Very little is usually known about the early days of large industries . Few of the pioneers bothered to record their own efforts ; in fact they were more concerned to hide them from the world and their possible rivals until a measure of success had been achieved and financial returns seemed possible . All this is certainly so in the case of motor vehicles ; the records are fragmentary , and it seems likely that many early designs were lost or destroyed . The real ancestors of the motorcycle were perhaps the steam tricycles which were made from the eighteenth century onwards ; many of them undoubtedly ran , but as they were not usually permitted the use of public roads , the incentive to build them must have been largely academic .
The problem of applying the internal combustion engine to road vehicles was tackled independently by several engineers in the mid 1880s . N. A. Otto had laid down the principle of the four-stroke cycle in 1876 and Clerk did the same for the two-stroke pumping-type engine in 1881 . Both methods were tried in the very early engines , but the enormous difficulties making a workable mechanism out of a mere principe can be understood when one reads , for instance , of the experiments which were carried out with gunpowder as the propelling agent . Many of the early workers undoubtedly followed impracticable ideas , but few of those whose names we know failed to add some contribution to progress .
We must remember , too , that in the 1880s even the bicycle as we know it did not exist - a two-wheeler was almost necessarily a penny-farthing , and what was known as the " safety " bicycle , invented by Starley , did not become popular until the early nineties . For this and other reasons such as the weight of the engine , the first motorcycles all had more than two wheels .
It seems possible that the first motorcycle successfully built and run was produced by an Englishman , Edward Butler , of Erith . His design dates from 1884 , and the machine was certainly in running order in 1886 or 1887 . It was a tricycle with a steering pair of front wheels , one each side of the drivers seat , and a single wheel behind flanked by two cylinders which faced forward with piston rods working on crossheads and long , curved connecting rods transmitting the power from there to the live axle of the rear wheel through a chain drive and a six-to-one reduction gear . The cylinders were water-cooled and , unlike any other design for years afterwards , Butler employed a float-feed carburettor and electric ignition . Things like these seem to us now an essential part of all petrol engines , and it is strange how long some of the pioneers struggled with unpractical alternatives .
Butler's machine was not developed any further , since there was remarkably little encouragement for motor vehicles in this country - in fact they were restricted by law to 4 m.p.h. , although it is not true that a red flag was ever carried in front of a motor vehicle . Continental soil was more fertile at this time , however , and Gottlieb Daimler , usually thought of as the father of the motor industry , produced his first machine in 1885 . This was a primitive hobby-horse type of bicycle with wooden wheels , with the engine mounted vertically in the frame and two small outrigger wheels to ensure that the arrangement remained approximately vertical . It was intended more as a mobile test-bed than as a road-going concern , but the engine showed considerable promise and a two-cylinder version was built before the inventor turned his attention to cars . The engines possessed an aluminium crankcase containing a connecting rod working between two flywheels in the modern fashion , air cooling and a primitive form of poppet valve.
One or two other inventors produced motor tricycles with a single front wheel , notably Carl Benz of Mannheim , but these were generally coachbuilt and partook more of the nature of cars than motorcycles . J. D. Rootes , however , built a motor tricycle with saddle and handlebars in 1892 , and his general layout was followed by most of the subsequent designers . His water-cooled engine was inverted behind the rear axle - a two-stroke unit using vaporised oil and driving via reduction bevels . It seems to have been a practical layout , although details of its performance are not on record .
The year 1895 brought some important advances ; in France the Marquis de Dion modified Daimler's engine and installed it behind the rear axle of a pedalling tricycle . The engine was now quite a practical proposition and the machine proved a commercial success , being marketed up to about 1902 , not only by de Dion but by many licensees and imitators ( plate 1 ), and was developing all the time.
A German motor bicycle appeared in 1895 under the name of Hildebrand and Wolfmuller , and a number were sold to the public , one being imported into this country for demonstration purposes , finally ending up in the Science Museum . They had open duplex frames ; the two water-cooled cylinders were horizontal , open-ended , and driving the rear wheel by directly coupled cranks . The firm's trade mark was a little angel . A somewhat similar layout was designed by Colonel H. Capel Holden in the same year , but his cylinders faced each other in two pairs , with a crosshead and long cranks to the rear axle , the rear wheel being made very small for " gearing down " purposes . This has claims to being the first four-cylinder motorcycle , and arrangements were made to produce it commercially . It came on the market in 1899 , beautifully made and finished but already out-dated by new developments , and not many were sold .
