Di2 wire needed
 

Hi,

I wired a 7970 Di2 internally, bringing all the wires to the junction box under the BB. Works great but this winter I want to improve it to something more stealthy and secure, with the battery in the seat post and replacing the junction box with hardwired connections in the seat tube.

I was hoping to find the proper connectors to the RD, FD and control box with long enough cables (5 feet) for my needs (I need to bring everything up the seat tube, make all the connections and push everything down) but they don't exist. I was hoping not to have the heat shrink covering the union from the connector to my custom cable running inside the tubing visible from the outside, but it looks like it'll have to be that way.

So, I've been looking for proper wire. I need a 5-conductor wire, black insulation, outside diameter same size as Shimano's, preferably single strand but will use Shimano-style multiple strands if it's all I can find. I never thought this would be so hard to find.

Any suggestions as to where I can find this in Canada or the US?

For a proprietary part, have you tried a bike shop with a Shimano account? Any LBS in the world who has an account with their local Shimano importer should be able to get the required part.

Find the required cable from the EW series of parts and order it. http://techdocs.shimano.com/techdocs...&bmUID=j.dFmXU

Shimano doesn't sell the wire.

If by "single strand" you mean solid wire I would recommend against it as it is less flexible and more susceptible to breaking than stranded wire.

I do not know if the wire will be long enough but computer mice generally have a 5- or 6-conductor very flexible stranded wire that might be repurposed for your project.

The Poster seems in over their head with the project, from the question asked.

take it to a Pro Bike shop.

not to you, you have to go back up the supply chain from Retailer to Distributor ,
and they buy from the Shimano importer to North America.

that's how The Bike-Business model works..

Thanks for the info. The gears don't seem to know this however, as they are currently working fine and I'm confident they will continue to do so when the new configuration is implemented.

Unless causality principles have recently undergone major changes, understanding the model (which I do) or using the distribution channel from a different entry point will not change the fact that Shimano just doesn't sell the wire separately (dixit the Shimano reps here in Canada). All Shimano will sell are the various pre-cut lengths with connectors, which are too short for my project.

Good idea. Might work. I'll see what I can find. Thanks.

Yes, I did mean solid by "single strand". You're right, it is less flexible, but I've used some in my current setup (Northern Telecom phone wire) as well as multiple strand household phone wiring and it's the latter that actually broke after a few months. It was cheaper quality though, than the Shimano wire, with less strands per conductor and a real pita to skin without breaking strands.

For single copper strand: Ethernet cat5 cable.
How many amps do you run trough the cable? (if we can talk about that, then don't use ethernet cable!)

About single strand vs multistrand.. single strand is better when there is no relative movement whatsoever like the electrical wiring in a house. I've seen an art form of electrical wiring on a farm tractor with bare copper single strand wires (very thick gage) bent to shape standing mid-air to prevent shorts - it's not about moving parts, but the relative movement of the cable.

I'd thought of Cat 5 too, but its outside diameter is too big.

I guess I should use multiple strand conductors then. But I need to find some that are as good as the one in the Shimano wire.

I didn't expected this sort of wire to be so hard to find. Digikey has thousands of wires but I couldn't find any that would work for me. I tried electrical supply stores, electronic supply stores, process control system builders, etc.

How much current do the derailleur motors draw from the battery?

Sounds like you have all the answers then . . . except how to buy some wire. Good luck and best wishes.

are you going to use the e tube battery? the gen1 dura ace di2(7970) does not mix with the e tube(ultegra or 9070 11sp dura ace style wiring)

you know.. electrical wire can be harvested out of the ethernet cable without the shielding, and get a shrinktube to make a new insulation for added protection. About signal loss - no worry, it's not that kind of signal disrupted by magnetic waves, and you can keep the twisted pairs of wires for + and - and that acts as a shield against interferences as well.

As for multistrand wires, you can get any usb cable to harvest the wires from it (or mouse cable as said before)

A good electronics store (with solder, IC's, transistors, capacitors, etc) will have a nice collection of multiple gage wires as is (not a cable, just the wire with insulation on it, or just lacquered for making transformer coils and such) some of them being very thin gage. - not too expensive at all but you'd have to buy a roll of 100m or so - still only a few $. If you go this route, you have shrink tubes by the meter for pocket change in such stores.

I'd suggest wire for breadboard prototyping - found in any decent electronics store (that have breadboards and electronics components)

I have no idea, but given the size of the Shimano wires, I suppose it's minimal.

I'll be using this battery.
Yes. Too bad the new generation wiring is incompatible because if I remember correctly this type does come in 1400 mm lengths with a connector, which would've worked for my project and eliminated the visible heat shrink before the wires enter the frame.

Waow. Great idea Asi. Thank you.
Tried a short prototype and your suggestion works great. Don't think I'll keep looking very long for something ready-made now.

+1 mouse or keyboard cable.

IIRC you might find five or more conductors in one with an old PS/2 connector... otherwise many USB cables will have a shield you could probably use as ground.

Or you might find a FireWire (IEEE1394) cable thin enough, they have seven conductors I think.