We quite expect to receive complaints for daring to publish an article on bicycles between the chaste covers of Motor Sport. However, this is a period of good will amongst men and it is also a petrol-less age, so that many motoring sportsmen look with less disfavour than was once the case on the humble pedal cycle. Consequently, although we do not ride a bicycle ourselves, we have decided to publish this article by Graham C. Dix, himself a keen motorist with refreshing ideas of what constitutes a good car. His reminiscences of the veteran Dursley Pedersen bicycle may start those car enthusiasts who must now cycle searching for such machines; only recently we met someone at a well-known aeroplane company who used a Dursley up to some eighteen months ago, while we believe that a ladies’ model is still to be seen in use in the Twickenham district. Certainly many parallels with motoring are to be found in Mr. Dix’s story of the construction and development of this unusual bicycle. But we promise nothing more of this sort until the next Christmas issue. – Ed.
Let me start by saying that this article is not about cars in any shape or form, but deals exclusively with that common pest, the pedal bicycle. My only excuse is that many basicless ones, like myself, after examining the possibilities of the solo horse, the horse and trailer, and the human foot, eventually decided that the pedal cycle is the least of all the evils. A preliminary investigation of the market showed that certain other people had also discovered the near-suitability of the machine, with the result that the few new machines left were commanding absurdly high prices out of all proportion to the inferior workmanship employed. On one machine which I inspected the bottom bracket was so designed that the ordinary rotary motion of the pedal tended to unscrew the race housing, with dire results to efficiency. I therefore decided to build up a “Special” out of the odd bits and pieces which are always awaiting the diligent searcher. The purpose of this article is not to give a lengthy dissertation on the art of making “owt out of nowt,” but the above does provide an explanation of how I came to interest myself in the subject of bicycle design. Anyone who has ever constructed or reconstructed a bicycle will have realised how very poor are the designs which are generally employed. It is worth recording in passing, however, that I now possess an excellent three-speed machine for the total sum of five guineas, while to have bought the like new would to-day involve some eleven or twelve pounds.
“The man who could have made a car” was a Dane, the son of a farmer. He forsook the land for engineering and eventually started a factory at Dursley in the Cotswolds, late in the last century. His name was Pedersen. Some of the older readers of Motor Sport may well recall the machine he made, named the “Dursley Pedersen.” I must ask them to forgive any details with which they are already familiar. Pressure of other duties has not allowed me to delve as fully in the subject as I should have liked, and if others are able to correct or supplement my notes I shall be grateful. Pedersen realised very clearly what the essential principles of cycle design should be; he also realised that the accepted trend of marketed designs was the exact opposite, so he started ab novo. His requirements were few, but not easy of achievement. He argued that a bicycle, like a suit, would not fit properly unless it was made to measure. While this would to some extent improve the comfort, there was still vast room for improvement in saddle comfort and springing generally. Lastly, as the whole had to be propelled by human effort, it should be made really light. I will now try to describe briefly how he brought about these requirements.
The whole machine was built upon the cantilever principle and was, in a manner of speaking, doubly triangulated. That is to say, it appeared as a series of triangles whether viewed from the side or from either end. Radiating from the bottom bracket, tubes formed the rear forks and the saddle pillar, and extended forwards and upwards to the top of the steering column and, lastly, to meet the bottom thereof. These tubes, as was the case throughout the machine, were in duplicate, starting from each side of the bottom bracket, and (except in the case of the rear forks) they tapered until they met, forming the apex for a triangle when the machine was viewed head-on. With the exception of the bottom bracket, which was a bronze casting, the frame and forks were built of steel tubes, all of 1/2″ diameter, except for the rear forks, which were 5/8″.
