The beauty of the bicycle (as opposed to the motorcycle, the electric scooter, etc.) is that it is simple, mechanical, and human-powered. Though electronic shifting doesn't propel the bike forward, it does replace a function done by humans (the tightening and loosening of cables) with one done by batteries. Unlike computers, lights, power meters, etc., Di2 renders the bike unrideable without these batteries. That ain't good.

Don't bother accusing me of being a technophobe or anti-innovation. I love bicycle technology, and I'm as excited as anyone else when it comes to things like aero tubing, carbon parts, ceramic bearings, bla bla bla.

It seems odd to me that the UCI, in order to keep costs down and improve safety, sets all sorts of regulations regarding bike weight, tubing type, brake placement, etc. But when Shimano decides to overhaul the entire drivetrain system by adding a battery, nobody seems to care.

Opinions? For or against Di2?

Now if you want simplicity then I agree with you. From a performance standpoint no.

As for the UCI regs, think of those template rules for NASCAR for car design, there needs to be a level playing field.

I realize that Di2 performs amazingly well (many people have told me). Performance aside, do you think this is a good direction for the sport to be moving...?

Before you start bashing Di2, have you ridden it? I too was skeptical at first, until I rode it.

What you are saying is lets go back to cars with carburetors, no power steering, no power brakes, no ABS, no traction control, because it takes away from the driving experience

I specifically pointed out that I'm not opposed to technology. I like it.

I also pointed out that I'm not talking about "performance." I realize that Di2 shifts amazingly. I also realize that a motorcycle goes really fast. That's not the issue. The issue is whether or not a non human-powered device belongs on a racing bicycle.

I specifically pointed out that I'm not opposed to technology. I like it.

I also pointed out that I'm not talking about "performance." I realize that Di2 shifts amazingly. I also realize that a motorcycle goes really fast. That's not the issue. The issue is whether or not a non human-powered device belongs on a racing bicycle.

I'm not opposed although I doubt I'll ever buy it. I don't see what the concern is. If it's cost, that is nothing compared to the wind tunnel testing, bike fitting, tire development costs going into racing.
Electronic shifiting is something some of the club/racers can actually buy and use. I just hope development of non-electric components continues.

From a purely subjective viewpoint, I'd say no.

I can't say it's really a big deal, though. Or that UCI should even really listen to me.

Electro-mechanical systems can OFTEN be less complex, more reliable and lighter than purely mechanical systems.

If you think about it, on DI2 you have a battery, two servos, a few buttons and some wires. As far as electronics go, the system is less sophisticated than many watches or cyclometers.

Traditional integrated shifting has:

A pair of fairly complex (expensive!) indexed shifters, one with ghost clicks to trim out chain rub.
A cable system that needs to be changed periodically due to reduce friction due to contamination.
Cable adjusters to take up cable tension.
Pinch bolts which also adjust cable tension.
High and low limit stops on each derailleur.

The derailleurs themselves as well as how they're fixed to the bike are essentially the same in both cases.

Mechanically, there's more to go wrong with the traditional drivetrain. Yes, they are very, VERY well refined. Generally not the source of problems on a correctly set-up bike with decent quality components.

That being said, electrical systems can be FAR more reliable than practically any mechanical system. Computers can perform billions of operations per second for YEARS without any errors. I defy you to find a mechanical system with that kind of reliability. A hammer doesn't last for that many cycles.

If there are reliability problems with DI2, it would be one of implementation, not fundamental to it's electro-mechanical nature. That being said, I haven't heard of problems like that cropping up yet.

Performance, by many accounts is excellent. I haven't heard of many people saying it performs WORSE than traditional DA. Only people saying it's not worth it at the current price.

Grumbling about price can be done about any level component from Sora through DA, it all depends on how much money you have and how sensitive you are to price.

As for is it a direction the bike industry should go in: If it results in simpler, more reliable, higher performance, simpler and eventually cheaper components, why not? Let the market decide.

It's certainly not giving a bigger performance delta than integrated over non-integrated shifters, or clipless over toe clips, or carbon aero over traditional box rims. All of those entailed cost increases.

My opinion is that this is silly. It replaces an action performed by humans? Uh, okay, sure. Consider what you're doing when you tighten one of those cables (aided, of course, by the indexing detents built into your shifter that ensure you move the cable just the right amount). You are transmitting positional data to your derailer. The difference with electronic shifting is that this information is transmitted in the form of bits rather than cable tension.

As for the batteries running out, it's no different than breaking a cable on conventional cable-pulled systems (hey, remember how that CAN happen??). Actually, it's better, since the system gives you plenty of warning, which you can use to put it in a gear that you can ride the rest of the way, unlike a broken cable which typically happens with no warning and dumps you into the highest cog on your cassette or the small ring on your crank.

Saying that you like bicycle technology but not THIS technology doesn't make me think you have a point, it makes me think that you're an irrational hypocrite (no offense or anything). There was a big deal made about the adoption of gear-shifting mechanisms; in spite of that being a far bigger deal than changing the means used to shift gears, cycling got through it. Similarly, some raised a stink about indexed shifting, arguably also a bigger deal, certainly at least equal. Again, no one's making that argument now. But riding around on a ten or eleven-speed bike with indexed shifting controlled from integrated brake/shifters and then complaining about how electronic shifting will undermine the integrity of the sport strikes me as a complete failure of self-awareness.

