Author Topic: di2 rear mech and removing wheel  (Read 512 times)

di2 rear mech and removing wheel
« on: September 07, 2019, 11:42:44 pm »
Hi,

The info I've got with my new bike equipped with an Ultegra Di2 R8050 rear mech states 'be sure to move the lever switch to the OFF position before removing the rear wheel'

The unhelpful picture on the Shimano instruction document also states *Depending on the model, the shape and the lever position may differ.

I can't see anything that looks like a lever/switch on this mech with an On/Off position - have I just got some generic Di2 rear mech instruction that's misleading me?


Re: di2 rear mech and removing wheel
« Reply #1 on: September 07, 2019, 11:59:57 pm »
It's probably referring to the clutch disable lever, which the R8050 doesn't have.

(On mechs that do, it's a conspicuous bit of light grey plastic near the upper jockey wheel)

FifeingEejit

  • Not Small just Far Away at the back
Re: di2 rear mech and removing wheel
« Reply #2 on: September 08, 2019, 12:45:24 am »
It's probably referring to the clutch disable lever, which the R8050 doesn't have.

(On mechs that do, it's a conspicuous bit of light grey plastic near the upper jockey wheel)

It probably is, but only found on the RX?
https://www.bikeradar.com/reviews/components/groupsets/derailleurs/derailleurs-rear/road-bike-derailleur-rear/shimano-ultegra-rx-di2-rear-derailleur-review/

quixoticgeek

  • Mostly Harmless
Re: di2 rear mech and removing wheel
« Reply #3 on: September 08, 2019, 10:15:51 am »

It probably is, but only found on the RX?
https://www.bikeradar.com/reviews/components/groupsets/derailleurs/derailleurs-rear/road-bike-derailleur-rear/shimano-ultegra-rx-di2-rear-derailleur-review/

Found on the RX units of the GRX groupsets, as well as the MTB groupsets.

Grey lever near the upper wheel.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: di2 rear mech and removing wheel
« Reply #4 on: September 08, 2019, 05:07:00 pm »
Thanks all, even with my poor eyesight I can spot the lever in the pics of the RX di2 rear derailleur so I'm happy that I don't have it on mine.

I'm hoping that as long as I shift to the smallest sprocket on the the cassette as usual before I remove the wheel it will be no different from a non di2 bike.

FifeingEejit

  • Not Small just Far Away at the back
Re: di2 rear mech and removing wheel
« Reply #5 on: September 08, 2019, 09:14:00 pm »
Thanks all, even with my poor eyesight I can spot the lever in the pics of the RX di2 rear derailleur so I'm happy that I don't have it on mine.

I'm hoping that as long as I shift to the smallest sprocket on the the cassette as usual before I remove the wheel it will be no different from a non di2 bike.

Just remember that the di2 will prevent the small-small combination.

Re: di2 rear mech and removing wheel
« Reply #6 on: September 08, 2019, 09:25:37 pm »
Thanks all, even with my poor eyesight I can spot the lever in the pics of the RX di2 rear derailleur so I'm happy that I don't have it on mine.

I'm hoping that as long as I shift to the smallest sprocket on the the cassette as usual before I remove the wheel it will be no different from a non di2 bike.

Just remember that the di2 will prevent the small-small combination.

Depends on the mode it’s in IIRC (it also prevent big-big usually, but you need that to check chain length). But in normal shift patterns, yes.
We are making a New World (Paul Nash, 1918)

Re: di2 rear mech and removing wheel
« Reply #7 on: September 08, 2019, 10:46:44 pm »
I've been out on it today and as has been said it doesn't allow small/small but does allow big/big.

It's a compact chainset 50/34, with 11-34 cassette. I've another non di2 bike with a compact chainset and it's a pain to have to change up/down on the cassette in reaction to a change up front. Got to say the synchro modes do an impressive job though of making this a non issue.

