Pedal Backwards to Shift-The Cambio Corsa/Paris-Roubaix Thread

[Freqman1]

Since at least a few of us are interested in these I think we should have our own thread devoted to these shifting systems. The short story is these were developed before the war by Campagnolo although I question whether, other than a few prototypes, these actually went into production until after the war and more specifically about 1947. Cambio Corsa loosely translates to race gears and was also called the due leva (two lever) shifter. The Cambio Corsa drivetrain consisted of two levers, toothed dropouts and toothed gears on the axles. The Paris-Roubaix is so named because Fausto Coppi won the namesake race in 1950 using this system. The Paris-Roubaix or una leve (single lever) shifter combined the action of both levers into one with the addition of a locking gear at the bottom of the shifter. Notice the part that guides the chain to shift which I call a 'stirrup' is closed on the Cambio Corsa bikes and requires the chain to be broken in order to remove the bottom lever. The stirrup on the Paris-Roubaix is open at the top. These levers are not interchangeable between the two systems.

Cambio Corsa

Paris-Roubaix

How they work; the top lever is flipped out to release the hub in the dropouts. The teeth in the dropouts and the toothed gear on the axle kept the wheel aligned in the dropouts. The rider then pedals backwards and uses the second lever which has a stirrup around the chain and guides it on to the proper sprocket. The rider then has to lock the top lever back into position before pedaling forward. The Paris-Roubaix operates the same way. Even the top riders of the day that used this system didn't care for it too much and tried to limit shifting. If you try to pedal forward before locking the rear wheel at best you jump the chain and at worst you jerk the rear wheel out of the dropouts. This video shows how it works.

 

[dnc1]

Other names in Italian , more colloquial perhaps, for the 'Cambio Corsa' two lever system are:
"doppiasteccca" and "due stecche" both of which I've heard used recently.
A friend tells me that there were at least two different sets of the double lever system produced over time, a 'race' version and a 'touring' version; varying in length of operating rods; the touring version had longer rods I believe so it was technically easier to operate as you didn't have to reach quite as far to do so.
Does anyone have evidence of this, that shows the difference in lengths?

Here is probably the most famous photo of the system being used in real race conditions.
Gino Bartali, reaching down to change gear as he ascends the Col de Galibier on his way to victory in the 1948 Tour De France.....

...he is riding a 'Legnano' bicycle and his saddle is set relatively low to make gear changing less difficult.
I've lowered my saddle on the 'Cicli Vecchi' maybe 2 inches lower than I would normally have it, for precisely the same reason.

 

[juvela]

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mention of lowering the saddle height to make reaching the shift levers easier reminded me o' me first automobile

it was a Simca model 1204 of 1970 with an "H-pattern" manual four-speed transmission on the floor

in order to shift from second to third had to grasp the shift knob with fingertips only and extend right arm to its maximum reach forward and slightly to the right

am about 5' 9 1/2" in height with average proportions and could just barely make it; the "throw" was that long...

thanks very much for this description and the image of Gino


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[Freqman1]

Other names in Italian , more colloquial perhaps, for the 'Cambio Corsa' two lever system are:
"doppiasteccca" and "due stecche" both of which I've heard used recently.
A friend tells me that there were at least two different sets of the double lever system produced over time, a 'race' version and a 'touring' version; varying in length of operating rods; the touring version had longer rods I believe so it was technically easier to operate as you didn't have to reach quite as far to do so.
Does anyone have evidence of this, that shows the difference in lengths?

Here is probably the most famous photo of the system being used in real race conditions.
Gino Bartali, reaching down to change gear as he ascends the Col de Galibier on his way to victory in the 1948 Tour De France.....
View attachment 1559691

...he is riding a 'Legnano' bicycle and his saddle is set relatively low to make gear changing less difficult.
I've lowered my saddle on the 'Cicli Vecchi' maybe 2 inches lower than I would normally have it, for precisely the same reason.

I'd love to have a poster size of this pic. I have not seen Cambio bikes with different length levers and all of mine are the same. The Paris-Roubaix does have two different length levers. V/r Shawn

 

[Freqman1]

Short Paris Roubaix

Long Paris-Roubaix

Detail of Paris-Roubaix

Paris-Roubaix 'stirrup'--this is the part that guides the chain when shifting

 

[Freqman1]

Freewheels

Loose NOS

Freewheel on my Arbos (Cambio Corsa)

Freewheel on my Torpado (Paris-Roubaix)

 

[Freqman1]

I've noticed two styles of chain guards were used. I believe these were used interchangeably between the two systems as I have Cambio Corsa with both styles and my Paris-Roubaix equipped bikes are each different. I call these 'star' and 'spoke'.

'Star' Chain Guard

'Spoke' Chain Guard

 

[Freqman1]

My bikes--so far!
Arbos Corsa

Baldini

Bianchi Folgore (chain guard since removed and bike is being restored)

G. Fiori (on the way from Italy)

Legnano Tipo Roma

Torpado

 

[cyclingday]

Nice!

I have an original program/score sheet from the 1948 Tour de France.

 

[dnc1]

Other names in Italian , more colloquial perhaps, for the 'Cambio Corsa' two lever system are:
"doppiasteccca" and "due stecche" both of which I've heard used recently.
A friend tells me that there were at least two different sets of the double lever system produced over time, a 'race' version and a 'touring' version; varying in length of operating rods; the touring version had longer rods I believe so it was technically easier to operate as you didn't have to reach quite as far to do so.
Does anyone have evidence of this, that shows the difference in lengths?

Here is probably the most famous photo of the system being used in real race conditions.
Gino Bartali, reaching down to change gear as he ascends the Col de Galibier on his way to victory in the 1948 Tour De France.....
View attachment 1559691

...he is riding a 'Legnano' bicycle and his saddle is set relatively low to make gear changing less difficult.
I've lowered my saddle on the 'Cicli Vecchi' maybe 2 inches lower than I would normally have it, for precisely the same reason.

It would appear that my friend was incorrect re. the length of the operating rods.
Apparently the only difference in length relates to the parts of the levers that you handle whilst changing gear. The system came in 'Corsa' (short handles, for racing) or 'Sports' (long handles, for touring).
This is itself referenced in the 1953 catalogue, which states that "longer handles for touring are available on request", printed at the bottom of this image.....

...here is the 'Cambio Corsa' system as it appears in the 1953 catalogue.....

Tullio Campagnolo's French patent application drawings for the 'Cambio Corsa' system.....