Electronic & Hydraulic Shifting (Di2, Ui2, customisations)

New and exciting bleed problem. It looks like my front brake is leaking from the bleed nipple on the caliper. It's tightened properly but nfc what's going on. Anyone had this?

Shimano?

Might be worth putting a query into the disc brakes thread

Oh yeah, wrong thread. As it stands I bought a better bleed kit and will see if that sorts it

Got a problem with an XT display/junction-A I think.

Bought a new battery a few months ago (see this thread, passim) and if I leave the bike for a week or so, the battery drains to empty.

Connections:

Pave shifter -> Display

Display -> BTC-1 case (inc a "junction-B" style passive 6-port) contains cylindrical battery

Case -> RD-6870

Drain doesn't seem to happen when I unplug the display -> case cable at the display end. Still got the 5-port I had before the display, so I could try leaving that connected for a week, then re-connecting the display for its lovely indication of battery status...

Gah, this worked so well when I left it alone (except when my previous battery died, before I switched from 6-port to display).

6-port? Bin
Display? Bin
5-port Win.

The display has Bluetooth right? I'd put money on it still thinking it has an active connection to the eTube app. Try opening the app, making sure you definitely disconnect the BT connection, then exit app

The 6-port is part of the case, and without it I'd have to route another cable up to the junction.

5-port is essentially a 2-port now because I got it used without enough bungs and the unused connections have corroded.

I've never used BT with it, but the previous owner may have. I'll connect it up to the computer tomorrow and see what settings I can see.

Di2 6870 question: can the shifter ports be used as a junction B box for anything, or just for the sprinter buttons?

Considering hiding a battery in some bars and it would be good if I could
cable it to the shifter then just one cable on from shifter to the junction A under the stem.

2 of them are proper Di2 ports, the third is for buttons only.

Perfect, ta.

Anyone have a spare downtube/ B junction?

My 8050 rear derailleur got very upset during its last ride and wouldn't shift out of 34/28 coming over the top of a hill full gas. Motor started making a grinding noise, like nothing inside was engaging properly. Seems like it's now permanently in crash recovery mode - After resetting at the junction and pressing the shifter it makes the tic-tic-tic noise like it's jammed. Motor/cage remain disconnected and I can move by hand. Everything works with a 6870 derailleur swapped in.

Plugging the charger in to the junction and running e-tube recognises the derailleur.

Any top tips before I find a shop with the proper diagnostics box thing or consider it toasted?

Crash protection is a spring-loaded mechanical breakaway device outside the motor housing. If you look at axle coming out of the motor (towards the cassette), there's a silver cam that should still spin as normal when you shift. If it doesn't, the internal gear train is knackered.

You'll see a spring loaded arm that presses on the cam. That's the crash protection mechanism. If it's engaged with the cam then crash protection is not the problem.

Thanks for sending that over. Seems toasted - Cam not moving or engaged, just the unhappy tic-tic-tic.

Hi, I’ve got my first electronic groupset on the way, just wondered whether any of you find the auto functions (synchro, compensating mode etc) useful or if people tend to try them out for a bit then revert to full manual control. Cheers.

Mine has been in permanent full synchro for as long as I've had it. I've never had any desire to switch it off or override it.

What do you mean by "compensating mode"?

Di2 - I left all mine set to the middle ground. All it does is stop you running Small x smallest two cogs.

Ah gotcha thanks both.
Compensating mode is Sram’s thing where it will shift one or two cogs at the rear when you change the front to give you a natural next gear rather than a big jump. I take some satisfaction when executing a simultaneous shift like that on a mechanical system, silly as it sounds.

I use the semi-syncro (shifting the rear when you do the front) and it's been brilliant. I didn't get on with full synchro at all, tried it once and didn't like it

I use 1 gear compensating on SRAM Force AXS. As you say, on a mechanical system I would almost always shift them together, so that setting makes most sense for how my habit is already trained.

Cool, thanks all. Surprises me all this, I had assumed the automated modes wouldn’t be that useful in practice but I’ll look forward to giving it a go.

The mode where you shift from big ring to little, say at the bottom of a climb, but the rear derailleur shifts to keep you in the same ratio.....I find it super annoying as you have to then shift again on the rear to get the big change in gearing.

I know some people love it but for me it's the opposite of what I want - especially when it can automatically puts you into 36x13..

This guy on FB did a really nice job on hiding all the Di2 cables within the frameset:

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I'm in contact with this guy on-here as he wants to do the same thing with my liquigas supersix