I've heard it said that the buttons can be tricky to use in winter gloves, I'm wondering whether I can program the di2 so one or both LHS buttons increase the gear and one or both RHS decrease the gear - like a flappy paddle gearbox (might end up getting 2 shifts up or down for the price of one though if I can't deactivate one on each side?

Will have a look at the app to see what I can do unless anyone can save my time by telling me it can't be done or is not advisable for whatever reason.


quixoticgeek

  • Mostly Harmless
Re: di2 rear mech and removing wheel
« Reply #8 on: September 08, 2019, 10:53:47 pm »
I've been out on it today and as has been said it doesn't allow small/small but does allow big/big.

It's a compact chainset 50/34, with 11-34 cassette. I've another non di2 bike with a compact chainset and it's a pain to have to change up/down on the cassette in reaction to a change up front. Got to say the synchro modes do an impressive job though of making this a non issue.

Syncro shift is just brilliant, I'm so pleased I have it on my bike. Coupled with the shifters on the aerobars, it's fantastic. The best upgrade I've done. And can confirm it does do big/big.

Quote
I've heard it said that the buttons can be tricky to use in winter gloves, I'm wondering whether I can program the di2 so one or both LHS buttons increase the gear and one or both RHS decrease the gear - like a flappy paddle gearbox (might end up getting 2 shifts up or down for the price of one though if I can't deactivate one on each side?

Will have a look at the app to see what I can do unless anyone can save my time by telling me it can't be done or is not advisable for whatever reason.

You can remap every button, so should be do able. Just make sure you check you've got it right. Don't accidentally map all 4 buttons to cassette shift up. DAMHIKT...

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

FifeingEejit

  • Not Small just Far Away at the back
Re: di2 rear mech and removing wheel
« Reply #9 on: September 08, 2019, 10:58:34 pm »
I've got the the hood top buttons set up to shift the rear mech (Left bigger cog, Right smaller cog); this is in part to help with my tendency to need to make a gear adjustment when drinking, eating or taking a photo.

I never got the hang of synchro but then I never persevered with it, the problem being I tend not to back off as much as I would for a rear shift as a front and not being too sure when it's going to shift the front...

Re: di2 rear mech and removing wheel
« Reply #10 on: September 08, 2019, 11:03:06 pm »
Unless they've changed it since I last looked, the biggest problem is you can only completely remap the function of the buttons 100% of the time, so you can't just have flappy paddles in synchro mode and normal F/R shifting in manual mode. I've never had a problem with the buttons with gloves though.

(Also, if you've never connected the app before and it offers to do a firmware update, there's a non-zero chance it'll fail and brick your bike, so don't let it go ahead if you have an important ride tomorrow...)

Quote
I never got the hang of synchro but then I never persevered with it, the problem being I tend not to back off as much as I would for a rear shift as a front and not being too sure when it's going to shift the front...

If you have the SC-MT800 Junction A, it'll do a double beep on the shift before the double shift. The standard road Junction A doesn't seem to have a beeper.

quixoticgeek

  • Mostly Harmless
Re: di2 rear mech and removing wheel
« Reply #11 on: September 08, 2019, 11:10:24 pm »

Quote
I never got the hang of synchro but then I never persevered with it, the problem being I tend not to back off as much as I would for a rear shift as a front and not being too sure when it's going to shift the front...

If you have the SC-MT800 Junction A, it'll do a double beep on the shift before the double shift. The standard road Junction A doesn't seem to have a beeper.

Ooh, how do you turn that on? Mine doesn't do that.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: di2 rear mech and removing wheel
« Reply #12 on: September 08, 2019, 11:15:04 pm »
There are beep settings somewhere in the e-tube app. It'll also do a single beep when you run out of gears.

FifeingEejit

  • Not Small just Far Away at the back
Re: di2 rear mech and removing wheel
« Reply #13 on: September 08, 2019, 11:31:50 pm »
If you have the SC-MT800 Junction A, it'll do a double beep on the shift before the double shift. The standard road Junction A doesn't seem to have a beeper.

Aye, oddly enough I have a road junction A; there usually is a noise AFTER the double shift, it emanates from me.