Di2 TT build, small parts not to forget

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Tinea Pedis
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by Tinea Pedis

My first Di2 build - and a TT bike (Argon18 E-118) at that. Having to assemble the build myself, keen to avoid getting to the day of putting it together and forgetting something basic.

Will be 6870 e-tube. Have junction box, but unsure of:

- wiring kit needed (SM-EW79A-E ?)

- battery kit

- bar end shifters (I recall 6770 shifters can be upgraded to 11sp?)


Feel like a dinosaur doing this. Cables so much more simple :doh:

goodboyr
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by goodboyr

There are some good resources to help you plan. You use E tube wiring to connect up all your devices. All e tube wires are the same, you just choose the length you need. The component you've quoted is for the older system. Newer E tube systems use EW90 Junction connection at the front. See attached as a good start:

http://si.shimano.com/php/download.php?file=pdf/dm/DM-DA0001-04-ENG.pdf

by Weenie


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Pokerface07
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by Pokerface07

Assuming this is 11-speed?

6870 Front Mech
6870 Rear Mech
R671 TT shifters
ST-6871 Brake Levers/Shifters (optional)
Junction A (which you have). You need a 3-port one if you're not using the brake lever shifters. You need a 5-port one if using both the brake levels and the extension shifters.

SM-JC41 Junction B (little small 4-port that goes at BB)


Cables:
1 x 1000mm from junction A to Junction B (at BB usually)
1 x 650mm junction B to rear mech
1 x 400mm junction B to front mech
1 x 600mm junction B to internal battery (or external, depending on your choice)


Will also need a battery. Seat-tube one is SMBTR2 Di2 E-tube Battery. External one needs a frame mount.


That's all the bits you should need, plus usual stuff life brake cables, etc.
Twitter: @FormerTTchamp https://twitter.com/FormerTTchamp

hornedfrog
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by hornedfrog

Also, another option instead of the R671 shifters are the SW 9071 shifters. They are a one button design that only controls the rear mech. I prefer the shape of them when compared to the two button design. Never really feel I need to shift the front mech when in the extensions.

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Pokerface07
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by Pokerface07

hornedfrog wrote:Also, another option instead of the R671 shifters are the SW 9071 shifters. They are a one button design that only controls the rear mech. I prefer the shape of them when compared to the two button design. Never really feel I need to shift the front mech when in the extensions.



Only if you have the brake lever shifters of course! My TT bike doesn't have them so I personally need to shifter from the extensions.
Twitter: @FormerTTchamp https://twitter.com/FormerTTchamp

hornedfrog
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by hornedfrog

Thanks, forgot to mention that as the 118s come stock with TRP levers if I remember correctly...


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Tinea Pedis
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by Tinea Pedis

So I picked up a 7970 Di2 TT kit, only previous owner was running an internal battery (parts came out of a BMC TM01).

Having some difficulty working out what battery mount I'll need. Or even internal battery. This is a shot of where the mount is (so assuming it's a short bracket).

Image

dwb
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by dwb

Are you still doing 6870 e-tube? 7970 wires are not compatible with any other DI2...

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Tinea Pedis
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by Tinea Pedis

Aware that they're not compatible.

But, as mentioned, picked up a cheap 7970 Di2 kit so using that instead. I might now have access to a short mount bracket, so will run with that instead of worrying about an internal one.

by Weenie


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