the RD lead are different from those inside the battery lead.
if you have some slack, you can remove your seatpost with the long lead. switching posts would be tough.
Tried to send you this via PM, but I cannot send right now.
As for what you need, I’m not going to question what the team mechanic said, but I’ll give you my guidance based on installing Di2 in numerous bikes, externally and internally, and recently cutting and splicing wires on an install.
EW-7975 is the standard internal wire kit. (There are some variations, but they are all EW-7975’s.)
The standard wire kit has a battery lead that is 400mm, or roughly 16 inches. The reason that that is the standard is because it is plenty when running the lead from the bottom bracket area to a battery mounted using the bottle cage bolts.
What you want to do is to run the battery at the top of the seat post. My saddle height is 750mm from the center of the bottom bracket. In your setup, the battery sits below the saddle, and the wire junction is above the bottom bracket, so the distance is probably less than or equal to your saddle height.
Why does this matter? Well, EW-7975-A-2 has a battery lead that is 1,000mm, or 25 inches. In my case, I would have an extra 250mm = 10" of wire. I could raise the post up and down and take it out of the frame.
However, the “problem” is that the junction is down near the bottom bracket. That’s where the wire plugs in. You can remove the post, but it will still be attached. Without access to the bottom bracket, you won’t be able to easily unplug that wire. Do you want to? The other wrinkle is that in order to weather seal it, you need to use heat shrink, and if you want to disconnect the wire you’ll have to cut the heat shrink and re-wrap it.
If you anticipate needing to remove the post completely and disconnect the wire, the only solution is to have a wire whose connector rests at or just above the top of your seat tube. What Hermann suggests (buying a spare RD wire then using it as an insert) just won’t work without modification as I see it. You see, the wires in an RD wire are different than the battery wire. The RD wire has 2 wires for power and 2 wires for derailleur signals. The Battery wire has 4 wires – basically a double set of power wires. Further, the RD wire has an RD connector at one end, which cannot plug into a battery even if you wanted to.
At a minimum, you’d have to cut the connectors and splice wires…but the thing is the shimano connectors are impossible to find.
What I would suggest if you really NEED to pull the seat post often AND disconnect the wires is to buy the EW-7975-A-2 kit (you can buy any kit…but that would make it easier). Then, you need to cut the wires at the middle and solder a male connector on one end and a female on the other. Ideally, these are weather sealed. The soldering is simple, but it’s really the only way.
The other thing is the 7975 (regular) kit includes a metal mount designed to bolt onto the bottle cage bolts. The A-2 kit includes a short metal mount. I’m not sure if you need that (how are you attaching this to the saddle?), but the battery lead is hardwired to that thing. If you are using another battery holder, then you’re going to have to cut that cable ad splice.
I hope this helps. I sent you my phone # in an earlier PM so you can feel free to call me if you wish to discuss this live. I can also help you with the parts and wiring, too.
Good luck!
If you are running a Di2 battery mounted to your saddle rails or seat post what wiring kit/pieces are you using to run the wiring?
Cheers
This is how the teams run their DA TT bikes and how our F2x cyclo-cross bike comes equipped. Pulling the plug can be tricky but both bikes have an access hole under the BB shell so you can pop it open and get to the junction B and unplug the battery.
I use EW7975A with the short battery mount with M4 rivnuts in the seatpost itself. You can also set up the battery using rear relfector brackets.
Good Luck
My 2012 Felt DA frame came with a second Felt seatpost with the cutout for the Shimano battery. My builder left extra cable at the junction box under the BB that would run up the seattube, through the seatpost and out the top to the battery mount.
Waupaca11 may I ask which DA you got? I just picked up my DA2 and only have one seat post so thinking you got the 1. I’m already thinking of putting the battery in the seat post, have you had good results? Thx!
My Di2 battery mount is actually inside my seat tube. Love it but can’t take credit for the design and/or how it would be installed.
I got the DA1. I’ll be selling the post with the battery instal as I don’t need it
I sell a battery for inside the seat post on eBay
http://www.ebay.com/itm/300690872368?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649#ht_1666wt_1140
http://www.ebay.com/itm/290700600796?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649#ht_1649wt_1140
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updated links, also di2diy@gmail.com
http://www.ebay.com/itm/291271828873?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
http://www.ebay.com/itm/300924464023?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
http://www.ebay.com/itm/291538355233?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
http://www.ebay.com/itm/301749185401?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
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