On Sunday, November 24, 2019 at 5:50:31 AM UTC+1, Frank Krygowski wrote:
On Saturday, November 23, 2019 at 5:36:09 PM UTC-5, wrote:
On Saturday, November 23, 2019 at 10:58:13 PM UTC+1, Frank Krygowski wrote:
On Saturday, November 23, 2019 at 3:01:51 PM UTC-5, jbeattie wrote:
On Saturday, November 23, 2019 at 9:37:21 AM UTC-8, Frank Krygowski wrote:
In my view, putting immense complexity into a sealed black box
does not make a system "simple."

From a user standpoint, Di2 is very simple -- more simple than cables. No tension adjustment or lubrication, and no sticking after riding in muck. You have to charge it now and then -- and you can get fussy with programming (on bike, no computer necessary for certain settings). Electronic shifting is not an imperative, and it's expensive, but its a reasonable choice.

Well, sure, everything is a reasonable choice for someone in some situations.

But "no tension adjustment or lubrication"? I can't remember the last time I
did a so-called tension adjustment on anything but the folding bike; and for
whatever reason, that one seemed to settle down early this year. I think all
my shift cables are lined with plastic, but for whatever reason, I don't ever
seem to have to lubricate them. Well, except for where they pass through that
open plastic channel under the bottom bracket of one bike, and that's only
very rarely. Other lubrication? A Di2 derailleur still has mechanical pivoting
joints, doesn't it?

It's OK if someone wants to buy e-shifting. And given basic early adopter psychology, plus normal pride of ownership, it's a given that most who spend
many hundreds of dollars for its tiny benefits will say it's worth it..

But it seems obvious that 99.9999% of the world's cyclists - and even cycling
enthusiasts - get along just fine with mechanical systems. This choice proves
that, at best, bike technology is now way, way deep into diminishing returns.

And I really do think there's an important difference between "simple to use
because of incredible complexity built into a tiny box" and just plain "simple."
That difference shows up when something goes wrong.

- Frank Krygowski

What incredible complexity?

Lou

Upthread, I described the workings of a friction shifter in maybe 50 words or
so. Except for the design of the derailleur's mechanics (which is essentially
the same for both friction shifting and Di2) my description is very nearly
enough for a competent machinist to make a working system. It's that simple.

Can you do the same now for Di2? Don't omit a sufficiently thorough explanation
of the micro code and a description of the actuator in the derailleur. Describe
it well enough that someone can make one, plus program the code.

Why does anyone have to make one for their own. Shimano/Sram/Campagnolo did that for me.

Similarly, if you like we can compare descriptions of what to check if each
shifting system stops moving the derailleur. I know what to do if my rear
derailleur cable breaks and my bike is stuck in the smallest cog. Two times
(in 50+ years) I've fixed that on the road, far from home.

I don't make choices which if it went wrong isn't the end of the world or life threatening based on something that may happen once in 25 years. When it happens I deal with it. Probably I ride home or nearest bike shop in a not optimal gear like you wil do if a cable snapped and you don't carry a spare and/or the tools to replace it. Nobody carries a spare cable for their normal rides. Of coarse in this sort of discussions people are always far from home and in de middle of nowhere which they almost never do.

Tell us what you should do if your Di2 gets stuck in the smallest cog.

Like I said I deal with it like you have to deal with it. But I'm still waiting for 6 years now for that to happen with my Di2 system.

The comparison should show which is complex and which is not.

Why do all mechanical people get nervous when electronics are involved? In my line of work the mechanical parts are the least reliable not the circuit boards or the software once tested and debugged. Electronic shifting is not a complex system and not inherently unreliable. Don't compare a downtube friction shifter with Di2 shifting a 11-12 speed gear systems. That is another discussion. A simple motor and some switches replace all the mechanical parts within a STI shifter and a cable. Can you shift a 11 speed reliable with a downtube friction shifter by the way?

Lou