In 1895 , too , an American , E. J. Pennington , built at Coventry a bicycle and a tandem , both fitted with two-cylinder engines projecting behind the rear wheel and driving it by direct-coupled cranks . The cylinders had no cooling arrangements ; carburation was merely a petrol drip into the intake tube , ignition by battery and coil with a wiper contact on the piston heads . The layout was not practical , although the machines were persuaded to go for short distances for demonstration purposes and were supposed to have attained 30 m.p.h. The silver-tongued American returned to the States £100,000 richer , but no further examples were ever built .
The pedal cycle was now well established ; it had tangent-spoked wheels , pneumatic tyres and driving chains , all items useful to ease the path of the motorcycle designer . Open cranks and exposed pistons in those days of dusty roads and deep muddy ruts must have reduced the life of the engines to a few hundred miles , even if they could be persuaded to go as far as that ; no more were built after the Holden , all subsequent machines having enclosed crankcases . Surface carburation was , however , universal up to the turn of the century - a method by which air was drawn through the petrol tank by the engine , vaporisation being assisted by the exhaust pipe passing through the tank . The air/vapour mixture needed continual adjustment according to weather and road surface , and speed changes were usually effected by advancing and retarding the ignition , where this was electric . Often , however , it consisted of a dangerous contraption involving a platinum tube kept hot by a small petrol burner which fired the gas in the cylinder by pre-ignition , and usually set fire to the machine whenever there was a skid .
The Beeston motor tricycle appeared in 1897 , very much along de Dion lines , and attained popularity . The firm also made quadricycles , an arrangement based on a cycle frame with four wheels , an engine behind and a basket seat or padded chair for a passenger between the front wheels . Some of these machines were even exported . Another tricycle , the Bollée , well designed with a low-slung chassis , front passenger seat and single-cylinder engine alongside the rear wheel , earned quite a name for speed and reliability , aided as it was by a three-speed sliding gear much in advance of its day . This was to have been made under licence by Humber , but a fire destroyed their factory about this time , so a separate firm , the British Motor Syndicate , was organised to produce a number of variants . Humber themselves had been building a " tricar ", a cycle with two front wheels , a passenger seat between them , and an engine mounted behind the rear wheel . This they called the " Olympia Tandem " and exhibited it at the 1899 show , although sales were few .
The motor tricycle industry was well under way and a number of famous firms were producing variations of the de Dion layout , notably the MMC ( used in the Boer War ), the Enfield , with de Dion engine , the Dennis , Swift , Riley , Star , and the Ariel , which moved the engine forward of the rear axle , thus greatly improving the weight distribution . Two-wheelers were at a discount , and the only one made in any quantity , the Werner , had a particularly bad reputation for sideslip . This is hardly surprising when it is realised that the engine was mounted above the front wheel and was fitted with hot-tube ignition . The model was first put on the market in 1897 in France , and it was made under licence in Coventry , with coil and battery ignition , in 1899 . Several good examples remain ( plate 2 ). One more advanced design appeared before the end of the century ; this was a motor-wheel designed by Perks and Birch and later taken over and produced by Singer ( plate 3 ). The engine was enclosed in two spoked aluminium plates forming the driving wheel ; it was fitted with a surface carburettor and with a low-tension magneto - probably the first design to be so equipped . The unit was compact and well thought out , and could be fitted to any bicycle or tricycle , but its cog-wheel drive made it harsh in power delivery , and it had very little power anyway .
Early Develoment 1900-1914
The last chapter dealt with the origins of the motorcycle in some detail , and although few who read this will ever have a chance of owning a nineteenth-century example , it is right that the struggles of the first pioneers should be recorded . These men , in the days when even metallurgy was in its infancy , attempted to translate half-understood theory into practice without the benefit of written manuals , training , experience or any of the aids to design which might today be thought absolutely essential . They had only their own craftsman's instinct to guide them , and the progress they made was remarkable , especially in the face of the violent and unreasonable prejudice to which they were exposed . As a result of their efforts , the new century ushered in a period of prosperity , when the motorcycle with two , three or four wheels became available in quantity and variety , and offered the purchaser some degree of reliability . Stops by the wayside continued , of course , with some frequency , but in the majority of occasions they concerned something which the ingenious could remedy on the spot . Each increase in engine efficiency showed up weaknesses in forks , frames , spokes and transmission , and every motorcyclist was an expert puncturemender : horse and hob nails abounded and tyres were very thin . Ignition parts were mostly made out of what has been described as a form of metallic putty , the life of plugs and valves was short , and most people carried plenty of engine spares - and often a whip for hostile dogs . Motoring life was certainly still an adventure into the unknown , but it was possible for an ordinary tourist to cover big mileages with success .
