SPOTING MACHINES ON TEST

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SPORTING MACHINES ON TEST.

The 348 c.c. O.H.C. VELOCETTE.

By THE EDITOR.

LAST month we had the pleasure of reviewing a machine built specially for road racing—but which had not actually performed in any race. This month however, we are lucky enough to be able to give readers our impressions of a machine which has proved its mettle in competition with the world’s finest riders and mounts. The machine in question is the o.h.c. Velocette, on which H. J. Willis averaged 64 m.p.h. in this year’s Junior T.T., a speed which enabled him to finish second, behind the redoubtable Freddie Dixon. The performance of such a machine in ordinary hands is always doubly interesting, firstly on account of the comparison between its behaviour and that of the standard production, and secondly because of the ever intriguing question of the suitability of a T.T. mount for everyday use.

Taking the second point first, as being the most important, it is always difficult to disabuse the ordinary motorcyclist from the belief that a T.T. motorcycle is of necessity harsh and intractable at touring speeds, drinks petrol, is uncomfortable and generally behaves in a thoroughly ungentlemanly fashion.

Whatever criticisms may be levelled at the organisers of the Tourist Trophy races, it is now obvious that several wise regulations recently introduced have resulted in a racing machine which cannot possibly be convicted of the above faults.

Foremost among these regulations is the compulsory use of standard fuels, which automatically prevents any freakish compression ratios and fantastic fuel consumption, while the 7th lap,—also recently introduced, demands even greater robustness of mechanical parts and renders comfort a sine qua non, if success is to be hoped for. The I.O.M. machine therefore will generally be found ideal for fast road work, and at the same time may be relied upon to behave itself with reasonable decorum in traffic and in the ” peaceful ” thoroughfares of “Suburbia.”

The T.T. Velocette is an excellent example of what a thoroughbred roadster should be, having speed enough for the world’s greatest road races, combined with several extremely desirable ” traits ” such as uncanny mechanical silence and great docility at low speeds.

Lest readers should conclude that these are the machine’s only virtues let us hasten to state that others will be disclosed in the course of these notes, which we fear will degenerate into a series of eulogies, but in the meantime let us return to point one, raised at the head of this article.

It is common knowledge that the K.S.S. Velocette is definitely guaranteed to do 80 m.p.h. We ourselves found that the special T.T. model was capable of approximately 85 m.p.h. on the level, but certainly not Imre, so that owners of the K.S.S. model have the satisfaction of knowing that the makers have put almost “all they know” into the standard production. Apart from a few very minor detail differences the T.T. machine is identical with the 1928 K.S.S. model—the most obvious differences being the footrest mounting and the absence of a kickstarter, features which do not detract from the utility of the machine in any way.

On the Manx Circuit.

In the course of our test of the Velocette we covered a good many miles in the Isle of Man, on roads which the machine was designed to cover at maximum velocity. Now the Tourist Trophy course is not exactly smooth, even at fast touring speeds, and each year as more and more power is extracted from engines, it becomes increasingly obvious that the steering and road holding of many machines leaves much to be desired. It is an education in itself to watch back wheels on even such a stretch as the straight through the start, while the bhaviour of some machines on Bray Hill causes strong men to shudder. One more point should be emphasised before finally referring to the steering of the Velocette and that is that the writer had broken a collar bone exactly a fortnight before riding on the Manx roads and his arm could not he raised above handlebar level. Naturally this weakness would have seriously jeopardised control on bumpy roads if any undue effort were required; the superlative steering of the Velocette at once becomes apparent when it is stated that at no point on the T.T. course was it necessary to ease the throttle owing to bumps. If the tortuous nature of the road demanded alteration of the throttle opening (as it frequently does), this was naturally done, but if the road were sufficiently straight to allow full speed, a slight extra pressure of the knees on the “George Dance” knee grips was quite sufficient to retain perfectly normal control. The fore part of the machine progressed in a perfectly straight line under all conditions without dither or wobble, and even back wheel bounce—that designer’s bugbear—was

noticeably absent except on the really atrocious bumps. Even on the worst sections the back wheel only jumped slightly in a vertical plane and exhibited no tendency to wag.

