Jan Heine <heine94@earthlink.net> wrote:
<Snipped> One interesting factor among modern derailleurs is the weight difference among top-of-the-line derailleurs. Campagnolo's Record uses many carbon parts, yet it is heavier than the all-metal Dura-Ace and Sachs models.
Does the Campagnolo derailleur offer something the competition does not in terms of durability, better shifting or rebuildability? Or is it just a case of Campagnolo not pushing the envelope as far as the other companies?
Jan,
I think your example of the mostly-carbon Record weighing more than the alloy Dura Ace is telling. To be fair, I will say that I have neither ridden nor serviced a recent Record-equipped bike, but my gut reaction to the latest Campy stuff is that it contains lots of carbon for the sake of containing lots of carbon. In the last 20 years there have been virtually no enduring innovations brought to the table by Campy, save the predictable grafting on of that tenth cog. Their latest crank with the demi-axles is just a way of copying Shimano's design while making it just different enough to allow the pretense of superiority (a joint in the middle of the axle is better?). The campy cassette hubs were the same way, following Shimano's lead, and doing it in a slightly different way that was more complex and plainly inferior. So, the one area in which Campagnolo can claim to be leader is in materials. Never mind that, as evidenced by the respective parts weights, aluminum might be the superior materails choice. The benefit of CF is that it has associations with all that cool F-1 race car technology and the stuff can be visually distinguished from alloy from a mile away. I'm not saying that CF has no place on race bike components, I just think Campy is going nuts with the stuff becuase that's what is selling. CF front derailleur cages?!?!? Come on....
No, Campy is pushing the envelope all right, the marketing envelope.
Donald Gillies <gillies@cs.ubc.ca> wrote:
Gosh Tom, are you angling for a job at the Campagnolo marketing department *grin* ??
Well, you can tell by my comments above that I think they could use some help... in marketing, engineering, across the board.
Donald also wrote:
If you consider imho that the friction derailleur wasn't perfected until about 1975 or 1976 (I vote with Frank Berto for the Suntour Cyclone, but others may say it's Suntour Superbe), the indexed derailleur is still in its infancy and we won't see a really optimized indexed shifting derailleur until 50 more years have passed ... :-) :-)
To which I reply:
Cyclone and Superbe, are those my only choices?
But seriously, I take a very different view here. I don't see modern derailleurs as indexed derailleurs, but as an evolution of the same thing that's been evolving since the early 20th century. The first successful, modern indexed rear derailleur for racing was the 7400. It used the two-pivot design with offset body that Shimano had been pushinig for years, and combined it with the slated parallelogram that had been patented by Suntour. I have heard that Shimano added this "twist" as soon as Suntour's patent expired, but that is just hearsay. The resulting derailleur, the 7400, was so good that indexing actually was made possible. All the best indexing systems that have since come down the pike have used the two-pivot with offset body, and slant parallelogram features. The systems that haven't, notably Campy's pre 1990 stuff, didn't index very well. So, I think it was he evolution of the derailleur, a marriage of good design ideas, that made indexing work as well as it now does. The only design change that I see as uniquiely "indexed" is the floating upper pulley. I'm not sure, however, that it wouldn't provide benefit on a friction system. Which leads me to go out on a limb....
I haven't tried this yet, but I have to wonder if a modern top-tier Campy of Shimano rear der might be better than the best-ever friction derailleur (non-index compatible). My instinct is that it would be. After all, these are just evolutions of the same part. I can imagine a modern Dura Ace, perhaps mated to some Record Doppler retrofriction levers, shifting across a classic-spaced 6-speed freewheel with the right chain. One might need to futz with the pulleys to allow use of a chain wide enough for a classic-spaced freewheel, but it might all work better than even the venerable Cyclone.
To say that the indexed derailleur is in it's infancy disregards all the innovations from the friction era that it incorporates, and suggests that the designs are immature and ripe for revolutionary change. I sure hope not. The controls have clearly changed, form downtube friction, to clickers, to Ergo/STI. It is satid that soon it will all be electric. While I object to this on the notion that the bike should be 100% human powered, not reliant on even the smallest battery, there is probably nothing we can do. That said, from what I've seen, the electronic gizmos have similar layout and geometry to the current cable-driven stuff.
Kurt Sperry wrote:
The obvious first step is to stop trying to communicate the index detenting of the overall system via a thin flexible steel cable from the far end of the bike and put that function in its logical place near the cogs. I've never read The Dancing Chain but the idea is so intuitive, I'd expect it's been done before.
You make an excellent point. I think this communication is so tenuous that the direct cable path of STI, even though ugly, is clear benefit over the tortuous routing of Ergo cables. I'm also pretty sure that whatever mechanical detenting will be present on the electronic stuff will be at the derailleur. Systems with detents at the rear derialleur include the on-topic Positron (for sure) and the AX (I think).
Tom Dalton Bethlehem PA USA
>I think we should bear in mind that the task laid before a vintage
>derailleur such as a Jubilee, or even a Super Record, is quite
>different from that presented to a modern derailleur.
Your point is a very good one, and one that is easily overlooked. The Jubilee would not work with index shifting, and neither would the Campy Super Record.
Some of the old touring derailleurs, like the Cyclo or Nivex, probably could be designed to work with modern index shifting, as they are slightly early-shifting derailleurs. Some of these could be made from lighter materials (the Nivex is made from stamped low-grade steel!). The result might be lighter derailleurs than those currently available.
One interesting factor among modern derailleurs is the weight difference among top-of-the-line derailleurs. Campagnolo's Record uses many carbon parts, yet it is heavier than the all-metal Dura-Ace and Sachs models.
Does the Campagnolo derailleur offer something the competition does not in terms of durability, better shifting or rebuildability? Or is it just a case of Campagnolo not pushing the envelope as far as the other companies?
By the way, I do not believe that the difference between a Huret Jubilee and a Campagnolo Super Record (just 60 grams) will make a noticeable difference in the performance of the bike.
A full water bottle weighs 800 grams, and few riders notice their bike being faster when the water bottle is empty. (Of course, if they drank the water, they just have transferred the weight from the bike to the rider, at least until they sweat it out and it evaporates.)
That said, when given a choice, I'll take a lighter component over a heavier one any day, if the performance is similar.
Jan Heine Editor Bicycle Quarterly 140 Lakeside Ave #C Seattle WA 98122 http://www.bikequarterly.com
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