[CR] 5 - 6 Speed Timeline,... and 7-8-9-10

(Example: Framebuilding:Paint)

From: "Bob Hanson" <theonetrueBob@webtv.net>
Date: Mon, 26 Jun 2006 02:50:43 -0600
To: classicrendezvous@bikelist.org
Subject: [CR] 5 - 6 Speed Timeline,... and 7-8-9-10


5 SPROCKETS:

"In 1936, Simplex introduced five-speed freewheels with thin 3/32-inch (2mm) sprockets." ~ [Berto, Shepherd & Henry, "The Dancing Chain" San Francisco, Van der Plas Publications, 2000, p.121]

"In 1936 Brampton introduced the 3/32-inch chain." ~ [F. Berto "The Dancing Chain, 2nd ed." San Francisco, Van Der Plas Publications, 2005, p.344]

--- However, I think these were seldom seen on Racing bikes for a great many years. I suspect it was likely the French "Constructeurs" who may have made use of this technology early on - and primarily to the benefit of Cyclotourists.

6 SPROCKETS: 1960 -- Regina [shown in "Le Monde de Daniel Rebour", p.175]. The illustration shows a 13-24t freewheel. I'll bet THIS was the one Campagnolo had in mind with the 1961 Gran Sport derailleur modification which Mark Bulgier pointed out. 1963 -- Cyclo 1965 -- Huret

{The following data, again, is all from "The Dancing chain"}

7 SPROCKETS: SunTour-- 1980 Shimano 1981 Campy -- 1987 Sachs/Huret -- 1988

8 SPROCKETS: Shimano -- 1989 Campagnolo -- 1991 Sachs-Huret -- 1991 SunTour -- 1992

9 SPROCKETS: Campagnolo -- 1997 Shimano -- 1997

10 SPROCKETS: Campagnolo -- 2000 Shimano -- 2004

As Mark and others have commented, the Pro teams were using 6-spd freewheels during the 1960s, but I too never saw one in general usage until the mid 1970s.

One problem with early 6-speed freewheels was the width of the chains. Early 6-spds still used the same older chains with 9mm pin width. So, I think the frames of racing teams had to be nudged out a bit more than 120mm.

ALSO, those chains didn't bend much laterally. I imagine the average recreational rider would have had to be a lot more attentive and adept at his friction shifting in spite of decent available 1960s derailleurs which could handle the extra gear (like the moderate priced Huret Allvit). So, maybe not a good thing to spring on the general public. Plus, there was not a big "adult bike" market in the US during the mid '60s, anyway. Probably no surprise that I didn't see 6-spd derailleurs until after the big American Bike Boom of the early 1970s.

In 1976 Shimano introduced Uniglide chains with outer plates bulged to the width of the pins. This improved shifting, but freewheels required the same spacing between cogs as a 5-spd. In 1977 Suntour made their narrower "Ultra" chain for 'compact' freewheels which squeezed 6 cogs into 120mm spacing... but then shifting got worse. In 1980 Sedis (France) brought out the Sedisport chain with both a bulged "inner" plate to improve shifting and with the first patented "bushingless" design - for improved lateral flex. This greatly improved shifting. All modern narrow chains are now bushingless.

I don't think derailleurs have changed much over the last 20 years, but chains have successfully narrowed and tooth profiling has improved shifting in spite of narrowed sprocket spacing.

So, NOW I can have far more gears than I will ever need and I can index shift through them all as fast and effortlessly as Lance Armstrong. And, my new components will be obsolete next year. Progress.

[Sedis chains became Sachs and are now SRAM.]

Bob Hanson, New Mexico, USA

Mark Bulgier wrote: Also, from Chuck Schmidt's Campy timeline:

"1961 -- In July a revised Gran Sport rear derailleur is introduced With a 10mm spring cover (was 8mm) to improve shifting on six-speed freewheels."

Donald Dundee wrote: According to "Le Monde De Daniel Rebour", page 176, there is a Cyclo freewheel (French) six speed freewheel dated 1963.

Hilary Stone wrote: As far as I am aware the first production bike with a six-speed Freewheel was the Moulton Speed Six in 1964/5. Although not common it was a genuine catalogued production machine built in reasonable numbers. It used a special freewheel with small top sprockets and a modified Cyclo Benelux P60 rear derailleur (modified by Cyclo not Moulton).

Pete Geurds wrote: Thanks for the catalog pages. I was surprised to see a 13-26 six speed Regina freewheel in 1964(?) Was this intended for touring and would it have required 126 spacing?

Chuck Schmidt wrote: Good question! This always puzzled me. In the mid-1950s the racing bikes came with 4-speed freewheels, even though there were 5-speed freewheels available. In the mid-1960s the bikes came with 5-speed freewheels even though there were 6-speed freewheels available. I have heard that the early 70s Raleigh Professional was the first production bike that came with a 6-speed freewheel (Atom) and I don't think 6-speed freewheels were generally in use until the mid-1970s.

Seems like there was a ten year lag each time before anyone decided they really needed another gear. Quite a contrast to today's drivetrains with the number of speeds in the rear increasing every couple of years.