>
> > > Re electric shifting. I think this has the potential of increasing
> >reliability. Many electronic devices are far more reliable than their
> >mechanical counterparts....
>
> What you forget is that the shifting always will be mechanical. You
> need to move the chain from one cog to the next or find some other
> way to change the gear ratio. Electronics may be reliable, but their
> interface with the mechanical world requires motors, magnets or other
> electro-mechanical devices that have a propensity to fail.
I seem to recall that Mavic came out with an electronic shifting
system (something like a decade ago) that was prone to fail in the
field.
http://www.bikepro.com/products/rear_derailleurs/maviczap_rrder.shtml
Chip
--
Charles M. Coldwell, W1CMC
"Turn on, log in, tune out"
Somerville, Massachusetts, New England (FN42kj)
GPG ID: 852E052F
GPG FPR: 77E5 2B51 4907 F08A 7E92 DE80 AFA9 9A8F 852E 052F
On Sat, Mar 22, 2008 at 9:25 AM, Jan Heine <hei...@earthlink.net> wrote:
>
> > > Re electric shifting. I think this has the potential of increasing
> >reliability. Many electronic devices are far more reliable than their
> >mechanical counterparts....
>
> What you forget is that the shifting always will be mechanical. You
> need to move the chain from one cog to the next or find some other
> way to change the gear ratio. Electronics may be reliable, but their
> interface with the mechanical world requires motors, magnets or other
> electro-mechanical devices that have a propensity to fail.
>
> All you add is a layer of potential problems between the shift lever
> and the derailleur. The most reliable system is the old Campagnolo
> Cambio Corsa, where you derail the chain with a direct lever that
> attaches to a fork, which moves the chain... It is almost impossible
> to go wrong. Separating the derailleur from the lever and adding a
> cable already introduces a variable that can cause trouble (broken
> shifter cables, anyone?).
>
> Of course, most of us don't want to use a derailleur like the Cambio
> Corsa, where you open the rear quick release, backpedal, shift,
> gently pedal forward to get the chain tension loose enough and close
> the quick release. I've ridden a bike with that system, and it's not
> as bad as it sounds, but it would be cumbersome over the 1200 km of
> PBP. (Also, because all the chainslack is taken up by the wheel
> moving in the dropout slots, the gear range is very limited.)
>
> Reliability isn't everything, but it's important.
>
> Jan Heine
> Editor
> Bicycle Quarterly
> 140 Lakeside Ave #C
> Seattle WA 98122
> www.bikequarterly.com
> --
>
> >
>
--
I ride my bike, to ride my bike.
I have become so put off with the bike industry pushing "newer and better"
down our throats when they are the only benefactors. Put friction back on
your bike; you could even save almost a pound in weight ( for all you weight
weenies ) and ride worry free of having a bike fail during an event.
Russ
----- Original Message -----
From: "Jan Heine" <hei...@earthlink.net>
To: <ran...@googlegroups.com>
Sent: Sunday, March 23, 2008 10:45 AM
Subject: [Randon] Electric shifting, reliability
>
>>From: "Jim Bronson"
>>
>>What you fail to mention is that the electronic system has the
>>capability to eliminate the need for mecanical cables, which would be
>>an increase in reliability from my standpoint. If it wasn't for cable
>>stretch, we'd never have to fiddle with our derailleurs.
>>
>
> The problem you describe is not inherent with cables, but inherent
> with indexing in the shift levers. Moving the indexing to the
> derailleurs would solve the problem. The cables could stretch all
> they want, but the indexing adjustment would not change. However,
> indexing in the derailleur also would mean that you could use any
> shift lever. And Shimano invented indexed shifting specifically to
> make you buy a group, including their shift levers (and freewheel).
> Then they combined freewheel and hub into a cassette hub, so you had
> to buy their hub, too. Then they combined their brake and shift
> levers, so you had to buy their brakes, too. Then they combined their
> cranks and BB, so you had to buy the set as well.
>
> The obvious solution is to forego indexed shifting altogether and use
> friction shifting. I employ it on my bikes, and I don't ever worry
> about cable stretch, nor do I fiddle with my derailleurs. And I can
> combine any components I want (Maxi-Car hubs with Shimano freewheel,
> Huret derailleur, Simplex shift levers, Mafac brakes - no problem at
> all on my PBP bike).
