SPORTING MACHINES ON TEST.
By ARNOLD RADCLYFFE.
FIRST impressions are not always the best, and I must acknowledge that even with an empty sidecar the Rudge called for unfavourable comment several times within the first hour of my run. Wherefore I will unburden myself of all the bad points at the start.
Several times during my passage through London I missed the second and third gears in my attempt to make a quick change and for a long time I was at a loss to effect such a change as one can accomplish on another well-known four-speed machine. This inability on my part was due to the lack of a positive stop on the gear quadrant for any gear except top, when changing up, and bottom when changing down. Eventually, I came to the conclusion that it was impossible for any one not acquainted with the Rudge quadrant to obtain a fast and silent change during the first hundred miles or so.
Nevertheless a slow change, namely, one in which you moved the lever into position instead of pushing it in, was very easily accomplished, and a more delightful method of changing gear I have yet to find, but it does not enable one to overtake that lorry in front with quite as much celerity as one could wish for. At the same time, the four-speed box does not necessitate one getting into top gear before any speed is obtained. I estimated that 35 m.p.h. was obtained on third.
After a long week-end with the Rudge I am still wavering as to whether I should prefer the more orthodox type of quadrant : I think perhaps the manufacturers could compromise by making the notches deeper and more positive. My next grouse is steering wobble with an empty sidecar ; true enough this is quite common enough not to warrant mention, but as it is easily cured by the fitting
of a small steering damper, I think it ought to be standardised, as a sidecar machine is driven nearly as much without a passenger as with one, and the wobble, which was so bad in this case as to necessitate both hands being used all the time at speeds of over 20 m.p.h. But here let me say that with a passenger it would be hard to imagine a better balanced outfit, and there was no ” pull” noticeable, even when riding on the left hand camber of the road, and the wobble absolutely vanished.
The riding position was correct and comfortable, but the saddle was hopelessly inadequate for anyone over about fourteen years old. It is, unfortunately, a growing tendency for manufacturers to fit undersized saddles, presuming, I suppose, that the purchaser will immediately invest in a super saddle of the Terry type, and that it would be waste for them to fit a good saddle to start with.
At the same time, one gets a lot of refinements for &2 when one buys a Rudge 350 c.c., and a saddle can be changed, whereas cheap hubs and such like fitments are absent on this machine, and it is better to get one’s • value in the machine rather than on it.
My last grumble is perhaps one against myself, but I relate it if only as a warning to others.
I was so preoccupied in threading traffic and getting the feel of the machine, that I had forgotten to watch the oil indicator on the mechanical pump, and it was not until I was nearing Byfleet that I remembered it. I had been. thinking that there was too much noise down below, but I had put this down to the gear for the four valves, which I thought would naturally be a bit noisier than the ordinary o.h.v. This is noisy, but not excessively so, and the extra noise was occasioned, as I found out later, by the complete absence of oil, which resulted in a engine seizure, culminating in a skid of nearly forty yards dead straight.
On examining the pump I found that, although I had a full oil tank (situated by the way, aft of the rear down tube), the pump was dry, and this is where the warning comes in ; never let your oil tanks go dry before filling up, as this will occasion an air block in the pipe, and it is a messy business filling the lead pipe with oil to start the pump functioning again. Putting the pump at maximum it soon started to work, and the difference in the engine was of course very marked ; here I might mention that the above incident speaks well for the construction of the Rudge engine, and is, of course, a sound argument in favour of the roller bearing big end. Having mastered the gears and the oil, the ensuing mileage traversed became an enjoyable ride, and I kept on forgetting that I was only mounted on a 350 c.c. machine. So much so, that when on returning to
Staines from Brooklands, I heard a roar and saw a flash of white passing me, I quite naturally opened out and went after the fire-eating monster that had just stirred up the dust. I felt inclined to drop down to touring speed again for the white and polished brass leviathan was nothing less than the famous “Mere.” I did not shut off, however, and with the little Rudge singing to me, now on top, now on third, I managed to keep the one time pet of Zborowski in sight until Runnymede was reached, a matter of some ten or twelve miles. Along this expanse the “Mere.” just vanished, but I felt very proud of the little engine that for ten solid miles had been all out and had never murmured. Before I turn to the engine details, I would mention that hills and ” colonial sections” were both included
in my test and bottom gear was hardly ever needed. The front forks with their enclosed spring acted silently and unobtrusively, bounce was absent, and for one I can say that shock absorbers would be a superfluity.