As a vintage rider with DT shifters on a majority of my bikes, Ergo on just one, and have never even been in the saddle of a plastic bike, NO, I'm not opposed.

Back then I was able to fix my cars with tools from my home workshop. Now most need complex and expensive tools/computers.

If the Di2 parts are so simple then they should cost no more than the mechanical version of the same parts, yet they are priced many times as much. I think something is missing in that analysis. The FD and RD may look simple from the outside, but have you ever taken one apart to see what's inside?

I can outfit at least three bikes with high level Campy 11 for the price of one Di2 conversion. Campy 11 speed brake/shift levers, for example, start at $180 and go up to $320. Compare that to Di2 brake/shift levers.

I've got nothing against it, but the price is just too high.

I have no opposition to Di, I just don't think its really any great innovation. The limitations of any derailleur system is the fact that the chain has to be pushed to another cog or chainring. The limiting factor on speed of shifts is the cadence you are pedalling at and the torque you are exerting at the time you shift. Di still has that limitation. Mechanical systems are extremely precise, fast and reliable, I don't see Di as improving on anything major.

I understand your point, and it's a good one. But it seems to me that previous big innovations were qualitatively different from Di2. The freewheel, the derailleur, index shifting, clipless pedals, etc - there were mechanical improvements, and still relied on human power. With Di2, we're moving away from human power. Your point that with electronic shifting "information is transmitted in the form of bits rather than cable tension," seems hollow. You could apply the same principal, if taken to its logical end, to electronic pedaling.

I feel the need to repeat: I am not a technophobe, and I don't choose to arbitrarily (and hypocritically) draw the line of technological acceptability at electronic shifting. On the contrary - Di2 seems to be an interesting (even amazing) technology, and if folks want to use it to get around town, great. I simply think that, for the purpose of racing, Di2 fundamentally changes the definition of what a bicycle is (a purely human powered machine), and should therefore be rejected.

And they break far less often; a point that is often overlooked when grumbling about this.

I understand your point, and it's a good one. But it seems to me that previous big innovations were qualitatively different from Di2. The freewheel, the derailleur, index shifting, clipless pedals, etc - there were mechanical improvements, and still relied on human power. With Di2, we're moving away from human power. Your point that with electronic shifting "information is transmitted in the form of bits rather than cable tension," seems hollow. You could apply the same principal, if taken to its logical end, to electronic pedaling.

I feel the need to repeat: I am not a technophobe, and I don't choose to arbitrarily (and hypocritically) draw the line of technological acceptability at electronic shifting. On the contrary - Di2 seems to be an interesting (even amazing) technology, and if folks want to use it to get around town, great. I simply think that, for the purpose of racing, Di2 fundamentally changes the definition of what a bicycle is (a purely human powered machine), and should therefore be rejected.

Bike racers still win races. You want to lament something in racing? Lament doping.

It's still a human-powered machine, at least as far as propelling yourself forward. There's no forward motion assist. Shift Di2 alll you want, bike's still not going anywhere until the human pedals.

I'm opposed to the price......

Coolness factor of Di2 is awesome and it shifts great but so does Sram Red, Force and Rival, Shimano 7800 and Campy. It just doesn't seem worth the upcharge at this point with it weighing more as well. Totally cool idea but aesthetically, I hate the look of the battery pack too.

True. But what do I know, I still ride steel...

Oh, but it IS arbitrary and hypocritical. Saying that it isn't doesn't get you off the hook. This idea that electronic shifting changes the fundamental nature of the bicycle needs to be examined. How does electronic shifting change a bike from human-powered to partially not human-powered? Does shifting propel the bicycle forward? Does shifting require some degree of athleticism that would be compromised by making it electronic? Duh, no. We've been trying to make shifting gears easier and easier for decades, and suddenly this is going too far? You're really caught up in this idea of "human-powered" shifting, and it's silly.

I really don't see what's different about the effort involved in shifting electronically. The important thing with any shifting system is, again, that you are transmitting data to the shifting mechanism. Last I checked we weren't shifting with our minds alone; you still need to move your fingers and press a button. The difference with electronic shifting is that you don't need to move the lever as far, but that's it. The data is just sent as bits instead of millipascals or whatever. So, yes, the idea that electronic shifting makes the bicycle less human-powered is indeed arbitrary and laughable. Shifting does not propel the bicycle forward. Very little is really changing here in terms of how we interact with bicycles.

Nothing much to add to this discussion except to reiterate it is usable if the battery dies, and the crash feature would actually let you hand move the RD up to a specific cog. You also only lose the front shifting first (or was it rear?) at critical battery levels. Anyway, after riding it and feeling it with Shimano reps, the battery life is so long and there is advanced warning that you would have to be an idiot to have the battery die on you. Basically you would need to leave for your ride with the system telling you the battery is very low, which it also told you at the end of the last ride. I was impressed.

Now, I'm a Campy guy. What I want to see is the Campy electronic set. First to market has advantages, but so does waiting to see the competition first to make revisions. Hopefully Campy will take some notes and add both 11 speed and Italian aesthetics.

Electronic shifting seems like a cool idea as long as the shifting is done manually, but if they turn it into an "automatic" shifter, then they will be going too far. It is the same with cars, I have both automatic and manual shift cars, but I prefer a manual. There are already "automatic" shifting coaster and crusing bikes, so it is not a stretch that we could find automatic shifting on road bikes at some point.