>
> In addition, downtube shift levers give you a warning when the cable
> frays at the shift lever (where it usually frays) - the sharp ends
> poke your hands. (In case you ignore the warning, or the cable fails
> elsewhere, replacing a shifter cable in the field is easy with
> downtube shifters, too.)
>
> Finally, downtube shifters let you move your hands around every time
> you shift, thus preventing hand pain and numbness on long rides.
>
> Maybe, once all the problems with electronic shifting have been
> worked out, and the system works off my generator hub (I think
> Shimano is working on that, their latest generator hubs provide more
> power at low speeds to make this possible), I will consider it. Then
> I'd want voice activation, too. Just like I say on a tandem to warn
> my stoker: "Shift" and the new gear comes in. Based on my cadence,
> the system will know whether I want an upshift or downshift.
>
> In the mean time, the old Alex Singer will have to do.
From: many
To: ran...@googlegroups.com
Subject: [Randon] Electric shifting, reliability
>Shimano invented indexed shifting specifically to
>make you buy a group, including their shift levers (and freewheel).
>Then they combined freewheel and hub into a cassette hub, so you had
>to buy their hub, too. Then they combined their brake and shift
>levers, so you had to buy their brakes, too. Then they combined their
>cranks and BB, so you had to buy the set as well.
>The obvious solution is to forego indexed shifting altogether and use
>friction shifting.
Or simply twist the barrel adjuster while riding to achieve the same desired
result....
Shimano is in the bike business, and part of their appeal is their years
long struggle to outdo Campagnolo on the tech supremacy front, where Campy
set the standard so high for so many years with their beautiful, durable,
and precision adjusting bike parts like the bike world had not seen before.
Lots of good stuff has come out of this war, even down to when they 'make
you buy' a very inexpensive bike, which is miles ahead of an old Schwinn,
mainly because of many cool tech innovations which Shimano has been very
energetic about exploring and inventing over the years. It isn't a fair
statement to reduce Shimano's whole effort down to only attempting to
increase their market share, given that they have tried so hard for so long
to make good bikes.
For rando, I happen to like (need. Hmmm.) a wider range of gears than road
bikes typically feature, and nothing that isn't a complete and less
efficient copy even exists that is comparable to the Shimano 9-speed triple
crank + MTB rear derailleur/cassette set up for providing such a wide range
of gears on a road bike. Shimano really wins this one for me, and I'm glad
to have this set up. Plus, all the parts are readily available and mid-level
cost.
Wow, this discussion really has some life. Okay, enough defense of the
megatrons - Here's our rando reporter's photo set from the same morning,
with 2 photos of the Wegmann bike, finally put up on the red just as tribute
to this discussion. Ps. Thanks, Fabian.
http://www.flickr.com/photos/7398172@N05/sets/72157604217569579/
Regards!
Mike
As someone pointed out to me in a private email, the bigger problem is
cables sticking. That's what usually causes bad shifting and
necessitates replacment, for me. YMMV. OTOH, in general I am happy
with my shifting setup (indexed Campy barends) and it's fairly
reliable, right now being an exception as it's shifting like utter
crap and needs a new cable.
I am curious about the electronic shifters, no matter what anyone
says. If it improves reliability by an order of magnitude, then I
would be interested, but if it's technology for technology's sake then
I probably wouldn't be.
Then again, I have a Blackberry, cell phone and pager, 2 desktops and
a laptop (which I'm on now while watching the NCAA tournament in
glorious 1080i Hi def on my 56" LCOS RPTV while recovering into my
fleche). Suffice it to say I am into tech gadgets.
On Sun, Mar 23, 2008 at 9:45 AM, Jan Heine <hei...@earthlink.net> wrote:
>
> >From: "Jim Bronson"
> >
> >What you fail to mention is that the electronic system has the
> >capability to eliminate the need for mecanical cables, which would be
> >an increase in reliability from my standpoint. If it wasn't for cable
> >stretch, we'd never have to fiddle with our derailleurs.
