Shimano Di2 Synchro Shift - Anyone use?

[saab2000]

I have a GRX groupset on a gravel bike and it functions pretty well. I can't connect to the app unfortunately but that's a long story (see below). I hope to be able to at some point.

Right now it's fully manual and that's OK but the other day on a challenging gravel ride with lots of short, steep, punchy climbs there was a lot of shifting from the big to the small ring and with a 17-tooth difference between them it means at least one and often two shifts on the rear to compensate.

Does anyone ride with the Synchro shift programmed? I guess there are two options, semi-automatic shifting and full automatic (no, not like a car, but I think most here know to what I'm referring) and they sound pretty good.

It sounds like something I might be interested in getting programmed.

For those interested, I can't get the app to connect because I can't do a firmware installation (as I understand it) because I don't own a Microsoft Windows based computer, nor to I have easy access to one at the moment. And I'm not leaving the bike at the LBS for two months because they're backed up. I did the Di2 installation myself last fall and the system bricked itself when I tried to do a firmware update over the app on initial startup. Shimano replaced a bunch of stuff under warranty and the LBS got it running but now it won't connect to the app on my phone. They don't recognize each other. I have a guy who will help out with this but he lives a couple hundred miles away. I digress, but it's a bit of a sore point with me that there's little setup information with a product this expensive. I do all my own work and have for decades and the setup was ridiculous and remains so because it's not accessible via the phone app.

That gripe aside, it works very well. I'm especially pleased with the disc brakes.



Anyway, that's the back story, which isn't really my question. Anyone use the Synchro shifting? Do you like it?

[gone]

I use it on my two Di2 equipped bikes and love it! I use mode 2. I’ve tried full synchro on a number of occasions but am always “surprised” when it shifts. That might be because I’m using it with big cassettes (11x36), it could be that with e.g., an 11x27 it might not be as noticeable/jarring.

At any rate, mode 2 basically does what you’d do anyway when changing between chainrings - shifts the back up/down a couple of cogs.

[Cat3roadracer]

"Technology will save us, if it doesn't kill us first." - TK

[saab2000]

Originally Posted by Cat3roadracer

"Technology will save us, if it doesn't kill us first." - TK

Yeah, I'm uneasy with this piece of tech. But many people love it and the builder (Mike) suggested it so I went ahead. It really does work well now that it's running but I'm not 100% I can see the point because mechanical shifting is so good. That said, the levers are really comfortable.

Anyway, I have it and I'm not getting rid of it anytime soon so I may as well use it to its maximum capacity.

[BRad704]

I've wondered about the full syncho as well. Being new to Di2 this summer, I still have to actively THINK about what each button does before I shift to anything except Rear Derailleur Go Faster.

Can't use it yet becuase I need a newer battery, but I'm synch-urious to see what others here have experienced as well.

[gone]

A few additional comments on full synchro.

As I said before, I'm "surprised" when it shifts but to be more precise, it's when it shifts from the big to small chainring and the ensuing shift of the cassette that I find jarring.

When it shifts from the small to the big ring, it happens so smoothly I find myself looking down to see if it did in fact shift.

If the big to small were that smooth I'd be all over it.

Oh, and for the tin-foil anti technologists out there. I was on a long ride (400K) and the left shifter started failing intermittently then stopped working altogether. I found out later than when I redid the bar tape I'd somehow pulled the lead so that it was loose and was barely making connection.

So no big ring shifts. I'd been grinding into the wind for hours and finally had a tail wind and was stuck on the small ring - crap!

Brainstorm! Switched to full synchro which only uses the right shifter - bingo!

Oh, and it was pissing down rain.

So yeah, you can say the loose connection wouldn't have happened with a mechanical system - ever broken a shifter cable? Ever replaced one at 1:00 AM in pouring rain?

Pushed a button, changed modes, onward.

So it does have its advantages.

Cue the "yeah, but your battery could go dead", "I've heard it just 'locks up'", ..., stories.

I've done a number of long rides with Di2 including LEL (where I had hours and hours of pouring rain) and it's been flawless. Although I did have the capability of recharging the battery while riding (dyno hub), I did LEL on a single charge and still had plenty of life left in the battery after.

And I agree: mechanical shifting is really good, I've got it (Campy, Shimano and SRAM) on other bikes. But: I also have carpal tunnel in both hands and after a few 200+ mile days in a row on crap roads I really have a hard time shifting, especially onto the big ring, and I frequently mis-shift the rear (partially on the cog because I didn't push hard enough). Di2: push a button, perfect shifting every time.

