Mid-Life Cycling

Mid-Life Cycling

22 March 2016

The Flash Hub Is Gone--Or Perhaps It Never Came!

What is this?




No, it's not a vintage Campagnolo Record front hub retrofitted for disc brakes. (Oh, perish the thought!)  Instead, it's something I mentioned in an earlier post:





It's none other than the Cinelli Bivalent.  It may be the only hub in history that was designed to be used either on the front (as shown in the first photo) or the rear. 



The toothed wheel served no purpose on the front. On the rear, however, the gear cluster or cassette fit onto it.  This was supposed to make wheel removal and installation easier.  From what accounts I've heard and read, it seems to have fulfilled that purpose.



Being a Cinelli item, the quality was most likely excellent.  (Some have claimed that Campagnolo made the hubs for Cinelli.) When the system was introduced during the early 1960's, the hub had a three-piece shell, like most hubs of that time.  A few years later, Cinelli started to offer hubs with single-piece alloy shells.

Although it seems that those who tried the Bivalent liked it, the system never caught on.  The reason usually given is that racers didn't want to use it because if they had to replace a rear wheel, a support van or truck probably wouldn't have another on hand, and the threaded hubs (like Campagnolo's) almost everybody--including all racers--used at the time wouldn't work with it. 

(That, by the way, is also one of the reasons why Campagnolo Record (as well as Nuovo and Super Record) dominated the peloton for so long:  Everyone wanted equipment that was compatible with everyone else's.)

As I mentioned in my earlier post, during the ensuing two decades between the introduction of Bivalent and Shimano's Freehub system (the prototype of every cassette hub made today), there were other attempts to make something more convenient, versatile or stronger than the traditional threaded hub and screw-on freewheel--especially since manufacturers were adding more gears to bikes.  

One of those attempts was SunTour's UnitHub of 1969.  Like today's cassette hubs, it combined the gear carrier and hub into one unit.  From what few accounts I could find, it worked well and was sturdy. However, the public wasn't ready for it--just as it wasn't able to receive another SunTour debutante from that year, the Five-Speed Click indexed derailleur system.

A decade later, Maillard introduced their "Helicomatic" hub, featuring a bayonet-style mounting onto which a gear cluster mounted.  The idea was great (better, I believe, than the Freehub system or any of its descendants), but it was poorly-executed and thus prone to breakdowns.  Shimano brought out its Freehub around the same time and, as the saying goes, the rest is history.

But there was, apparently, an attempt to resurrect the idea of the Bivalent.  A company I had never heard of until I encountered it on Michael Sweatman's Disraeligears site made it--or, at least, made plans for it.  No one seems to know for sure whether any of those hubs were actually made.

The company, EGS, was based in France.  It made one of the most elegant or extravagant, depending on your point of view, and certainly most futuristic derailleurs ever created:  the UpCage.   In essence, it was a classic SunTour derailleur with its pulley cage mounted horizontally and a tensioning arm between the body and the pulley cage.  They weren't in production for very long, even though they were much loved by French downhill racers.

EGS UpCage.  From Disraeligears



Apparently, ESG had big plans:  its website--still up even though the company went belly-up in 2000--shows plans for a "Syncro-Shift" twist-grip control that operated both the front and rear derailleurs.  (Whenever I see any form of the word "Syncro" in a bicycle or component's name, I turn and ride as far and fast as I can from it!)  Also on EGS's drawing board were a brake system and something they called the "Flash Hub."

From the EGS website



ESG's website says the Flash Hub was to consist of a two-part hub, a fixed cassette mount and a moveable wheel mount.  The cassete mount unit was made to stay fixed to the frame's rear fork end.  I can't help but to notice their use of the term "fork end", which just may be a matter of translatation. Still, it leads me to wonder whether it would have worked with vertical dropouts.  No matter:  This system, according to ESG, would make it "child's play" to change the rear wheel.

There is no mention that the hub could be used on the front, so I imagine it wouldn't be possible.  To be fair, when Cinelli came out with the Bivalent hub, many frames made for derailleurs still had 110 mm spacing in the rear, as most freewheels still had no more than four gears.  Most road bikes then, as now, had 100mm spacing in the front fork.  So it probably was easier to make a hub that fit both front and rear than it would be to make such a hub now, when rear spacing is typically 130 or 135mm, and could grow if twelve or more gears and disc brakes become standard equipment.

Still, I have to wonder whether those guys at ESG--who, it seems, were downhill racers or had the attendant mentality-- knew about the Bivalent hub. 

N.B.:  Cinelli Bivalent photos were taken by Al Varick and appear on Classic Rendezvous.
 

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