Vol.1, Issue 15
Posted: Thursday 18th June 2020
C L N 14 explained that I was just about to build up my recently acquired 1957 Rotrax frame. This is now done and the specification is: 27” Fiamme Milano HP rims on Mil Remo LF G/F hubs with 14-24 5-speed freewheel (taken from my Flying Scot); Williams C1000 42t chainset with Allez pedals and toestraps; Campag Gran Sport rear changer with down-tube lever; GB alloy spearpoint stem with Maes bars and GB Coureur + brakes (introduced in 1957); Brooks B17 narrow saddle. Here are two images of the completed build. I do have larger clearer images if you would like to see them. I haven’t as yet positively identified the model as I cannot find a 1957 brochure. It cannot be one of Rotrax’s top models, Concours or Super Course as their lugs are very elaborate and distinctive.
These lugs are Legere 45: I wonder if it is La Premiere? I have sent details to the marque enthusiast but not heard from him to date. From an old copy of Cycling I did find a cycle test on a Rotrax Prima (1958) but that had Nervex Professional lugs and was introduced one year later than this frame. I am assuming that it is a La Premiere for now. I remembered that I had a set of matching green mudguards which I set up to fit this frame. Now this is done it should be easy to put them on and off.
The worst thing is having to set the guards up to measure the stays and then having to take it all apart to trim them down. I have done it in situ before but I find that it is all a bit nerve wracking trying not to scratch the guards with the hacksaw. I rode the Rotrax in the Boot and Back on March 7th and was very pleased with it as it felt very sure-footed (or tyred) in the wet and slippery conditions.
In the last edition I forecast that I would be spending a lot of time juggling with bottom bracket axles – how right I was! I decided to upgrade my Flying Scot which had a single Brampton chainset to a double Stronglight/TA cottered set up: this has the cranks with the smaller oval logo. I have a very crude way of measuring axles from the inner bearing edge to the outside edge of the crank. I had a note that the Ephgrave with Durax double chainset was 32/36. Checking the existing axle showed it to be 32/34 so I tried 32/36, this nearly worked except that bolts on the inside of the chainring just caught the chainstay. Out with the axle and I eventually found a 34/38 which seemed to do the trick.
What I can’t understand is that when I was building bikes in the 50s there were two axles, ‘normal’ and ‘chaincase clearance’ and I wonder when all of these variations came into play. Whilst searching I also found axles in my box which were narrower in one case and wider in the other across the two bearing surfaces. The day after writing the above chapter I was reading Cycling from 1951 and saw a letter which asked what the writer should do as he wished to fit a double chainset to his machine. The answer from Chater Lea was to fit one of their tandem axles!!
When I transferred a double chainset and BB axle to Patricia’s Flying Scot I realised that this axle was also wider across the bearings. Luckily just the right axle was sitting on the bench nearby, the result of my juggling with the Rotrax. I was moving her BB from a Pat Hanlon which was already built-up when we got it. The BB had a Campag right-hand cup, TDC LH cup with Baylis Wiley lock-ring and Stronglight axle – shame there was no room for a Chater component as we would have had a full hand. This was what I call a typical 50s wife’s bike made up by the husband with any old bits he could find left over from his own irons. No chance of getting away with that with Patricia as she knows every nut and bolt on her machines.
This all reminded me that some years ago I was struggling to find an axle of the right length for my Ephgrave, the problem being that the Chater-Lea chainset was a bit too far out for ideal chain alignment. Someone suggested, ‘put the axle in the other way round’ which I did and never had trouble again ( it was 32/34) but I guess my left pedal is 2mm too far out!. I expect you noticed that when you were riding behind me on the last Reading Ride but were too polite to say anything.
As you can see, the purchase tax content is quite high. This is why in the 40/50s I would estimate that at least 85% of lightweight machines were bought as frame plus components to be built up by the owner. By doing it this way no purchase tax was payable so one could get a much better machine for the same price.
The result of this was that no two cycles were ever quite the same although, even in those days, fashion would dictate the build to some extent. One would find that members of one club would all build their machines to one spec. whilst at another club a few miles down the road they would all have a different idea for the winning formula.
Nina had a Brooks Swallow saddle, Simplex 4-speed gear, Dunlop steel 27” rims with Dunlop HP tyres, GB brakes, Chater chainset skimmed to take 3/32 chain, Allez pedals plus modified Madison bars (see below).
In this era, it was the mode to have the seat only an inch or so above the top tube and obviously the bars would then be set as low as one could get them. In the case of six-foot plus riders though this was not an option as 24” frames were about as big as most builders produced, so we had to go around with a very ungainly looking 4” or so of seat pillar showing.
How different today when riders have extra long seat posts, some even up to 12”.
In C L N 14 I mentioned the practice of local riders (Cambridgeshire Road Club) filling the bars with sand and then bending them. I thought that this was done to lower them. However John Beynon tells me that the reason was to reduce the forward throw of the bars. Having done this one could then fit a very long extension to get the racy look. When John explained how it was done all became clear. To quote, “Imagine a pair of Madisons correctly fitted, then loosen the stem nut and rotate the bar ends backwards and upwards until the forward reach almost disappears. Then retighten the stem nut and bend the bar ends down to the horizontal”. He goes on to explain that this was done off the bike with the bars packed with sand. (See Nina’s bars above). Although Nina was not so tall she was able to have a reasonable stem fitted rather than having to do with no forward extension.