The years 1899-1901 saw the beginnings of quite a number of firms whose names were to become famous in the industry for all time . The earlier year saw the beginning of experiments with Werner-type engines designed to clip to ordinary cycles . Machines along these lines were produced by the brothers Harry and Charles Collier ( both later destined to win the TT ), and by Alfred A. Scott ; these activities led within a few years to the founding of the Matchless and Scott factories respectively . Joah Phelon in 1900 took out patents for a very neat engine arrangement with inclined cylinder taking the place of the front portion of the frame and a chain drive to the rear wheel ; this design led to the foundation of the Phelon and Moore factory at Cleckheaton , and machines of basically similar layout were built under the Panther trade name as late as 1963 . The design was adopted and produced by Humber under licence for both bicycles and tricycles ( plate 4 ).
The Raleigh and Enfield concerns both manufactured variants of the Werner design in 1900 , the latter having a long twisted rawhide belt driving the rear wheel . Belt drive was certainly the answer to the harsh transmission of the earlier machines , but brought with it troubles such as unreliability , and slippage in wet weather .
The two-wheeler was gaining ground , however , and a great step forward was taken when the Minerva engine became available . This was designed in 1899 by two Swiss engineers , and produced in Belgium ; of 211 cc capacity , it was provided with attachments to clip to the front down tube of any bicycle and thus made it possible for almost any cycle shop to become a motorcycle factory . Scores of them did ; the first substantial firm in this country to adopt it on a large scale seems to have been Bayliss-Thomas , late in 1900 , under the Excelsior trademark , and they were followed by Alldays , Enfield , Ivel , Phoenix , Coventry-Progress , Quadrant and Triumph , all in 1901 . This year too saw the founding of the Indian concern in the USA , and of AJS , when the Stevens brothers marketed a machine powered by a small American engine called the Mitchell . Other firms of note to launch into motorcycle production about the same time included Imperial Cycles ( later New Imperial ) with an all-British machine powered by a 500 cc engine and direct belt drive , and OEC , a racing 4 hp design by F. J. Osborne , built in Coventry .
The Minerva engine underwent continuous improvement , and by 1903 both valves were mechanically operated by cams situated in the crankcase . The old automatic inlet valve , opened by the suction of the engine and closed again by a weak and very sensitive spring , had the big disadvantage of power loss at low revolutions ( plate 5 ); nevertheless , there was a surprising amount of opposition to positive operation of the valve on the grounds of " complication ", and the old type lingered on until the First World War .
1902 brought designs by W. Hillman of Coventry and William Morris of Oxford , also the Rex , which won a great reputation as a speedster , the Hobart and the Coventry-Eagle . Alfred Scott started production of a two-stroke engine-assisted bicycle strikingly unlike his later machines . On the whole , manufacturers were very reluctant to design special frames , the " clip-on " type of motor was very much the order of the day , and even this was not expected to do more than assist the exertions of the cyclist . Now , however , Werner came out with a completely new design , having a frame built to hold the engine vertically low down in what afterwards became the conventional position . The machine had power and reliability and won most of the competitions for which it entered ; its effect on future design was profound and its merits were speedily evident to many British engineers . Although the Werner layout was well protected by patents , these were circumvented by various forms of loop or cradle frame , and before the end of the year vertical engines mounted inside the frame were available from many factories including Clarendon , James , Quadrant , Bradbury , Rex , New Hudson and Phoenix , while on the Continent , Peugeot , FN and NSU followed the same trend . James Norton , chainmaker , used the Clement engine in a machine he offered under the name " Energette ". Various British factories produced proprietary engines , the most important of which was the JAP , fitted by Triumph in 1903 , and this year also brought the first commercial sprung rear frame , marketed by BAT , the Rover motorcycle , and the first sidecars in a variety of tentative designs mostly based on leather-backed or wickerwork armchairs with footwells ( plate 13 ). They speedily ousted the two-wheel armchair trailer which had been hitched on behind the saddle and had proved the most uncomfortable and dangerous form of passenger transport known .