To sum up the steering and road holding, we can give no finer testimony than to say that it was possible to descend Bray Hill “flat out” and to add that we discovered later that several layers were missing from the steering damper and although we thought we had adjusted it, its aid to the steering was purely moral !

Speed on the Gears.

We have already mentioned that the maximum speed on cop gear was beteeen 80 m.p.h. and 85 m.p.h., and we estimated that the speeds on first and second gears were 45 m.p.h. and 65 m.p.h. respectively. On the climb from Ramsey to the Bungalow speeds between 50 m.p.h. and 60 m.p.h. were possible on second gear, according to the variations of the gradient while the acceleration on bottom gear after corners, was very satisfactory. At one point only, namely the Gooseneck, the machine appeared somewhat overgeared and laboured slightly when accelerating ; possibly this was due to our somewhat slow and inadequate method of negotiating this corner, which for the sake of the uninitiated we will describe as a right hand bend, becoming sharper as it goes on. and arranged on a sharp up gradient !

Cornering is at all times more a question of the man than the machine, some heroes or lunatics (according to one’s attitude to such matters), can bank the most mi. stable vehicles at impossible angles, while others are incapable of allowing a machine to depart from the vertical.

The Velocette is a machine which induces even the most timid rider to indulge in quite respectable cornering, such is the feeling of ease and controlability inspired.

The footrests were placed well out of the way of the road, and incidently in a very comfortable position, so that the bicycle could be leaned over with confidence on any reasonable surface, while only the most treacherous grease caused any skid.

The rear brake was applied by a conveniently situated left toe pedal, its operation did not necessitate removal of the foot from the rest, while the stopping power was good, provided sufficient pressure was applied. The front brake was better in comparison, and was operated by a very long inverted lever on the right bar ; the anchor plate was fitted with the special flange for draining water away from the shoes and drum, a useful feature on all Velocettes. The gears were changed by a conventional spring lever in a very compact quadrant on the tank—the movement from one stop to the next being delightfully short, but what contributed still more to easy changing was the extreme lightness of the clutch control. This small item makes an enormous difference to driving comfort, the clutch on the Velocette could be withdrawn with one finger and it could be re-engaged smoothly, progressively and yet positively in spite of a rather high bottom gear. As a pure experiment we once performed a standing start on top gear, when by careful manipulation of clutch and throttle it was possible to execute a perfectly smooth” get away” without snatch or pinking—such is the flexibility of the engine and the sweetness of the clutch.

Advanced Design.

In the foregoing notes we have endeavoured to expound the virtues of the Velocette as a machine to ride ; students of design, however, will find much to interest them, as the machine embodies some extremely clever features which contribute in no small measure to its excellent performance. The instantaneous success of the o.h.c. Velocette in the

T.T. races, at Brooklands and in the hands of private owners throughout the world is too well known to need repetition here, and is not surprising when it is remembered that the Velocette designer is acknowledged to be one of the cleverest men ir the industry, while the firm’s long experience in the manufacture of the very successful

two stroke, ensures accuracy of workmanship in the later model.

The prices of the o.h.c. model vary from £58 for the popular model to £75 for the K.S.S. with an 80 m.p.h. guarantee, while the makers are Messrs. Veloce, Ltd., Hall Green Works, Birmingham.

R.O.P.

In view of the recent outburst in the daily press, together with the publication of ” statistics,” it is interesting to learn that the sales of R.O.P. Motor Spirit are tiot on the decrease.

On the contrary, the sales of Motor Spirit by this firm up to the year ending September 30th, 1927, were actually 52% in advance of the sales in the corresponding period last year ; and the sales of kerosine were 72% higher in the corresponding period.

The import figures this year are misleading, as such an enormous amount of oil was brought in during the last three months of 1926, owing to the opening of new storage installations, that imports have been limited this year.

R.O.P. depots are being rapidly established throughout the country, and the distribution of this excellent spirit will be greatly increased in 1928.