Funnily enough we have tackled the same problem with Patricia’s machines. Not being so adventurous we fitted GB Capo Berta bars, which had little forward, throw and achieved the same result. Some months ago, in N & V, Peter Paine in his role as GB Marque Enthusiast reprinted a GB bar catalogue showing the Capo Berta amongst others.
The Cambridgeshire Road Club’s most famous member (after Nina) was Freddie Krebs who went on to compete in the Tour de France as a member of the Hercules team and he was instrumental in many of the fashions undertaken locally such as the aforementioned bar bending. Another was to mix-and-match Chater rings with Granby alloy cranks and Alp brakes with San Giorgio levers, also droopy stems made to order by Rotrax with more drop (the result of oversized frames) than forward reach.
Machines favoured in the club were Carpenter, Rensch, Claud Butler, Hobbs, Higgins, Gillott and Granby plus a few others. Fred Kerbs had a mustard yellow SEG Ferris with chocolate coloured lugs – seems like he was a better rider than arbiter of taste. The club is now defunct and the biggest club in Cambridge is Cambridge (Town & County) CC also known as Cambridge CC which has over 100 members.
At the Boot and Back I was given a copy of Practical Mechanics from 1949. The donor had read that I had an R O Harrison Shortwin and there was a description of this model in a Cycle Show review. I was also interested by the following: “Dealers will welcome an innovation by Baylis Wiley. On their Continental hubs the rear flange is wider in diameter than the front, thus permitting a spoke length of 11 7/8” for front and rear in conjunction with 27” rims.” I had never realised that this was the reason for the differing diameter of front and rear hubs, I had assumed that it was to give a better spoke load line for the drive hub. This was in the days of 32/40 hubs when it was traditional to do 3x for front and 4x for rear which would of course necessitate spokes of differing lengths if the hubs were identical.
The article went on to give the show attendance figures of 70,000 for the Saturday. This was the first show after the war period, following a ten-year break, but still I find that amazing. I had wondered why there was so much about cycling in this magazine when I noticed the small print on the title page: “Owing to paper shortage, The Cyclist, Practical Motorist and Home Movies are temporarily incorporated”. C L N will have to be re-titled – ‘Memoirs of a Post-War Upbringing’ if this goes on.
The week after the Boot and Back we joined the North Road Section again for their Tin Can Ride. Six riders turned up at the start and three more joined us at the lunch stop. Patricia and I took a Hobbs with SA AM and a Macleans with SA FM which were the two fitted with much-needed guards. The ride out was dry and windy and the return was wet with gale-force winds. Patricia has always been very pleased with the steady handling of the Hobbs (Superbe) and was pleased to have it out on this blustery ride. The next day Bryan Clarke and I had a short lunch-time ride: he works in Cambridge and was testing his very nice Innanzi Tutto with a SA AM gear. The paint job (being a bit girly here!) was very nice in Burgundy with light blue seat panel and head tube with matching guards and bar tape – lugs lined in gold.
It was fitted with Bowden brake calipers which look as if they were made by Agrati, an unusual touch – he had mated them to a pair of Universal levers. The wheels had 26” Weinmann rims. The chainset was Williams 5-pin with the distinctive ‘K’ ring. Bryan has been trying to assess the date of this one and I would think that 26” wheels would suggest the 1946–50 bracket. Bryan had been told that his ‘D’ section forks went out about 1949/50 to be replaced by oval sections.
Quite often with these older frames the rear ends were spaced for fixed wheel usage (110mm), it is very tricky to fit a derailleur (really needs 120mm) so people often fit a Sturmey in order to give a little help to these tired old legs on the mountains which surround us here at Cambridge.
I have now built up Patricia’s 1970 Flying Scot. Being 1970 we had to use different components – all of her other machines are in 1945-48 range. The frame is 19” and unusually it was built for 26” wheels so we have fitted a stock pair of Airlite LF G/F hubs with Dunlop alloy HP rims; not what one would expect on a 70s bike but there was no way one could fit 700s. Sprockets 5-speed 14-22. The gears are Campag, Nuovo Record rear with Gran Sport front, both operated from twin Campag down-tube levers. The chainset has 5-pin Stronglight cranks with an alloy TA double chainset conversion 36/46. GB ‘Chromo’ 8cm stem with narrow Maes bars. Weinmann brakes which are period as they do not have any of the plastic bits so many Weinmanns have.
We have had to compromise on chain length – I have had links in and out like a fiddlers elbow! In the small front ring the chain is too slack on the small sprocket. Take a pair of links out and, in the big ring, one can only use 2 or, at the most, 3 of the smaller sprockets before it is too tight for comfort. The problem is no doubt that the Campag gear will not take up a 10 tooth chainring difference. This is the result of liking the look of ‘racy’ changers rather than the long arm touring type, a form of bikie snobbery I guess.
Patricia had just decided to draw a line under her collection when the phone rang to tell us about a local 19½” Gillott (she already has one) with 26” wheels – watch this space!!