Number plates became compulsory in 1904 ; the speed limit was raised to 20 m.p.h. , and good spray carburettors and high-voltage magnetos came on the market in quantity . Bowden wire controls were introduced and front forks were strutted for strength ; one or two makers such as Quadrant even fitted a crude form of sprung fork . The rubber and canvas V-section belt began to replace the twisted rawhide drive ( as fitted to treadle sewing machines ) and JAP put on the market an engine of overhead valve design . 60 m.p.h. was attained on racing tracks . Altogether , the motorcycle was gaining strength and constructively measuring up to its problems , but it was just at this time that a big recession set in . The flow of new designs slowed down as sales dropped , even though 1905 saw the flat twin design by Joseph Barter ( later to engine become the Douglas ), a side-by-side vertical twin by Berclay , and the first four-cylinder FN . Many firms vanished overnight and it became evident that a large proportion of designs were underdeveloped and unfit for marketing . It seemed that only Triumphs , under their extremely able director J. M. Schulte , were able to maintain their sales . Phelon and Moore , however , were leading the way in design by introducing a trouble-free two-speed gear involving two chain drives to a countershaft fitted with a selective clutch ( a layout later to be adopted by A. A. Scott ), and by boldly omitting the pedalling gear . V-twin engines were now on the market ( plate 9 ).
Interest returned in 1907 with the establishment of the TT races in the Isle of Man , and the building of the Brooklands track . Designers had previously attempted to win races by fitting larger and larger engines into lighter and lighter frames , but the new facilities for racing showed the fallacy of such ideas and proved ideal testing grounds . They aroused considerable public interest and ruthlessly pinpointed all weaknesses of design . The benefit to the industry was incalculable , and the motorcycle rapidly gained in speed and reliability .
In 1908 Scott marketed his water-cooled two-stroke twin , built by Jowetts and equipped with two-speed gear and kick-start ; it caused a sensation and speedily gained its long-lived reputation in competition work . Another outstanding design to appear was Barnes's Zenith Gradua , which provided a change of gear by opening and closing the pulley flanges on the direct-belt drive and simultaneously sliding the rear wheel in and out to maintain belt tension . The system was successful enough to be barred from hill-climbing competitions as " unfair ", a fact of which the manufacturer took full advantage in his advertisements .
Chater-Lea entered the market in 1909 with a V-twin of excellent quality , and from 1910 the trade recovered steadily ,
and design improvements came in a steady flow . The need for a " free-engine clutch " was beginning to be understood in the thickening traffic , and a number of two-speed gears appeared , notably on a well-designed Royal Enfield light twin with Vickers engine . Veloce reappeared with a workaday sidevalve model and Lea Francis designed a luxurious machine with a countershaft gearbox mounted behind the engine in what later became the orthodox position , fully enclosed chain drive and a V-twin engine from JAP ( plate 12 ), thus forestalling by two years the almost incomparable Sunbeam , with its enamel almost as hard as steel , designed along similar lines . Other new firms that year included Clyno , Omega , and the four-cylinder Wilkinson with a bucket seat ( plate 8 ). A number of rotary-valve engines were tried out on the public with limited success ; the best of them was the Corah . Rudge-Whitworth and BSA joined the ranks of the larger manufacturers , DOT produced a dropped frame with low saddle position , and PV a good rear-sprung frame . Two-stroke light-weights began to appear , the Levis of 1911 being the first popular example ( plate 7 ); three-speed hub gears , stronger versions of those on contemporary bicycles , also became available from Armstrong and Sturmey-Archer . They were remarkably compact and ingenious pieces of mechanism , excellent when expertly maintained but tricky to adjust and liable to destroy themselves if not looked after . In the same year Rudge produced their famous " Multi " gear , with fifteen notches on the gearchange , operating on movable pulley flanges on both engine shaft and rear wheel , allowing the engine to slow down as the machine gathered speed very smoothly , and it became deservedly popular ( plate 14 ).
Both Villiers and Blackburne offered proprietary engines in 1913 , many of the larger manufacturers revised and extended their ranges , and new names included the Ivy , Hazlewood and Royal Ruby . The fashion for 1914 seemed to be for larger engines , the Rudge Multi going to 750 cc and the Excelsior even to 800 cc in one cylinder . New V- and flat twins became available , notably designs by W. E. Brough , W. A. Weaver ( Montgomery ) and Granville Bradshaw ( the first ABC ). Two-stroke lightweights proliferated , notably from Clyno , Connaught , Levis , Radco , Velocette , and also Triumph ( plate 18 ) , who fitted a two-speed countershaft gearbox . Starting these machines was very easy , and some of them dared to dispense with pedals . The new Calthorpe lightweight and the JES motorised bicycle both had small four-stroke engines .