[jb_11]

Originally Posted by saab2000

For those interested, I can't get the app to connect because I can't do a firmware installation (as I understand it) because I don't own a Microsoft Windows based computer, nor to I have easy access to one at the moment. And I'm not leaving the bike at the LBS for two months because they're backed up. I did the Di2 installation myself last fall and the system bricked itself when I tried to do a firmware update over the app on initial startup. Shimano replaced a bunch of stuff under warranty and the LBS got it running but now it won't connect to the app on my phone. They don't recognize each other. I have a guy who will help out with this but he lives a couple hundred miles away. I digress, but it's a bit of a sore point with me that there's little setup information with a product this expensive. I do all my own work and have for decades and the setup was ridiculous and remains so because it's not accessible via the phone app.

Have you tried accessing the auto shift or sychroshift modes by double pressing the button by the Di2 charger/com port? It may already be programmed for you. You might not be able to fine tune it without a PC or working ap, but maybe you can try it out at least.

Each double press will cycle you through three mode settings. I think by default one is normal, two is synchro, and three is full auto (as indicated by the number of light flashes after a double press).

[Bob Ross]

My wife had blip-shifters added to her bike recently, and the shop that installed them also re-programmed her Di2 to do Syncro Shift

...without telling her.

Now that she knows that it's not broken, and also why it's doing what it's doing when it does it ...she still hates it. In short, because it condescends towards the rider: "You don't want to be in that gear combination, let me make a different decision for you."

Eat schidt, Shimano. This is not Ms. Thing's first rodeo, she's been riding long enough that she knows how not to crosschain and when one might want to be crosschained. Doesn't need any help from a computer.

We're disabling Syncro Shift later this week.

[jb_11]

Originally Posted by Bob Ross

My wife had blip-shifters added to her bike recently, and the shop that installed them also re-programmed her Di2 to do Syncro Shift

...without telling her.

Now that she knows that it's not broken, and also why it's doing what it's doing when it does it ...she still hates it. In short, because it condescends towards the rider: "You don't want to be in that gear combination, let me make a different decision for you."

Eat schidt, Shimano. This is not Ms. Thing's first rodeo, she's been riding long enough that she knows how not to crosschain and when one might want to be crosschained. Doesn't need any help from a computer.

We're disabling Syncro Shift later this week.

As I stated above. A double press of the button at the charge/com port cycles you through the different modes. Easy change.

[eddief]

as i thought it would avoid dealing with shifting the rear one or two cogs every time i shifted the chainrings. in the end, it mostly never knew what i really needed it to do. it makes a difference what sort of incline you are heading for and synchro only knows one way. if you are hitting a bump then you might need 1 gear in the back. if you are hitting a wall you might need 2 gears in the back. if you want to stay in the saddle, you want one thing. if you decide to stand on it, you'll want something else.

i turned off synchro and because Di2 shifting both front and rear is lightning quick, now i have taught myself to simply tap the rear shift button most of time at the exact same time i am pressing the front button. you can do them both at the same time and have the control you need for each climbing situation.

[justaute]

Have you tried either Android or ipad (if you have any of these)? I connected and updated firmware using both.

[CTracer]

I use the "semi-synchro" mode on my primary bike and I like it. Now when I ride my other bikes I kind of miss it but have not gotten around to programming them and/or some of my bikes don't have d-fly (I no longer have any non-Di2 bikes - 1st world problems!).

[damocles]

Semi synchro is awesome for me. 95% of the time it does exactly what I would have to do manually. The other 5% I adjust as needed.

[glepore]

+1. I like semi. But you need to adjust your shift to earlier than you would otherwise.

[SpeedyChix]

D had me set his up for snychro and adjust the number of cogs at the crossover. I hear it when the shift happens and while it works, I can't imagine using it. The shifts are so easy and quick I'd rather decide when/if I want to change rings up front. Although it's been awhile since I've been in hilly enough terrain to be doing that frequently.

On the plus side, with synchro it's still making the multiple cog changes but it does get it there w/o the accidental one too many cogs that can happen. With a Garmin screen setup you can set a field for to be an alert that the next shift will be the ring shift. As a couple others have noted, you can toggle through the three modes. The default setups for semi and full are logical.