Thanks to all the contributors in the Plasma 3 TT/ Premium thread, i was able to accomplish this rather quixotic/Cap’n Ahab like objective. Special thanks to fellow forumites tetonrider, Jaymz, Tri-frank, and BergHügi for their time and knowledge on this matter. Things are still not totally finished as i’m waiting for my Nokon brake housings to come in, but here’s an early write up of the whole thing.
I’m not so inclined when it comes to electrical work, so this mean that soldering and wire splicing were out, and i relied on parts readily available.
Frame set up:
-Scott Plasma 3 TT with PRO Missile Evo handlebar and stem
Di2 set up:
-Controlling Junction box: EW-67
-Shifters: R671 shifters on the extensions (i forwent the bull horn shifters)
-Battery: external; long external mount
-Other junction boxes: 3x JC-41
-Wires needed. Wires to rear JC-41: 1000 mm to the battery, 550 mm to the RD, 300 mm to the FD, 300 mm to the EW-67. Wires to the middle JC-41: two coming from the EW-67 and one 1000 mm connecting the middle to the front JC-41. Wires to the front JC-41: the aforementioned 1000 mm to the middle junction and wires from the R671 shifters.
Pictures:
Before installation of the wires
Rear and middle JC-41. The rear JC-41 is in the background, right under the FD. The middle JC-41 is in the foreground and has three connections.
The battery mount. Scott engineers botched this one, and the bosses on the seat tube could accommodate either a battery or a water bottle, but not both, thus requiring some jerry-rigging.
You learn from others. A fellow forumite set up his bike in a similar fashion, with the controlling junction box placed on the top of the BB. This is temporary as additional adjustments may be needed, so it’s tied down with electric tape.
The stem. The stem on the Plasma 3 was specially made to “accommodate” the controlling junction box of a Di-2 7970. Even then, it required the filing down of quite a bit of the box to fit inside the stem. The JC-41 fits nicely in the space. Also, note the brake housing inside (for rear brake). There will also be a short, tightly bend housing for the front, which required the drilling of the stem so that the front brake housing will reach the cable stop of a Tri-Rig Omega.
Front JC-41 and the rear brake housing (in the background) about to be stuffed inside the stem. Space is tight, but it’ll fit.
Actually had the wires from the shifters be arranged at the rear of the JC-41 and wire from the BB area at the front as this apparently saved some space.
For a temporary, proof of concept thing, i routed the wire from the LHS shifter through the extension, risers, and basebar into the stem. No exposed wires here.
Here’s everything stuck inside the stem. You can catch a glimpse of a wire and the JC-41.
Downside is that the length of the wires are too damned long, and i’ll probably have to wrap these around the extensions when everything is finally set up.
Current set up. For ease of adjustment, the wires are not routed through the extension and risers. The PRO Missile Evo allows two sets of width, and the wires are going into the bar where the wider risers would have been.
A shot of the front end.
Things remain to be done: finish drilling the hole in the stem and wire up the brake housing; determine if i need taller risers; and glue on magnets for my eSs aRe aM.
Photo from preliminary fitting session (after cutting seatpost to size)
If i could be of any help re: set up of Di-2 parts in general or with the Plasma in particular, i’d be more than willing to contribute. Thanks for reading.