> >
>
> The problem you describe is not inherent with cables, but inherent
> with indexing in the shift levers. Moving the indexing to the
> derailleurs would solve the problem. The cables could stretch all
> they want, but the indexing adjustment would not change. However,
> indexing in the derailleur also would mean that you could use any
> shift lever. And Shimano invented indexed shifting specifically to
> make you buy a group, including their shift levers (and freewheel).
> Then they combined freewheel and hub into a cassette hub, so you had
> to buy their hub, too. Then they combined their brake and shift
> levers, so you had to buy their brakes, too. Then they combined their
> cranks and BB, so you had to buy the set as well.
>
> The obvious solution is to forego indexed shifting altogether and use
--
>From: Jan H
>Sent: Monday, March 24, 2008 9:41 AM
>To: ran...@googlegroups.com
>Subject: [Randon] Electric shifting, reliability
>I want to clarify that I am not "anti-Shimano" in any way.
Jan,
We know. Your posts provide quite a bit of spine to this list and are always
greatly welcomed.
It's just that if we start the revolution by burning down the bicycle
factories, we are gonna need a lot more gas than we counted on, and it could
become problematic without the bikes.
Much prefer we start out at the Escalade factory....
Regards!
Mike
Did you go to NAHMBS looking for bargains?
> The obvious solution is to forego indexed shifting altogether and use
> friction shifting. I employ it on my bikes, and I don't ever worry
> about cable stretch, nor do I fiddle with my derailleurs. And I can
> combine any components I want (Maxi-Car hubs with Shimano freewheel,
> Huret derailleur, Simplex shift levers, Mafac brakes - no problem at
> all on my PBP bike).
I had cable stretch to drive a man mad on my first bike, a 1964 Dunelt
with Huret Allvit derailleurs (friction, of course). It seemed as
though I was adjusting the cable every few days. That simply doesn't
happen with modern cables, and if my experience is any guide, certainly
hasn't happened in the past 20 years.
But, looking at the other half of your statement: don't I recall
comments in a recent BQ regarding friction shifting components meant to
be indexed (such as hyperglide cassettes) suggesting drive trains meant
to be index-shifted worked better when index-shifted? My experience
friction-shifting a Hyperglide 8-spd were quite disappointing, with
ghost-shifts following every downshift at a traffic light. I find
friction shifting 7-spd Hyperglide to be much more satisfactory.
>
> In addition, downtube shift levers give you a warning when the cable
> frays at the shift lever (where it usually frays) - the sharp ends
> poke your hands. (In case you ignore the warning, or the cable fails
> elsewhere, replacing a shifter cable in the field is easy with
> downtube shifters, too.)
This is true for bar end shifters as well - the fingers being poked
part. I'm sure replacing downtube cables is easier than replacing bar
end shifter cables, although it's not like that's a really challenging task.
I have been using stem-mounted shifters for 15 years on my 1978 64cm Schwinn. I love the position and they shift the same today as they did when I bought the machine for $50.00 in 1993.
And for a really upright riding position, stem-mounted shifters (remember the 1970s?) make sense. I wouldn't do a brevet in bell-bottoms, though!
In other words, once you hit bottom it can't get any worse?
;-)
I've personally been handed my ass by Ted astride that very Schwinn.
I did not notice him having any difficulty shifting.
No doubt, but that's more a testament to Ted's skill than an endorsement
of Schwinn Approved Huret Allvit derailleurs, don't you think?
I think it's more an endorsement of my oft-repeated theory that the
heaviest and most performance-critical component of any bicycle is the
person sitting on it, and that quibbling over derailleurs is a waste
of bandwidth.
I don't think it's impossible to design an electrical or electronic shifting system for a bicycle that would be completely up to the test of a rainy 1200k. However, doing so would add a fair amount of excess weight, and would place further constraints on the battery design (either it would need to use AA's, or it would need to last a really, really long time between charges). Since this stuff starts out at the high end, those things aren't a concern. They obviously aren't for pro riders, but most non-pro riders with high end racing bikes don't give them that much punishment. I have a high end road bike, and that system would work just fine even for what I do with it (club rides and races, but not much in bad weather, and nothing very long).
My experience with electronics and electrical systems designed for bikes is that most really aren't designed for hard treatment. That's even true of the lights that are specifically marketed toward commuters. They're just not designed for a lot of bad weather. It's not that they couldn't be, but doing so would add some weight and some expense and so they don't do it.
In my opinion, the bigger issues where randonneurs are concerned are failure mode, user servicability, and field servicability. We're all willing to sacrifice some bomb-proofness in our tires for the sake of comfort and efficiency (exactly how much we will sacrifice has been debated here extensively!) because if we get a flat, it's not that big a deal to sit down and fix it. Most of us don't carry a spare derailleur cable, but if one brakes, we can generally find one and it's not so hard to replace. If we periodically check on that stuff, we notice it fraying before it brakes, and we fix it. Electrical shifting systems have parts that are harder to fix in the field, and the potential for software or circuitry problems that may not be user servicable at all (ever heard of rebooting your STI???).
All that being said, what's the worst that can happen? So one way or another, your shifting busts: a cable frays, the indexing gets gummed up, your STI lever stops working, a dog eats your shifter, your derailleur spontaneously combusts, whatever. What do you do? You can tighten the limit screws to hold the offending derailleur in place, and you have only the other one to shift with. If they both go, you do the same with both derailleurs, or shorten your chain and bypass them, and you have a singlespeed. It's inconvenient, and I bet you like shifting, but it's not the ride-ending disaster that busted brakes, wheels, frame, handlebars, seatpost, etc, would be.
So if you like a crazy modern shifting mechanism that's slightly less reliable than downtube friction shifters, it's not such an unreasonable choice to make.
Emily
> -------Original Message-------
> From: John McClellan <john-mc...@att.net>
> Subject: [Randon] Re: Electric shifting, reliability
One other thing you can do is pinch the end of the shifter cable in
place under a water bottle cage. That way, you can get the chain into
one of the middle sprockets (or even the largest). Using just the limit
screw, you'll still be stuck in a fairly small sprocket.
We were discussing the drivetrain on a 1970s vintage Schwinn, and I have
plenty of exposure to 1970s vintage Schwinn drive trains. My wife had a
1971 Schwinn SuperSport. It had an Ashtabula crankset and Schwinn
Approved Huret Allvit derailleurs. The most notable thing about its
shifting was an absolute refusal to complete a front shift under any
sort of load.
I owned a 1964 Dunelt with Huret Allvit. Unlike my wife's Schwinn, it
had a half-step crank, and shifted up front just wonderfully.
Or were you referring to some yet-to-be-released electric drivetrain?
--
Steve Palincsar
pali...@his.com
Alexandria, VA, USA
Not to mention a broken rider, as is more often the case.
- Bruce
jo...@johnandjuliet.com wrote:
> 1) Electronic shifting will not eliminate the need for adjustment as
> for the most part "cable stretch" is an ill-stated term as the cables
> don't stretch.. The housings wear in...
> Also a "perfect" system even after the housings wear in will still go
> out as the chain wears. The chain wears in more than one direction
> BTW... A) it gets "longer" and B) the side plates lose their
> stiffness... It is the loss of stiffness that will cause the
> problems. Unless the "computer" in the electronic shifters have a
> very complex feedback system to monitor the chain's position over the
> wear of the chain, pulleys, pins and springs of the system then the
> system will start to fail to shift crisply as it ages.
>
>
>
An electronic shifting device could be made self adjusting with no
knowledge of wear in the chain, pulleys, cables (assuming there still
are cables), varying spring tensions, etc. All the microprocessor needs
to"know" is when the chain is well centered on a cog (rear) and when it
is not.. This could be achieved by a feedback system which senses the
relative tension while shifting (shifting by feel) or by listening to
the vibrations while shifting (shifting by sound). There are many
examples of things that have been made more reliable with the use of
electronics.
Electronic fuel injection and electronic ignition has made automobiles
vastly more reliable than they were in the past. These are both also
electro/mechanical systems that have mechanical parts that wear out.
They also use feedback devices like knock sensors (feedback by
listening) which compensate for wear and variations in fuel etc.
Anyways this is not anything I feel very strongly about. I'm presently
using 10 speed non-indexed shifting with bar end shifters and am usually
quite happy with how they work.
Jacques