Sunbeam 1921 8HP 976 cc JAP side valve V-twin frame # 83670 engine # KT/21 494 The first Sunbeam V-twin is brought out in 1914; although the company claims that the 3 ½ HP single was also capable to pull a sidecar, a special sidecar model is thought necessary to keep up with the competition. This first V-twin model is powered by a 770 cc JAP engine, for 1915 a 798 cc Abington King Dick power source is used. The following year the twin is built using the 996 cc Swiss MAG engine, while from 1917 o ...
Vincent 1951/53 “Rapide Special” 1330 cc OHV V-twin frame # RC11684 engine # F10AB/1/7832 The first Series B Rapide was presented to the press on April 27, 1946. It was to be the base model of the post-war range, for Vincent-HRD made the decision to drop the successful singles and aim instead at the exclusive, high-performance end of the market with the only big British V-twin offered to the public after the war. The finish was to a very high standard in proportion to the cost of the machine, wh ...
Harley Davidson 1942 “U” 1209 cc side valve V-twin frame & engine # 42U2744 video: https://youtu.be/sG4m_zw15kc For 1937 the HD engineers redesigned the Big Twin range: frame and cycle parts of the newly introduced OHV ‘Knucklehead’ were used as the basis for the new 1209cc and 1303 cc models U and UH. An important new feature was the introduction (finally!) of dry sump lubrication. The “U” was the 5.0:1 low-compression type; the standard compression was 5:1. Power output of the U was 32.5 hp @ ...
BMW 1964 R 50/2 494cc transverse twin combination frame & engine # 636873 In 1955 BMW creates its R50, R60, and R69 models. These new models have a similar engine and the same shaft-drive as earlier models, but are fitted with modern swingarm rear suspension for the first time. The telescopic forks at the front of earlier models are abandoned though, in favour of the swinging or “Earles Fork” system. The cycle parts are finished in BMW’s signature black scheme set off by white pin striping. The ...
Sunbeam 1927 3½hp Model 6 ‘Longstroke’ 492 cc side valve frame # B1730 engine # J1778 After the Great War, Sunbeams first new design was a side valve of 77mm bore and 105.5mm stroke and a cubic capacity of 492 cc. At the works it was known as the ‘Longstroke’ to differentiate it from its short-stroke 85 mm x 88 mm ( 499 cc) predecessor. The new engine made a fantastic impression at the 1921 French Grand Prix on July, 24 at the Circuit de la Sarthe near Le Mans. The circuit length was about 17 km ...
Harley-Davidson 1924 “JE” 989 cc IOE V-twin frame # 24F4203 engine # 24JE4408 1924 is not a good year for the firm: the losses amount to almost $ 120,000 and the workforce is trimmed down from 2,500 to 1,000 employees. Sales in the USA have seriously diminished in the early twenties because of the competition of the cheap automobile. A positive thing is that export sales are still looking good. More than 6000 machines are exported oversees this year; this amounts to almost half of all Harleys ma ...
Harley-Davidson 1929 “29 C” 493 cc side valve single frame & engine # 29C2534 After the discontinuation of the 565 cc singles in 1918 the company tries to win customers in the 600 cc class with the flat twin model W Sport Twin, produced from 1919 up to including 1923. Sales are relatively modest, but it’s clear that especially in the European markets a small-capacity H-D will be a selling point, if only to act as a “starter model”. Consequently, in 1926 350 cc class models are brought out; the O ...
Velocette 1968ca Venom Thruxton 499 cc OHV frame # RS18486 engine # VMT1016C gearbox # 12/13181 The Thruxton 500 was a motorcycle endurance race for production based road machines, covering 500 miles and ridden by a team of two riders per machine. The event had started life as the Thruxton Nine Hours Race staged by the Southampton and District Club in 1955 and became the Motorcycle 500 Mile Race in 1958. It was to be the scene of several manufacturer inspired entries in the long distance product ...
Sunbeam 1932 Model 90 Road Racer 493 cc OHV frame # E13074 engine # NN6053 gearbox # BW1754F The Model 90 first appeared in the firm’s catalogues for the 1927 season. Sunbeam had tried to develop an OHC racer but that proved to be unsuccessful: the camshaft Sunbeam that appeared in 1925 was seriously lacking in torque and power because of problems with valve timing. The much more direct ohc mechanism necessitated a totally different valve timing, of which there was very little knowledge at the t ...
BMW 1976 R75/7 745cc OHV transverse twin frame & engine # 6020431 In the early autumn of 1976 BMW’s ‘/6’ series is replaced by the ‘/7′. The R90S-style fuel tank (adopted across the range) and redesigned rocker covers are distinguishing features while at the top of the range, 980cc R100 models replace the ’90’ series. The R75 probably offers the best compromise between power and economy, turning out 50 hp @ 6,200 rpm and having a petrol consumption of around 1:20. Top speed is 180 km/h and the d ...