This brings us very briefly to the end of the veteran era and the outbreak of war . Civilian machines continued to be available for the time being but in reduced numbers .
The Vintage era 1915-1930
It bas been said that there is nothing like a war for advancing research and design , and the motorcycle of 1920 certainly showed very considerable improvements over the corresponding 1915 designs even though production for civilian use ceased in November 1916 . Output for war purposes was of course , stepped up and the factories were never so busy ; the bulk of the Army requirements was met by Triumphs , who turned out over thirty thousand units during the course of hostilities , nearly all of them fitted with the new Sturmey-Archer three-speed countershaft gearbox and belt drive . The reliability of the machines brought the universal nickname of " Trusty ". Douglas , too , made considerable numbers of their lightweight two-speed flat twins , all finished in khaki paint ( plate 22 ). In the early days , when a war of movement was expected , orders were placed with Clyno , Royal Enfield and Scott for twin-cylinder sidecar machine-gun outfits , but few of these were made . RAF contracts were allotted to Phelon and Moore , Sunbeam manufactured for foreign governments ( plate 17 ) and even turned out some belt-drive machines to order , but doubtless against their better instincts . A few Rudges and BSAs were also exported for use in distant parts . Later in the war Alfred Scott produced a three-wheeler capable of taking machine-guns over rough ground ; it was an extremely practical vehicle although its appearance was distinctly odd - something like a sidecar outfit enclosed in a dishcover with a radiator in front . He was not awarded any contract , but the factory developed the idea later for civilian use as the " Scott Sociable ", known more familiarly as the " Crab ".
Some months after the armistice the industry was permitted to revert to civilian production , and the results of wartime thoughts about design became evident . Demand was enormous and prices soared accordingly until such time as the supply situation caught up . One or two pre-war designs were reintroduced with more or less modification , such as the Rudge , the lightweight Triumph and the Norton with its now old-fashioned direct-belt drive and their fast engines with a guarantee of 70 or 75 m.p.h. Apart from the few diehards , direct drive was no more , nor were there any such things in the shops as chain-and-pedal starting or hub gears . The industry had at last realised that there was an essential need for a three-speed countershaft gearbox mounted behind the engine , and nearly all machines were fitted with a multiplate clutch and kickstarter . By 1923 all the larger machines were turning over to all-chain drive , and sidecar outfits at least had dynamo electric lighting . Frames were lower and the top tube was inclined or curved to provide a lower saddle position and enable the average rider to put both feet on the ground . Brakes improved and the era of the internal expanding brake design was but a year or two away ; tyres also improved greatly and the safer wired pattern began to supplant the old beaded-edge type which was inclined to jam the wheel dangerously when punctured .
The pent-up enthusiasm of the war years and the soaring demand had tempted many people to enter the industry in a small way and innumerable brand names came on the market , mostly to wither and vanish within a year or two . There was a boom in cheap scooters and in very lightly built cyclecars , some of them with wooden frames , but by about 1922 they were all gone , the sound and experienced Morgan design alone being left to , continue for another twenty years . The motorcycle itself was now a thoroughly practical affair , able to go anywhere in the world with comfort , speed and economy , and the variety and quality of British machines available for touring or racing were unmatched in any other country then or since . All forms of motorcycle sport throve , long and historic tours were undertaken throughout the five continents and records were broken regularly . Literally dozens of firms created competition departments and strove to carry off honours at national and international races , and rivalry was so keen that almost every race could be won by any one of the entrants . Enthusiasm and sportsmanship mattered in the main more than pot-hunting , and a racing clubman would have laughed to scorn the idea of taking his machine to meetings in a van : motorcycles , even racers , were after all for riding .
Year by year improvements were made in the hopes of stealing a march over one's rivals ; design was fluid and there were plenty of differences of opinion about the best features of an efficient motorcycle . One saw an immense variety of machines on the road or at club meetings , and the comparisons and arguments were endless . Roads were uncluttered by very many cars - the " blue , empty roads of Britain " they were called by Lawrence of Arabia , and almost everyone you met was a fellow enthusiast .
This was the day of the businessman-devotee who founded his own firm , designed , built , rode and raced his own products , and sold them to the public . This had already been done , of course , by A. A. Scott , James Norton , the Collier and Stevens brothers , but the scope was now wider . Jock Porter won the 1923 Lightweight and 1924 Ultralightweight TT and went into production with his machine , the New Gerrard , in Edinburgh . Howard R. Davies , having won the Senior TT in 1921 on a 350 cc AJS , considered he could design something better , and proceeded to win the 1925 Senior on a machine of his own make , the HRD . This was put on the market , proved a success , and was later fitted with the Vincent spring frame . As the Vincent-HRD , it became one of the most famous of all post-Second World War machines .
