Wanted Urgently – Maxi Tandem rear drum brake (tambour) Super Grand Tourisme 115mm, alloy flanges and 40 holes

I am in need of a Maxi Tandem rear drum brake (tambour) Super Grand Tourisme, 115mm, duralumin flanges and 40 holes, in good usable condition, for the René Herse tandem featured in the next post. The steel version is not suitable, and it has 36 holes. Please do let me know if there is one available to purchase.

My wife has recently undergone major surgery for a tumour in her head and she will be unable to ride a bicycle for many months.

I am trying to get the tandem finished so that she can enjoy some gentle short rides on the back of it as she is recovering.

I would really appreciate any help or advice on where to find one of these.

Thank you!

It looks like this….

Photo’s courtesy Alexander March

The Spirax Derailleur

Raymond Bon was one of René Herse’s team riders. In the late 1940’s he designed the Spirax derailleur, seemingly quite a revolutionary gear. The main principle of the design was to maintain even chain tension throughout the gears.

One of the disadvantages of the Cyclo gear, as used by most touring cyclists of the period, was that chain tension was uneven, being maintained only by the long spring attached between the derailleur and a lug on the chainstay. The Cyclo also had a ‘dual’ cable arrangement which is a little tricky to set up. Bon did away with both these disadvantages in his design. The gear still moved along a rod with a helical groove, like the Cyclo, but the visible flat coiled spring returned the gear along the rod using its tension. This meant that only a single cable was needed for actuation. There was a second coiled flat spring concealed inside the metal casing, which maintained the chain tension.

It could handle a wide range of gear and chain-wheel sizes, 12 teeth at the rear and 20 teeth at the front. The lever was ‘indexed’ by virtue of a captive ball bearing clicking into the holes in the drilled washer as illustrated in the drawing by Daniel Rebour below. It was also said that the gear could handle a six speed rear block, making it possibly the first six speed gear.

It appears that the gear was available from about 1950 to 1956. Despite the theoretically sophisticated and revolutionary design, it is rarely seen fitted to bicycles of the period. You can see one on a Herse dating from 1950 on pages 156/7 of Jan Heine’s book on René Herse, and also to my Goëland below. So why was it not a great success? I can only assume that in practice it perhaps didn’t live up to expectations. At present I am having difficulty getting enough chain tension on my one!

Do any readers have recollections of this gear and can they perhaps can shed some light on its shortcomings?

Photo’s of NOS Spirax gear reproduced with the kind permission of Chris Protopapas.

Mafac Criterium Brakes – One finger operation?

A recent purchase (thanks Lorenzo!) was this set of Mafac Criterium cantilever brakes. The complete set even includes the braze-on frame bosses. Probably 1960’s but difficult to date because Mafac made these brakes for a very long period of time. Steve Griffith’s useful article on Mafac can be found here . I love the packaging and was amused at Mafac’s claim that ‘un doigt suffit!’ – one finger is sufficent! On the side of the box is an illustration of a cyclist charging down a mountain side with the same caption. Anyone who is familiar with these brakes knows that they do indeed work well when properly adjusted, but I do not recommend one finger operation if you want to stop in a hurry! The packaging shows them coupled to Mafac cyclotouriste or guidonnet brake levers. Its useful to note that Koolstop now make four stud brake rubbers for these brakes, with the same appearance as the originals. They are available in salmon or black colours, the salmon ones being of a slightly softer compound recommended for wet conditions. A nice feature is that when fitted they have no visible branding on them, so they are suitable for period restorations. Although not inexpensive, both types offer a substantial improvement over hard old stock Mafac rubbers.

French alloy mudguards – Mavic INAL and Robineau RBN

Lefol is a familiar name in the manufacture of mudguards or fenders, particularly for their Martelé (hammered type) and Le Paon (Zeppelin type) versions. But here are two lesser known makes of mudguard fitted to quality French touring bicycles… RBN and Mavic. RBN is the brand name of Robineau, based in Paris at least from the 1930’s until the 1950’s. They made mudguards under the model names of Durex, Alrex and Mangalium, and also chain guards. Pictured here are three different versions of the Durex type – the earlier ones fitted to a 1938 Barra have a rather nice scalloped decoration and a very simple script ‘RBN’, whilst the later version fitted to a Pitard, date from the late 40’s or early 50’s and have the more familiar RBN decorative trademark stamping in the shape of a tree. Both types are for 650b wheel sizes, and have flattish profiled sides, whilst the last one pictured is half round for 700c, and were fitted as original equipment to a 1953 René Herse. Obviously Durex mudguards offer superior protection! Mavic, of course the maker of very fine wheel rims, also made mudguards with the INAL model name. Here they are pictured as original fittings on a 1948 Alex Singer. Again, they are for 650b and have flattish sides.

Le Cycliste, April 1936

Old copies of cycling magazines are wonderful sources of information. In this issue of Le Cycliste (the premier cycle touring magazine of France) from April 1936, the adverts show us that the Cyclo Rosa chainset was available at that time in triple configuration in steel, either nickel or chrome plated. Fusion welded steel frames were available from the great Nicola Barra, whilst Reyhand were trumpeting their victory in the 1935 Criterium des Alpes. Another page includes the innovative bicycle design of Jacques Schulz, Le Chat front derailleurs, and Lefol mudguards. Lastly, for amusement, is the advertisement for Hutchinson’s new tyres for Tandems.

Click on images and click again for large scale details