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-bunch+unsubscr...@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.