The back ends of the rear forks were joined by two tubes to the top of the steering column, the angles being so calculated that this pair of tubes just cleared the outside of those forming the saddle pillar. The steering column, which connected the ends of the tubes projecting forwards, was a part of the front forks, which formed a unit in themselves. In front two long straight tubes went from the axle to meet at the top of the steering column, each forming the base of a shallow scalene triangle, rather like certain motorcycle forks, with the apexes trailing. A skeleton spacing plate joined the apexes to the bases and also formed the bottom bearing for the steering column. Thus, each side of the fork formed a triangle, and the two sides, tapering together at the top and assuming the axle as a base, formed another when viewed end-on. The handlebars were of similar tubing, passing between the converging tubes of the front forks rather high up, so that no space was left. If you have been able to follow this straggling description so far you will have realised that the whole frame is now connected up into triangles, with the exception of the saddle pillar. Pedersen’s saddle was so constructed that it formed a basic part of the machine. The seat itself was made of woven string or cord, like a hammock, and was bound at the back to a light steel spreader, the latter being hooked up to the saddle pillar by a series of small, horizontal coil springs. The front of the hammock was bunched together to form a loop, through which was passed a leather thong connected to the top of the steering column. With the rider in position, the connection between the top of the steering coluum and the rear axle was in tension, so this was simply connected by a sort of elangated motor-cycle spoke to complete triangulation. This spoke was fitted with a screw nipple so that the tension could be varied according to the weight of the rider; this was the only provision for adjustment on the early machines.
The bottom bearing, housed in the bronze casting, was of standard practice; it was adjusted by a saw cut through the casting, being tightened by a nut and bolt through a pair a lugs. Sprockets varied in size according to the wishes of the various owners, but a considerable number were made with a relatively large number of teeth, amounting to 56, Whereas the ordinary cycle of to-day has about 48. These wheels were cut away to the last thou. behind the teeth, yet even on cycles that have been in use for many years I have not heard of one breaking. Throughout the machine solder was employed for fastening purposes, instead of the more normal brazing. Pedersen realised that surface-for-surface soldering was much less strong, so he broadened out the surface at every join to ensure that the strength was made up by increased area. Besides being quicker and more simple to operate, this method, because of the relatively low temperatures employed, did not affect the delicate tubes.
I have taken a few weights for various portions of Pedersen’s machine and compared them with similar parts taken from a modern bicycle. The results help to prove that low weight is achieved by attention to detail, because in the major parts of the cycle there is only a small saving:–
Pedersen Average Modern
Frame alone … 4 lb. 6 lb.
Front fork alone … 2 lb. 2 1/4 lb.
Gearwheel with cotter, crank and pedal … 2 1/4 lb. 2 1/2 lb.
But in the vital accessories there is a substantial decrease in weight. Owing to the difficulty of weighing such things as brake cables, etc., I cannot prove what I say with figures except for the saddle, which, you must remember, in the Pedersen acted as the crossbar as Mr. Pedersen’s saddle weighed 9/16 lb, as against 2 3/4 lb. for a modern one. Brakes were of his own design and a combination of rod and cable, the former to give a straight pull on the blocks and the latter to allow for the bends and movement in the handlebars. As an example of simplicity combined with low weight, the brake lever was in the form of a wishbone, the fork thereof going each side of the handlebar tube and swivelling on a pin driven though it. On the first machines a further saving was effected by using a plain bearing for the steering head, through a screw with a taper thread. On later models Pedersen bowed a little to convention by introducing a normal ballrace, but even then it is interesting to see just how thin he would allow the track for the balls to be.
At one point in each pair of tubes a small cross-section of tubing was introduced as a brace, and the ends of the tubes, where they tapered to meet, were flattened out to envelope a piece of flat steel cut to the necessary shape; the whole was then filled with solder. The entire weight of the ordinary production “Dursley Pedersen,” complete with carrier (over the front wheel) and bell, was 21 lb. To-day one has to buy a lightweight sports model to get inside twice that figure, yet the reader must not forget that I am comparing a machine that went out of production in 1916 and was designed and first made at a time when automobile engineering was in its infancy and when the use of light alloys was completely unknown. These machines were not made in large quantities, yet they sold for £15-£20 at a time when the ordinary “Dreadnoughts” were costing £10-£15 and were turned out in enormous quantities. Does it not go to prove that the oft-vaunted axiom “Lightness Costs Money” need not be true provided that one builds lightness into the vehicle, instead of simply trying to pare down weight by the use of costly alloys alone? It is worthy of note that a contemporary magazine recorded that an American manufacturer set out to make the lightest machine he could, regardless of expense or durability; it weighed 18 lb.