George Brough was perhaps the doyen of them all . Dissatisfied with existing designs in 1919 , he built his own big twin racing solo , and with it took fifty-one fastest times at fifty-one meetings ( plate 19 ). The fifty-second brought disaster when a tyre came off , so he turned his attention to producing machines to order , first in the factory of his father , W. E. Brough , and later , as the Brough Superior , on his own ( plates 25and 29 ). His flair for publicity led him to design a tank shape so distinctive that his machines were instantly recognisable and the appearance continued very little altered until the last were built in 1940 ; the saddle-tank was probably his invention . The machines were made to personal measurement and were expensive , and Brough earned his reputation as the maker of the " Rolls-Royce of motorcycles "( plate 21 ). It was rarely that the autumn show did not provide a sensation by way of something very unorthodox from the Nottingham factory . " G.B. " himself entered regularly for all British and European long-distance trials and was at one time the fastest man on two wheels .
There were so many other practical racing men that it seems invidious to give further examples , but the merits of two more at least demand a mention : C. G. Pullin , winner of the Senior TT in 1914 , designed and marketed the Pullin-Groom in 1920 and the Ascott-Pullin in 1928 , both luxury allenclosed machines much before their time ; and F. W. Dixon who won the 1923 Sidecar and 1927 Junior races and who completely redesigned the then old-fashioned Douglas range in 1926 . Other designers of undoubted genius in the motorcycle sphere included H. R. Ricardo , remembered for his 1921 four-valve Triumph design , and Granville Bradshaw , an engineer of particularly advanced ideas , responsible among many other things for the Sopwith-built transverse twin ABC , the oil-cooled overhead valve Bradshaw engines ( plate 27 ) and the transversely mounted V-twin Panthette . His designs received universal respect due to their original approach but are said to have required skilled attention to keep them in good running order , and they were rarely competitive in a commercial sense . Barr and Stroud , two Leeds University professors , left their appointments to found a firm for the manufacture of single-sleeve valve engines . Designs of this kind involve a thin steel sleeve with holes cut in it to register with the ports and which moves between piston and cylinder . The engines had many endearing characteristics of smoothness and silence and were fitted by quite a number of firms in the middle twenties , but they did have the disadvantage that any lubrication failure destroyed the engine . The professors later turned their attention to optical instruments .
Valentine Page redesigned the Ariel range with saddle-tanks and new engines in 1927 and gave the old-fashioned firm a thoroughly modern image ( plate 26 ). An American , C. A. Neracher , marketed a revolutionary layout which he called the Ner-a-Car , in 1920 . It had a low , open frame , hub-centre steering like the front wheel of the contemporary cars , and a variable friction drive by way of transmission . Represented as proof against skidding , it was irreverently known as the motor-assisted mudguard .
In America , C. B. Franklin redesigned the Indian ( plate 16 ), which had quite a vogue in this country in the early twenties . J. V. Pugh produced a new range of Rudge-Whitworth machines with four valves , four-speed gearboxes and coupled brakes in 1925 . Proprietary engines led the way in motive-power design for a while , JAP , Anzani , Precision and Blackburne all offering thoroughly satisfactory high-performance overhead-valve engines very soon after the end of hostilities . Overhead camshafts for valve operation were first introduced by JAP in 1922 , to be followed by Velocette in 1924 , AJS ( a chain-driven design to which they remained faithful for thirty years - plate 23 ), Norton ( plate 28 ), Calthorpe , Humber and others all round about 1928 .
Villiers came out with a magneto incorporated in the fly-wheel - a cheap and compact design for utility lightweights , and good enough to drive all its competitors off the market . Most firms fitted it although Dunelt favoured a two-diameter " top hat "-shaped piston in their two-strokes , which gave an extra measure of pumping compression ( plate 24 ). British design was in a state of the utmost vigour . Some few of the varieties available to buyers have been mentioned but it seems almost invidious to single them out among so many . A few minutes with a motorcycle magazine of the twenties will give a better impression of the range then offered . Examples of most of them remain , however , and the discoverer must seek them out for himself .
Discovering Old Motor Cycles By T. E. Crowley N° 160 in the Discovering series First published 1973 Shire Publications Ltd. 12B Temple Square - Aylesbury Bucks - UK
