The History Of Vincent Hrd Motorcycles-stanley博士的家2

Motorcycles Phillip Vincent was a determined man who had firm ideas on how a motorcycle should perform, and more importantly, how a motorcycle should be built. He had studied mechanical science at Cambridge University and had a poor opinion of many features of the contemporary machines. In the 1920s, he built his first motorcycle. Like all others, it had rear suspension with a triangulated pivoted fork and the springs were mounted beneath the saddle to work against the upper frame. It had a Swiss Mag engine, a Moss gearbox, Webb forks and Enfield hubs. In 1927, at the age of 19, he decided to go into business making motorcycles. After taking advice from Arthur Bourne, he purchased the established HRD name from the OK Supreme Company. The HRD name may have only been 3 years old, but the name Howard R Davies was well known, as he had tied for second in the 1914 Senior TT, been reported as killed in Action in 1917, and had won the 1921 Senior with his 350 AJS. After forming his company, he was second in the Junior and won the Senior in 1925. With this background, the models were in demand and were brought out before the name went onto Vincent. Davies was rather surprised at the Motorcycle that resulted, as the fine rigid frame was gone, so resulting in a machine that was totally changed other than in the use of a proprietary engine. By 1930, Vincent HRD was known as makers of high class, hand built machines. Thanks to the depression, the company could not have chosen a more inauspicious time to use rear suspension, as this was a major point against the marque. There was great prejudice against such things at that time, and the statement that all TT winners used rigid frames countered any engineering reasoning. Vincent sales were minimal, and like the Brough, they were a club for the dedicated. They gradually improved and, in 1930 went to Olympia with a range powered by JAP engines. For touring there were the 490 and 600cc side valve engines, and for sporting use, the same size OHV engines. A pair of racing JAP engines cultivated the competition rider and finally there was the 350cc Grass Track racer. The latter was significant to Vincent sales, and in 1930, the sales were 36, which was up 50% on 1929. This figure progressed to 48 in 1931 and in the same year, the company began to indicate Rudge Python engines as an option after experiencing a run of troubles with the JAP units. In late 1931, Phil Irving joined the company and was immediately involved with the new frame. His knowledge was to complement the innovations that came from Vincent to produce good working motorcycles. The new frame set the format for the pre war Vincent and had a single tank, seat and down tubes. The engine was part of the structure with small front plates and massive rear ones. The latter surrounded the gearbox and provided the mounting for the rear fork pivot and its taper roller bearings. The rear suspension springs and dampers went beneath the saddle, and loaded by the triangulated rear fork. Damping was provided by friction material between the inner and outer spring box covers and could be adjusted by the external clamps. In this frame, the customer had the choice of a 490cc JAP or a 499cc Python engine in standard or sports form. For those who preferred the older style, there were five further models listed, but hardly any were sold. Phil Vincent was let down in the 1934 TT, and with Rudge units becoming hard to get, he decided to make his own. He was to exhibit it at the next show; he had only four months to produce it. He succeeded, and the design set the style for all his future engines. The valve gear was what set Vincent apart from the others, and began with a camshaft placed high up with push rods spayed out to run parallel to the valve line, which allowed the rockers to run straight across the head to the valves. Another unusual feature was that each valve had two guides and the rocker located on it between them. The hairpin valve springs went above the rocker, and well away from heat and were exposed. The top of the valve stem was threaded and the upper spring holder screwed to it. Two external pipes supplied oil to the rocker chambers, and these were the subject of criticism by the press, but Vincent pointed out that others relied on grease guns. About the Author: 相关的主题文章: