Note that in this thread Jim and Jan use the common term "cable stretch" for the phenomena that really should be more accurately identified as "cable housing compression." You can read the full thread here but I've quoted Jan Heine as he makes the case thusly:
From: Jan Heine
Date:
To: randon@googlegroups.com
From: "Jim Bronson"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.
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 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.
Jan Heine
Editor
Bicycle Quarterly
140 Lakeside Ave #C
Seattle WA 98122
www.bikequarterly.com
---------------------------
From: Russ Loomis
Date:
To: randon@googlegroups.com, Jan Heine
Bravo!!! Jan Heine! I could not have said it better myself. I also use down tube friction shifters on all my bikes ( after having tried STI for over 5 years ) and thus eliminated all the shifting problems of index shifting. They are cheap, reliable, and last a lifetime but the best feature is that I can use any cassette or freewheel combination from 5 spd - 10 spd. It also puts the riding experience back into riding. Like driving a stick instead of an automatic. Fun.
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
Interesting post, but I think it makes a better argument for more compatibility among components than about the merits of downtube shifters. No doubt some proponents of the tried and true highwheeler were lamenting the new fangled safety bicycle's arrival on the scene. Lately, with SRAM introducing shimano compatible components, I think we all benefit. Components are interchangeable as long as you stick within one of the the 8, 9, or 10 speed drivetrain choices. Looking at my bike right now: SRM crank, shimano shifters, SRAM cassette. No downtube shifters in sight.
ReplyDeleteI don't dispute your preference for a second, and can see the advantages. At the same time, you can have my indexed shifters when you pry them from my etc. I gave up cycling 20 years ago, and restarted 7 years ago based almost entirely on the ease that indexed shifting offers. And I say this even though I'm one of those people who can replumb a kitchen or build a PC from scratch, but can't adjust my gears worth a damn!
ReplyDeleteI'm a friction guy. I don't have any trouble adjusting indexed shifting, but I prefer to have shifters that require no adjustment and can adapt to a wide variety of component mixes (parts tend to move around on my bikes). I like downtube shifters for various reasons, but mostly I run bar-ends or thumb shifters.
ReplyDeleteHere's something that has been blowing my mind for a couple years. Shimano still makes Dura-Ace downtube shifters, and I have used them and like them. The mind-blowing part is that they make them indexed for 9sp and for 10sp, but not 7/8sp. How many riders who have adopted 10sp are using downtube shifters?
I've said it for years: real men don't need index. I must admit, though, that my Raleigh three speed and my SRAM 7 speed internal are indexed. Run what you like, but friction is the ultimate in relaibility. Val
ReplyDeleteThree comments:
ReplyDelete#1: I don't grok all the bias against indexing. Maybe I'm just lucky, but all of my bikes are indexed in one way or another (barcons being the most common style) and I've never had a reliability problem nor do I have to fidget with their adjustment more than a few times per year. They just *work*...and isn't that the point?
#2a: Jan argues that locating the indexing mechanism in the shifter vs. the derailleur was a way for Shimano to monopolize the industry. Now that virtually nobody makes a friction shifter and many competitors have cloned their indexing, they could actually flip-flop and regain that monopoly.
#2b: Jan also forgets the original Shimano Positron II shifting, which used a finicky push-pull cable and had the indexing points in the derailleur. That was never a high-end system so perhaps it doesn't count. I dunno.
1x/3x/5x/7x/8x/9/10x friction or index or electric-zappy...Who cares? Just ride bike!
"How many riders who have adopted 10sp are using downtube shifters?"
ReplyDeleteAt least one: me. I've got them and I love them.
As for the lack of maintenance argument, I think this is way over blown. Indexed systems require little in the way of maintenance and are very easy to adjust if you're mechanically competent. If people are so concerned with maintenance why don't these same people run solid tires. Imagine never having to worry about pumping tires or getting a flat! That's so much better than them pesky pneumatic tubes.
(I originally sent this to Jim as an offline response)
ReplyDelete9/10s on the downtube? My next machine will have it. I'd use downtube shifters on my current "modern" bikes if the frames had come with bosses for them. My wife won't ride a bike with STI/bar-cons either, but she likes gears and prefers indexed shifting, so her machines get 9s downtube shifters.
I suspect the market is quite small for downtube shifters right now, despite the (small-ish) weight and reliability advantages to them (I dislike STI's ergonomics, but Ergo works fine for me).
With non-racing bikes getting more fashionable, I suspect the market for DT shifters will grow, and Shimano is the only indexed game in town unless you are handy with sheet aluminum and a file. Campy 10s bar-ends can be modified to mount on DT bosses, but it requires downtube shift lever stop fabrication. Shimano DT shifters also have a friction setting for wheel/cassette emergencies. They really are sharks in the modern bike world.
I’d be surprised if they sell too terribly many of them compared to STI, but I am sure glad they still make them. Now, if only bicycle manufacturers still routinely specified downtube shifter bosses....
Best Regards,
Will
@jim: Down tube shifters are still used on the aero bars of some triathlon and time trial bikes.
ReplyDeletewww.trivillage.com/prosft0100.html?productid=prosft0100&channelid=FROOG
Personally I've never had any issues with indexed shifting. I adjust it maybe once a year. Electronic shifting looks like a disaster though. In my world, if a battery needs to be re-charged, it probably won't be.
This is one of those religious arguments and everyone is correct. Over the years I have run both and honestly I think the problems have been about equal between the two. The main problem I have had over the years has been cables guess what both systems use cables. By high quality cables keep'em clean and lubed minimizes the problems with either setup. I hear the argument well you can't find parts in the middle of nowhere for index shifters but given the prevalence of index shifted bikes on the market I find that hard to believe.
ReplyDeletei roll fancy ratcheting bar-cons. friction only. they work very well: once a month all the bumps will slightly loosen one, requiring a slight turn of the nut.
ReplyDeletemy other bike, an old bridgestone MB-4 i found in a ditch, rolls the original deore thumbies. ii have them set to friction, because guess what, they're meant for 7sp but i have a 9sp wheel. in friction, i've got zero problems or issues.
the main barrier between me and STI style levers in cost. even cheap ones are expensive. i also think they're ugly.
Well I agree that the trouble keeping index shifting bikes running smoothly baffles me. There are only a few variables to deal with and once you have a bike dialed it should only take an occasional tweak to keep it shifting great.
ReplyDeleteIf you want to go friction shifting it works well, but don't use the fancy ramped and pinned cogs or you'll have trouble getting the shifts dial due to poor feedback.
I just switched my city bike over from SIS to a pair of old Suntour Power Barcons. Much, much nicer. We also own road bikes with Ergo-10 and (retro)friction/downtube shifting. I have no problem with the Ergo setup, it works fine, but so far as I can tell, indexing adds no functionality whatsoever. Ergo/STI does impose unnecessary penalties in weight and mechanical complexity.
ReplyDeleteHarumph.
STIs\Ergos are a very complicated and expensive way of moving a chain from one sprocket to another.
ReplyDeleteThey offer a nice and convenient solution but at quite a cost.
DT shifters require a little more effort, however they have very little cable friction to contend with. I prefer the simplicity over the convenience.
I used to love STIs but now prefer the clean lines and simplicity of a widely spaced DT setup.