The Simplex Route from the early 1930s, with its two giant pulley wheels, looked like a fossil birthed in the primordial slime of derailleur evolution. The product of hunched, slightly crazed, inventors obsessively fettling in their chaotic, chilly and ill-lit workshops.
Then, in 1936, Simplex introduced the Simplex Route Léger. This shared many of the key parts of the previous year's version of the Simplex Route, but it looked and felt quite different. Suddenly we had left the lunatic fringe and moved decisively towards the 1950s world of mass-produced derailleurs that were mainstream consumer products. The Simplex Route Léger defined the look of Simplex touring derailleurs until 1960.
The big change came in the pulleys and pulley cages. In the mid-1930s a number of derailleur manufacturers, including Simplex, moved away from the 'old' way of big, 14+ toothed, guide pulleys and large flanged tension pulleys mounted on substantial steel arms. Instead they adopted the 'new' way of small, often untoothed, guide and tension pulleys mounted on rather more delicate steel or aluminium arms, which also carried refined pusher plates surrounding the guide pulley. The 'new' way was significantly lighter than the 'old' way - and the derailleurs seemed to shift just as well (or, in modern terms, just as badly).
This is Simplex, so the timeline of different variants is messy and complex. I guess that it goes something like this:
- I think the very first Route Léger dated from 1936. I also think it had a one-piece bronze casting holding the bell-crank and an 80mm pulley cage with a one piece pusher plate at the guide pulley. This pusher plate was made of a single folded steel plate. The chain tension spring attached to a distinctive folded hook on the outer pusher plate.
- Then, perhaps in 1937, the design was improved to have seperate pusher plates either side of the guide pulley, joined by two struts.
- For 1938 I believe that the complex bronze casting that held the bell-crank was replaced with a simple cylinder with a steel band around it. The attachment point on the pulley cage for the chain tension spring was also simplified to be a small tab with a hole in it.
- Also in 1938 Simplex launched a very different design, possibly called 'Route Extra Léger'. This had no pusher plate, but instead used a toothed pulley. This used the new cylinder-and-steel-band arrangement to hold the bell crank. Crucially the main cylinder was aluminium, although the pulley cage arm was 72mm long and steel. This is a truly odd and out of trend design.
- 1938 was a busy year. It is possible that later in the year the 'Route Extra Léger' was replaced by the even more aluminium 'Route Extra Léger Type Grand Prix Duralumin'. This has pusher plates and an aluminium pulley cage arm. This was possibly 80mm long. Why it needed quite so many names is unclear.
- By 1939 there were three models, the Route Léger (as 1938), the Route Extra Léger Type Grand Prix Duralumin (also as 1938) and the new Route Extra Léger Luxe which was an aluminium model priced between the other two. What differentiated the two aluminium models is not clear to me.
- Sometime around 1940 the pulley cage was shortened to 65mm and the method of attaching the chain tension spring to the pulley cage was 'improved' again. This time the spring hooked into an curved, articulating, lever that attached to the outer pusher plate. These changes were made to both the Route Léger and the Route Extra Léger Type Grand Prix Duralumin. It's possible that the Route Extra Léger Luxe had disappeared by this point.
- During the Second World War, or perhaps in the chaotic years immediately after the liberation of France, a shortage of nickel and chromium let to the creation of a steel, but all black, Route Léger.
- Perhaps in 1947 the Route Extra Léger Type Grand Prix Duralumin and the Route Leger were replaced by the, rather similar, Simplex Grand Tourisme.
I think that this is an example of a Simplex Route Léger from about 1941, with an aluminium 'brasé réglable' mount that bolts onto a brazed on plate under the chainstay. I believe that it is finished in black due to wartime shortages of Nickel and Chromium. Some of its features are:
- The component holding the bell crank is a simple, 18mm diameter, cylinder with a steel band around it. It has a branded protective/decorative cap.
- The cable is clamped at the bell-crank using a grub screw.
- The guide pulley has a separate pusher plate on each side, joined by struts. These pusher plates cover an arc of about 180 degrees.
- There is a pivoting lever attached to the outer pulley cage plate to accept the chain tension spring.
- The pulley cage arm is 65mm long.
- The writing on the pulley cage arm is 'SIMPLEX MADE IN FRANCE'.
- The pulleys are black and were originally round.
- Derailleur brands: Simplex
- Categories: Simplex - before 1945
- Country: France
- Date of introduction: 1941?
- Date of this example: unknown
- Model no.: unknown
- Weight: 223g excluding the mounting bolts and the chain tension spring.
- Maximum cog: unknown but large
- Total capacity: unknown but large
- Pulley centre to centre: 65mm
- Index compatibility: friction
- Chain width: 1/8”
- Logic: top normal
- B pivot: none
- P pivot: sprung
- Materials: steel with white metal bell-crank and aluminium mounting plate
Ref. 995
