DI2 junction box

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DCnoJ
Posts: 104
Joined: Wed Mar 23, 2011 6:50 am

by DCnoJ

mr4fox wrote:I currently have mine mounted under the water bottle cage on the seat post. i have connected the right shifter to the left shifter. then a single long cable running form the left shifter to the junction B (4 way connector) in the BB. from there one wire goes out to the 3port junction box under the bottle cage. From there another cable goes to the front derailleur. There is a bit of cable slack that has to dealt with but no drilling of carbon is needed...and honestly, i never see any of it when i look at my bike plus i can still access while I'm riding if necessary. But its not perfectly neat and i know that bugs people.

Other options I've seen are the BLK-Tek bars http://www.blktec-cycles.com/collection ... roducts/r5
or the Syncros aero road bars that come on the 2016 Scott foil...
http://www.syncros.com/syncros/global/e ... r-Stem-420


a friend of mine has Enve SES Areo road bars and PRO Tharsis stem. looks pretty cool. He daringly drilled a hole in the back part of the clamped section of the cars so the cables ran from inside the bars directly into the Tharsis stem. so the only. pretty neat set up...I'm too chicken to drill a hole in the bars until an engineer tells me it should be safe.

Dont know why more bars and stems aren't made to hide the junction box. it seems a pretty popular topic.
I didn't know that you could connect the two shifters together. That would help me since I can't fit more than one wire through my headtube entry point.

by Weenie


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mr4fox
Posts: 276
Joined: Sat May 15, 2010 2:01 pm

by mr4fox

connecting the one shifter to the other works fine. Internally routed bars can pose a challenge as the holes for the cables are not really meant to accommodate a brake cable and the heads of 2 di2 cables... i had to slightly file one of the holes on my aeronova bars to get the second cable head through but it worked in the end.

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eliflap-scalpel
Posts: 870
Joined: Sun May 25, 2008 10:12 pm
Location: italy
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by eliflap-scalpel

use sugru to attach the junction box
http://eliflap.it/

Dagger9903
Posts: 52
Joined: Mon May 21, 2012 7:40 pm

by Dagger9903

Just curious, does anyone have the dimensions of the junction box for di2? Contemplating a Madone 9 EPS build but want to put the Interface in the dedicated Junction Box location. Looks like the EPS V3 interface is 23.1x22.5x47.6.

Thanks!

glepore
Posts: 1408
Joined: Thu Mar 28, 2013 4:42 pm
Location: Virginia USA

by glepore

44mm x 16mmx22. Just measured a 3 port on my desk.
Cysco Ti custom Campy SR mechanical (6.9);Berk custom (5.6); Serotta Ottrott(6.8) ; Anvil Custom steel Etap;1996 Colnago Technos Record

11.4
Posts: 1095
Joined: Tue May 23, 2006 4:33 am

by 11.4

I was experimenting today with layouts since the bike was apart anyway. I've already been able to use the Junction A box without a Junction B at all. As described above, one cable from lever to lever. Then one cable from lever into the frame and down the down tube (I was setting this up on a CAAD10 with the very nice mated port on the side of the head tube for both brake housing and Di2 wire). Those two are packaged in a piece of heat-shrink tubing which, when shrunk, looks very neat and professional.

At that point, there are no junction boxes external on the frame. The Junction A goes at the bottom of the seat tube and is used just like a Junction B is, except the A box has the internal intelligence while the B box is simply a four-way connector. The drawback to this approach is that there's no charging port accessible, but I've found the battery lasts close to a year between charges and I'm charging well before it's needed. So I just do it when I'm opening the frame up anyway. I did make the long run from a lever through the frame to the A box just long enough so the A junction is actually mounted right on the bottom of the seat post battery and the junction box and battery both are accessed when the seat post is pulled. It makes it quite easy.

I have an S&S coupled ti frame that is also set up for internal Di2, and I use the A box as a disconnector at the down-tube S&S coupler. Since I have to break the wire anyway with a junction box, I use one box for two purposes instead of installing a superfluous B box.

glepore
Posts: 1408
Joined: Thu Mar 28, 2013 4:42 pm
Location: Virginia USA

by glepore

I couldn't live with the A junction internal, I go about 3 months between charges, so it's attached (using the stock mount with a hole drilled between the tabs) on a boss set up for an external battery on the downtube. This is on a Willier Cento 1 Air. Wires shifter to shifter, one to a B in the downtube. The other B's are front and rd, with the battery going to the A outside (only because I had a short cable where that worked but the B in the downtube was too far. This is di2 bike number 3 and this is my favorite layout by far, the front end looks very clean.
Cysco Ti custom Campy SR mechanical (6.9);Berk custom (5.6); Serotta Ottrott(6.8) ; Anvil Custom steel Etap;1996 Colnago Technos Record

superdx
Posts: 524
Joined: Sun Jun 29, 2014 1:27 pm

by superdx

Man I must be the only one that likes the look of the junction box under the stem!

DartanianX
Posts: 616
Joined: Sun Nov 13, 2011 6:00 am

by DartanianX

Drilling a hole between the tabs is the easiest way to do it.

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DartanianX
Posts: 616
Joined: Sun Nov 13, 2011 6:00 am

by DartanianX

Hydro shifters with only one port make things a bit harder.

Some cutting and splicing was needed.

Still the cleanest I've seen. I'll need to take some proper photos for you all.

Image

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bonedpwinkle
Posts: 61
Joined: Thu Mar 20, 2008 8:39 pm

by bonedpwinkle

Does anyone know if it would be possible to utilize an additional A junction box for charging purposes only? For instance, have the system's A junction internal, but simply attach a separate A junction with the charger attached, and plug it into the rear derailleur port to charge the battery?

11.4
Posts: 1095
Joined: Tue May 23, 2006 4:33 am

by 11.4

bonedpwinkle wrote:Does anyone know if it would be possible to utilize an additional A junction box for charging purposes only? For instance, have the system's A junction internal, but simply attach a separate A junction with the charger attached, and plug it into the rear derailleur port to charge the battery?


I'm playing with this at present so I can hide the stem junction box completely inside the frame. When I set it up first, it didn't work. Disconnected stuff and reduced it to one A box and did a firmware update, and it worked fine. Trying to do a firmware update on two A boxes only upgrades one so I had to update one, then remove it and replace it with the other, then keep both updated identically. I'm not sure if this is a long-term solution, but at the moment it seems to be working for me.

Timmy269
Posts: 243
Joined: Tue Nov 25, 2014 2:34 pm

by Timmy269

Nejmann wrote:Another option, is the s-works stem, with the built in mount? So you loose the rubberband?

Do you have a link for that stem, I can't find it.

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53x12
Posts: 3708
Joined: Fri Sep 15, 2006 6:02 am
Location: On the bike

by 53x12

Timmy269 wrote:
Nejmann wrote:Another option, is the s-works stem, with the built in mount? So you loose the rubberband?

Do you have a link for that stem, I can't find it.


You could also consider the 3T Integra Team stem.

Image
"Marginal gains are the only gains when all that's left to gain is in the margins."

DartanianX
Posts: 616
Joined: Sun Nov 13, 2011 6:00 am

by DartanianX

S-Works SL Stem with Di2 clip.

Image

Image

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by Weenie


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