Some people, had they achieved Pedersen’s wonderful design, would have been content to rest on their laurels as so many car manufacturers have done, but Pedersen was constantly improving his machine. There were complaints that the second-hand market was restricted because the machine could not be adjusted for riders of varying heights, so he first made an adjustable saddle. Weight was then further reduced by the use of hollow, tubular pedal cranks. He discontinued the upturned handlebars because between them rose the point made by the convergence of the front fork tubes, which possibly caused the rider some anxiety should he be thrown forward. In their place came the down-turned bars suspended from this apex, and at the same time the ball-bearing steering. I am not sure whether Pedersen was the first to market a three-speed, but anyway it was available on his machine from 1902. Needless to say, his design was again unorthodox and had certain advantages over the usual epicyclic type. His gear was built in the hub, but operated like a car box, even to a layshaft. This caused a hump on one side of the hub casing, but at the low r.p.m. of the road wheel did not cause instability. The freewheel mechanism was housed within this casing and so was entirely free from dirt. The gears were straight toothed and strongly made, every one running in ball-bearings. The whole of the casing over the layshaft was hinged so that it was very easy in case of breakdown to expose the whole unit. The gear weighed the same as the modern epicyclic, viz. 3 lb., but I consider it to be vastly superior in accessibility and to cause much less friction in use. Apart from building his production machines, Pedersen may have had an eye on the basicless future(!) when he also designed tandems and built one machine for four riders. Be that as it may, he was certainly 40 years ahead of his time when he offered to produce a folding bicycle for the British Army, to be used by the ordinary soldier as and when possible, and to be carried at other times. The complete weight was to be 11 lb. Needless to say, the Army turned it down because they did not consider it had any practical value. Thirty years later his idea has been taken up for use by paratroops, but even now I doubt whether his inclusive weight has been reduced in spite of the advances in metallurgy.
It should not be thought that Pedersen devoted the whole of his time and energy to the manufacture of the bicycle. He was equally successful in the field of agricultural machinery. He also constructed a motor-cycle weighing only 60 lb. and made a multi-speed gearbox for a car; he could not raise much enthusiasm for these two latter, however, and never made them marketable propositions. He designed and made a quick-firing gun, which he submitted to the War Office, and he had an answer to all their questions and was able to disprove all their objections, so they finally turned it down with the excuse that, although it was, in itself, suitable, they would not be able to supply ammunition quickly enough for it! So, in the early days of the century, the cycling cognoscenti were able to enjoy the same advantages over their brethren as the owner of the sports car has to-day over the family saloon, but while the owner of the “Dursley Pedersen” could be confident that his machine was 30 or more years in advance of other cycles, thanks to the conservatism of the British car manufacturers we now have to do our best with chassis that were out of date by the world’s standards 10 years ago. The comfort of the hammock saddle was only to be believed when experienced, luxurious riding being provided by the coil springs, aided by just the right amount of whip in the frame itself. The light weight, coupled with the high gear, provided endless effortless cruising, so one could ride a Pedersen much further than the average machine, with greater speed and without becoming so tired. As evidence of this, Pedersen (no longer a young man), with his Shavian beard, was often to be seen cycling into Gloucester and back after he had closed the factory for the night – no mean feat, for the distance was 30 miles and the roads were in even worse condition than they are to-day. The reader will now be wondering why he has not seen many of these excellent machines in use, and whether Mr. Pedersen is hiding the light of his genius behind a thoroughly merited title. But to make a profit on cycle manufacture, as on anything else, it is necessary to have a large market, and this Pedersen could not command. He was an engineer, not a business man. (He was once known to spend six weeks on end personally lightening a cycle by reducing the thickness of the tubes, except near the joins.) And who can explain the whims of the all-powerful British public? Among enthusiasts his machines achieved a certain popularity until the outbreak of the 1914 war, but then, with difficulties of all types piling up, he was forced to sell his designs and patents to another company, in whose hands they soon became extinct. Pedersen was for a time Professor of Engineering at Stockholm University, then he returned to his native Denmark, soon to die in comparative poverty. People bought bicycles then as they buy motor-cars to-day, not because they are the best or most suitable for their needs, but because they are the cheapest, because they look like Mr. Jones’s next door, because they are sufficiently gullible to believe what they are told, however obviously it may be a departure from truth and fact. For the things that really matter they care naught, and so another genius was shunned, another masterpiece was thrown away, as things of no account. Now, in his workshop a few miles from the original factory, a friend who is an engineer because he loves engineering, a man after Mr. Pedersen’s own heart, is rebuilding a “Dursley Pedersen” from original parts found on local scrap heaps, as a tribute to one of the few men who could have made a car, and the only man who has ever made a bicycle.
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