Is there currently a known way to program/hack Shimano DI2 or Campy EPS so that it linearly steps thru each gear ratio instead of the user controlling the front and rear derailleur directly? Basically, adding a bit of logic to it. I would probably have the left two shift buttons move up in gear and the right buttons move down. With the inner buttons(thinking of Shimano) move a single gear and the outer buttons move in multi-shift. So nice although this is probably technically impossible due to mechanical limitations.

Personally, I like shifting to be as simple as possible and don't like thinking about when to move to the big ring, am I out of cogs on the rear cassette, which of these four buttons to press, etc. Part of the reason I currently ride a track bike for fun. However if this created a mechanical monstrosity even I wouldn't think it was worth it

doubt it since a few of the gears overlap so you have to decide what is best for the scenario. The only thing the DI2 buttons are doing is actuating a switch to move the derailleur.. it has no idea what gear it is in. if you ride enough you hardly think about it.

Fairwheel bikes hacked a Di2 setup on a mountain bike, with sequential shifting.

https://www.cyclingnews.com/features/...ipped-hardtail

You can easily program the sequence you want, decide when you're programming.

Pretty sure it knows what gear it's in, and transmits this information to flight deck.

It'd be trivial to implement with any sort of micro-controller.

ah.. i was wrong then. still stand by the end of it.. i barely think about shifting

Well I may be misunderstanding your direction but with the Dura Ace 9070 I can program any of the buttons to control up/dwn front or rear. I just went into the system to confirm but if I want the left shifter outer button to control front derailleur up and inner left button to do rear derailleur up then no problem.

On the multishift that is done as a complete set-up and not per button but frankly it's faster to tap the buttons per shift vs. the high speed multishift mode. In my case I have it programmed to keep the multishift so I can use it when I want.

Robby.. he wants it to be so that when he clicks down and is in 36-12 that the next shift will be to like 50-23 or something with one click... (i think)

now that's cool!

yeah thanks, now I get it. I was just looking at the semantics of button programming not the logic piece. That Fairwheel hack is pretty neat

Last time we went through this discussion, the objection was it would result in front shifts where you might not want them.

The rebuttal was that front shifting is so good with Di2 that's its not an issue.

Guess you'd have to ride with the setup to decide.

I can't imagine ever wanting a front shift when I didn't expect it. And no matter how good Di2 is, a front shift (especially in combination with a rear one) will never be as fast as a rear one. If you're grinding up a climb, do you really want to be flipping between ring and cogs at the same time? When cogs are already 2 teeth apart tops (most of the time only 1), is it really worth having the ring shift as well to find space in the middle? And this is going to make skipping gears intentionally a pain.

I have ridden Di2 and thought it was pretty slick. However, I didn't really care for it because I found myself missing the tactile feedback. Plus, mechanical systems allow you to control more precisely exactly when/how a shift occurs.

I have Di2 on two bikes. This sounds better in theory than it does in practice. I wouldn't want it. Most of the time when I'm shifting the front it's BETTER that it's a big jump, because I'm taking a quick grade change. I'd rather the one slightly bigger jump than have it shift the front/rear just to keep individual gear changes smaller.

What do you mean by this? Are you referring back to front shifting and finding the right gear?

The fairwheel bike seems pretty awesome, The main problem as stated in that interview is programming your shifters to sequentially shift. Unless you know how to write code really well you would end up spending hundreds/ thousands of dollars to pay a programer to write you a fast and clean patch. Its to new of territory to lightly delve into.

Not like DI2 is even remotely necessary, but this idea rides the niche train really hard.

I'm referring to either front or rear and in any gear. On mechanical systems, you can feel exactly where you are in the shifting process so you can make the shift occur precisely when you want to. With Di2, you press the button and there is a slight delay while the servo moves the derailleur. It's only a fraction of a second but it is noticeable and you can tell the difference. It's a different kind of ride and you can't feel your connection with the process like you can with mechanical. For this reason, I prefer mechanical even if Di2 is faster (particularly for shifting to bigger rings/cogs) if you measure the shifting process from start to finish.

I know a lot of people shift anywhere in the pedal stroke, but I think slamming thin chains under load is asking for trouble even if it works most of the time -- particularly when switching rings. So I always shift so the actual transition takes place as my feet hit the 6 and 12 o'clock positions. This means starting the shift a bit earlier and when/how you pull the levers is a function of what gear you're in and what gear you want to get to. I know the electronic system is less prone to user error, but I don't have problems shifting or finding optimal gears.