" that Libertas that (yes, Bill) I have plans to build" blah blah blah. I'll believe it when I see it.
BL in EC On Tuesday, March 19, 2024 at 1:56:11 PM UTC-7 Patrick Moore wrote: > Ah, I mispoke; Huret indeed. > > Peter knows much more about such pre-Campy parallelogram derailleur > esoterica, and I for one am glad I haven't had to get such a rd to work > since my 2-speed SA days, but I recall an old-timer on the CR list saying > that they worked pretty well if they were properly set up, but that setup > was very hard to do right. > > Peter, insofar as "low-normal" is the thread here and pullchain rds are > low-normal, have you set one of these up, and can we see photos? Maybe it > will give Grant some ideas. > > It has been years since I read Dancing Chain; was he really so dismissive? > I don't recall, but I'll have to borrow the book back from my brother. > > Also recall someone -- CR lister? -- describing how in the late '40s and > '50s in Australia race gearing was sparse (4 or 5 speeds), low (49 t sing > ring, 14-20 4-speed), and cadences high; and, shifted with pull chain rds, > the drivetrain often sounded like a coffee grinder -- I guess because it > was hard to adjust these things well. > > I'm tempted to hunt one down and install it on that Libertas that (yes, > Bill) I have plans to build up as a outside-lockable errand bike that is > fun to ride. With wingnuts. > > On Tue, Mar 19, 2024 at 11:57 AM Peter Adler <divis...@gmail.com> wrote: > >> And another nitpicky point: The two-lever derailleur is connected not to >> a Simplex pullchain derailleur, but to the mid-50s fancy-bikeshorts >> pullchain derailleur from their rival, Huret: the Huret Louison Bobet, so >> named for the three-time Tour de France winner (1953-55) whose Stella team >> rode with that derailleur. Simplex had a competing design - the Juy 543 >> named for the company president/designer Lucien Juy and the fact that the >> derailleur could be set with a slide mechanism to work with 3-speed, >> 4-speed and 5-speed freewheels, at a time when all were current in the >> marketplace. >> >> Like the Huret Louison Bobet, the Simplex Juy 543 had two cables. But >> instead of having a separate control lever for chain tension adjustment, >> the Simplex mechanism had a junction block which was clamped along the >> shift cable between the bottom bracket and the chainstay cable stop. The >> main pulley adjustment cable ran full from shift lever to derailleur, while >> a second cable stub was clamped to the first cable. The two adjustments >> this worked in parallel, which the chain tension automatically >> tightened/loosened as one shifted between bigger/smaller cogs. >> >> The Simplex was an early example of black-boxing tech; the pullchain and >> slide mechanism were concealed from view (and from road scuzz, which I'm >> sure was Simplex's excuse) with a chrome cover plate. It's a sleeker, more >> modern-looking derailleur than most pullchain models. >> >> All this engineering chozzerai must have been expensive to design and >> manufacture, and the price obviously discouraged mass appeal. My hunch is >> that the 1950s fixation on chain friction must also have been revealed to >> be silly. By the end of the decade, as Campagnolo was driving all the >> pullchain companies into irrelevancy in the racer market with a durable >> rear derailleur that as Frank Berto said, "didn't shift very well, but it >> would do it forever", and that didn't cater to the friction fixation at >> all. The ne plus ultra of Simplex's high-end pullchain derailleurs was the >> Juy 60, cosmetically a clone of the earlier 543 with the chrome cover >> plate, but with no freewheel selector (5-speed was assumed) and with no >> tension adjustment. After 1960, Simplex accepted that they'd lost the >> design war against Campagnolo's parallelogram derailleurs by building the >> excellent and beautiful Juy 61 Export (a design that clearly drove the >> designers at Suntour), and the technically similar/cosmetically uglier Raid >> 35, before going down the drain building derailleurs out of plastic. >> >> =============== >> >> Frank Berto's discussion of the history of the companies in the 1950s in >> The Dancing Chain is, IMHO, far better than his discussion of the >> derailleurs themselves. Hs take on all the 50s derailleurs other than >> Campy's Gran Sport is mostly to call the design stupid, which they sort of >> are. They're fiddly to get working; placing the pulley cage under the big >> cog is a real balancing act, because the placement is done by adjusting the >> tension on that coil spring inside the ribbon spring, which I only >> discovered a few days ago by accident. >> >> Berto's big objection is mostly to Simplex, who put the dual-spring cage >> in/cage out mechanism at the centerpoint of the pulley cage. Many of >> Huret's derailleurs put it close to the end, which means that one could >> route the chain like a modern derailleur for more chainwrap, with the >> pulley cage near the spring and the tension cage below. The Simplex ones >> work pretty much the same regardless of which way the cage is oriented, >> with no additional takeup. Berto's belief is/was that Simplex had made a >> nice livelihood for themselves making single-pulley derailleurs, and didn't >> want to alienate their racing customers by making derailleurs that worked >> wildly differently. So they made single-pulley derailleurs with two pulleys. >> >> Unfortunately for the hobbyist, Berto's contempt for the design means >> that he doesn't speak at all about making them work. 60+ years after they >> vanished from the marketplace, it's almost impossible to find any >> documentation on configuration, other than the original instructions >> included in the packages written in midcentury flowery French or English >> that's hard for most people (well, for me at least) to translate to >> instructions I can use. Most of the technicians who learned how to do it >> the official way BITD are now dead. Those of us who get them sorta-working >> mostly do so through dumb luck; my addition of a couple of extra links >> beyond the Shimano big-big +1 parallelogram measurement suddenly gained me >> the ability to reach 7 out of 10 gears, where I had only been able to do a >> single speed beforehand. A datapoint for the the tricks file. >> >> Peter "wall of text!" Adler >> Berkeley, California/USA >> >> On Tuesday, March 19, 2024 at 8:25:00 AM UTC-7 Patrick Moore wrote: >> >> BTW, Grant is wrong in the March 2022 blog about the second lever for the >> Simplex pullchain rd. It is indeed meant to take up or relax chain tension, >> but not because the derailleur didn't do that. The Simplex, like the >> Benelux, has a coil spring under that spiral ribbon spring -- both springs >> encircle a shaft over which the derailleur cage is pulled -- and the coil >> spring provides both in and out tension and cage tension (to put tension on >> the chain): you have to wind up the cage clockwise by not quite 360* when >> installing the chain, which is a real pain. >> >> The chain tension lever allowed you to fine tune this chain tension; in >> fact, to minimize it while still keeping enough so that the chain stayed on >> the chosen cog; this because, back then, at least some people thought that >> a tensioned chain caused a great deal of friction in the drivetrain. >> >> -- >> > You received this message because you are subscribed to the Google Groups >> "RBW Owners Bunch" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to rbw-owners-bun...@googlegroups.com. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/rbw-owners-bunch/396a9cad-43ea-4d7d-affe-d323292a6931n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/rbw-owners-bunch/396a9cad-43ea-4d7d-affe-d323292a6931n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > > Patrick Moore > Alburquerque, Nuevo Mexico, Etats Unis d'Amerique, Orbis Terrarum > > ------------------------------------------------------------------------------------------------------- > > Executive resumes, LinkedIn profiles, bios, letters, and other writing > services > > > ------------------------------------------------------------------------------------------------------- > > *When thou didst not, savage, k**now thine own meaning,* > > *But wouldst gabble like a** thing most brutish,* > > *I endowed thy purposes w**ith words that made them known.* > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. 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