The brakes act on false rims on both wheels, and the shoes are of good dimensions, which should eliminate overheating. Braking efficiency was high and neither brake was pierce, both acting in as perfect a manner as one could desire. The front brake would not stop the machine dead, and could be applied with as much force as possible without using the back brake as well. This worked well : the whole outfit could be brought to a standstill without effort. Starting was easy when the right mixture was ascerThe clutch—dry plate—was sweet, but quite positive, and gear changing could be effected without touching the throttle. Talking of the throttle, would that every machine was fitted with the Senspray carburettor ; with this instrument it is possible to obtain any conceivable mixture that is necessary under changing conditions of weather, quality of petrol, acceleration and load. During the whole of my test I was unable to find any signs of a “dead spot,” and the carburation appeared perfect from the minimum speed to the maximum. It is now, however, a ridiculously easy instrument to control at first acquaintance and yet it can, with suitable setting of either lever, be converted for traffic purposes into a one-lever carburettor ; but here again this should not be acted on. too much, as it would undoubtedly influence the petrol consumption. This, by the way, worked out satisfactorily, and the petrol tank (of sensible proportions and holding two gallons) was not empty when I finished my run of about 120
ENGINE.-7o mm. by 90 MM. stroke : develops ro b.h.p. The four-valve mechanism is neat but inclined to be noisy. This is only noticeable at very low engine speeds : at higher speeds it merges into the general hum and virtually disappears.
The magneto (or in this case the magneto unit) is sensibly mounted high up, and positively driven ; the oil pump being driven from an extension of the main gear wheel in the timing case.
Silencing arrangements are efficient culminating in a pleasant note, hardly audible by the rider.
The gear box has double helical teeth always in mesh, which tends to and does produce a slight hum ; this is only just noticeable and is not unpleasant.
The sidecar chassis is interesting, embodying a flat-spring steel axle with underslung Cee springs at the back and coils in front. The body itself is comfortable, and a tall person is easily accommodated, but a small a djustable ” stretcher” should be provided for the feet. The windscreen is mounted in a really sensible position, so that the passenger gets the benefit of it and not the draught caused by it, as is usually the case, nevertheless it mitigates against easy entrance and exit ; perhaps a quick clip on the near side of the detachable covering would be a suggestion worth adopting. To the man with a small pocket and a desire for something reliable and speedy, this little outfit should appeal immensely, especially as the price has now dropped to Li42, without the sidecar, which is listed at &7
A German Sports Machine.
A photograph reproduced on page 453 represents the B.M.W. Sports machine, which is built by the Bavarian Motor Works, near Munich. The rider, Herbert Gumprecht, is an amateur, who graduated at Oxford University since the war, and intends taking part in competitions in this country.
The engine is rated at i6 b.h.p., and has horizontally opposed cylinders, unit construction with a three-speed gear-box and shaft drive. The triangulated frame is also of interest and in all respects the design is of a very advanced character.
Another Darracq Win.
George Duller, on a Darracq, won the 300 Mile Race for the Grand Prix—reserved for cars of 1,500 c.c.covering the distance in 3 hours II minutes 45 seconds.
Count Conelli, on a similar machine, was second, and Major Segrave, also on a Darracq was third.
At the end of the race Count Conelli attempted to pass Duller, who, however, swerved, and Conelli’s car overturned. The driver was dragged a distance of fifty yards, but he was able to get up without assistance, having only received superficial injuries.