Sunbeam 1914 3½hp 499 cc side valve frame # 2582 engine # 2575AN At the end of the 19th and beginning of the 20th century the Wolverhampton based firm of John Marston Ltd. has already earned fame for their superb bicycles. During 1911-12 it is decided to take up motorcycle manufacture: designer John Greenwood, who has already made his mark at the JAP and Rover companies, is contracted and will be responsible for most Sunbeam designs till the mid-thirties. As a consulting engineer for the engine ...
Harley-Davidson 1933 “VLE” 1217 cc side valve v-twin frame & engine # 33VLE2610 video: https://youtu.be/Ys8BBlSQxeo Harley-Davidson’s 1930 brochure describes the new 74ci (1217 cc) machine as “standing head and shoulders above all comers, with such startling new features as a 20% more powerful motor with Ricardo removable heads, interchangeable wheels, bigger tires, drop-centre rims, lower riding position, greater road clearance, automatic increase of generator output, drop forged forks, 100% st ...
Indian 1925 Scout 600 cc side valve V-twin engine # 55Y447 The successful Scout model boasts quite a few new features for the 1925 season: removable cylinder heads, larger valves, improved clutch with greater plate area and a different type of saddle suspension to insure greater riding comfort and a lower riding position. For better engine breathing wider valve cam profiles are used. The 1925 brochure shows a power chart that claims a 20% power increase for the 1925 Scout as compared to the 1924 ...
J-RAD 1921 frame # 1485 This unique bicycle was designed by Paul Jaray, an Austrian pioneer in aviation and streamlining. He is well known for his significant contributions to the development of the Zeppelin and for his streamlined automobile designs in the 1920s. It’s said that the design principles behind the J-rad were based on the shortcomings of conventional bicycles—issues Jaray observed while teaching his children to ride. For instance, the seat height allows the rider to start and stop w ...
Saroléa 1927 “23 O” 494 cc side valve single frame # 411 engine # 014821 video: https://youtu.be/lY_x1iI7d94 After the First World War Saroléa takes up motorcycle production with a continuation of the 1914 3½ HP single but soon a new 4 HP model with bore x stroke of 85 x 97 mm and countershaft gearbox is presented. The engine and primary drive cover of this model bear a striking resemblance to those of the Triumph Model H and the Saroléa is, like the Triumph, also equipped with a Sturmey–Archer ...
Harley-Davidson 1930 model DL 742cc side valve V-twin frame # 123078 engine # 30DL2747 The HD company introduced the side valve concept for the V-twins for the 1929 model year when the 742cc model D was introduced. The model D is sometimes referred to as the “three cylinder Harley“, because of the remarkable vertical position of the dynamo: in a cost saving idea, the new motorcycle was designed to use the existing frame from the 350cc Model B single. This required the generator to be mounted ver ...
FN 1931 M 70 C “Sahara” 346 cc side valve frame # 69284 engine # 19209 At the end of 1923 FN presents a 350 cc single cylinder ohv with unit construction engine. This model, the M60, is the start of a successful new line of models in a period in which the heavy and expensive four cylinder is quickly loosing ground. Two years later a bigger 500 cc brother is brought out, the M 67. Shortly after that FN four cylinder production is finished. The ohv singles are very successful, but the factory real ...
Harley-Davidson 1920 Model F 989 cc IOE V-twin engine & frame # 20T9120 video: https://youtu.be/FqXgDkCt_PU The 1920 catalogue gives some excellent arguments why one should choose a Harley-Davidson: ”Enthusiastic Harley-Davidson riders have often pointed out that it actually costs less to ride a Harley-Davidson than to walk. Considering the present cost of shoes, whether one figures his time worth anything at all or not, there is little doubt but that is true. But in figuring the cost of driving ...
Excelsior 1918 Series 19 998cc IOE V-twin frame # 18923 engine # 85883 video: https://youtu.be/w-L55_ON3wg 1911 was a landmark year in Excelsior’s history, for the firm was acquired by bicycle maker Ignaz Schwinn and introduced its first v-twin model that year. In 1913 a twin within the 61 ci displacement was offered with all-chain drive, while two-speed planetary transmission and a leaf-sprung, Indian-style front fork were two of the following season’s innovations. Alongside rivals Harley-David ...
Harley-Davidson 1934 “VFD” 1217 cc side valve V-twin frame # C188 engine # 34VFD1663 There are various new features for the 1934 model year, many being mainly cosmetic. The cylinders are modified and new tank graphics with “Flying Diamond” design are introduced. Frames and forks are now completely heat treated and the company states that this “adds full fifty per cent more strength”. The mudguards get a new shape and a new “Airflow” tail lamp is fitted. 1934 wil be the only year of the upswept “ ...