Classic Lightweights UK
Classic Components

Campagnolo gears

Rear 'prototype' Gran Sport and front Sport changer

Bates Campag 600

Here is a very nicely restored 1954 Bates Volante equipped with some very interesting components.  The gear changing is by courtesy of Campagnolo’s very rare early 1952 Gran Sport – the one with the drilled pulley wheels and extended cage which was only produced for a very short time.  The front changer is another rare piece, a Campag Sport with fore and aft moving lever. Chainset is a 47/50 Stronglight cottered steel.

Early-production Gran Sport

This is a first mass-production (1953) Gran Sport with cable adjuster which can be seen top-left  next to the 'throw' adjuster. This adjuster was dropped on later models.

Campagnolo Paris Roubaix gear

Campagnolo Paris Roubaix

Here is the rear end of a Bianchi Paris-Roubaix complete with the much coveted Campagnolo Paris-Roubaix  gear mechanism.   For those who are not familiar with the gear it works as follows:  the top of rear drop-outs are notched and these coincide with notches on the axle.  There is no chain tensioner at all – as the gear is changed the wheels walks backwards and forwards to keep the chain relatively tight.   How on earth does this work I hear you say.  As you can see, a rod goes up alongside the chainstay and has a lever at the top, not unlike a QR lever – which is appropriate as it happens. The gear is changed as follows:– First make sure that there is no one riding in front, or even worse, watching from behind.   Reach down to move the lever on its first part of travel which will then release the tension holding the wheel in the frame.  The next part of the lever travel moves the gear selection fork which can be seen astride the top of the chain.  Now pedal backwards (because the striker is on the top of the upper chain) whilst moving the lever to select a higher or lower gear.  If you select a lower gear then the wheel will have to ‘walk’ forward along the notches to accommodate the larger sprocket.  When this is done move the lever back to its original position to lock the wheel.  Breathe a sigh of relief and start pedalling in earnest again.   For a higher gear, that is to a smaller sprocket, the wheel will have to ‘walk’ backwards to take up the slack.   

Campag 3
Detail of the business end of the gear showing the serrated rear-end of the frame

You may have already guessed that I am an armchair expert as I have never ridden one of these gears but I suppose that goes for 99.9% of us.  The Paris-Roubaix gear was introduced in 1950. It superseded the even more complicated Cambio Corsa which had been available since 1946.  This gear worked on exactly the same principle as the P-R but had separate levers to release the hub and execute the change.   I think I am right in saying that a third version of the gear was produced where the striker operated on the lower chain and so obviated the need to pedal backwards whilst changing.  There is a cam on the gear which can be adjusted to pre-set the chain tension after the change is made. Peter Underwood

Frejus with Corsa gear

This is the earlier Campagnolo Corsa gear (on a Frejus Super Campionissimo 1949) which has separate levers, one to unlock the hub and the other to move the striker arm which is on the top run of the chain.  This still  entails the rider pedalling backwards for the change - so not the slickest change in the world.

This gear was patented  by Tullio Campagnolo in 1933.

Photo courtesy of Eric Sayliss