sporting machines on test

SPORTING MACHINES ON TEST—continued.

of one kick from cold, without flooding and astride the saddle.

The sporting Amac carburettor gave good results on the whole, but possibly an improvement might be effected by a variable jet having a small range of openings. I am not in favour of variable jets as a rule, but in this case should have liked an opportunity of making some tests in this direction.

The Sunbeam patent oil-bath chain cases were fitted to this model, but actually the Longstroke is sent out with an ordinary chain guard for the rear wheel. I think it would pay to sacrifice a little weight and accessibility by having an oil-bath chain case fitted as standard. Special comment is called for with reference to the gear-box, which besides being extraordinarily silent in operation, permits of very quick changes. This may be attributed to the method of employing dog clutches, actuated by the Sunbeam rack-and-cam motion. The only criticism I have to offer concerning the gears on the machine I tested, was the difficulty in engaging the first gear quietly from a standing start, but I cannot

MAJOR H. 0. D. S8AGRAVE ON THE DARRACQ AT MIRAMIS.

The Oxford Motor Club Handbook.

We have received a copy of the above mentioned Handbook for 1925, which is extremely well produced and full of interest, not only to Club members but to motor cyclists and motor car owners in general, though primarily intended for the former.

We give below an extract from the 1925 programme from which it will be seen that the Club is a very live organization.

Fri., May 1st May Morning Run.

Sat., May 2nd Surbiton Team Trial.

Sat., May 16th B.M.C.R.C. Race Meeting at Brooklands. Sat., May x6th Herts County A. & Aero Club Hill Climb,

Aston Hill.

Sat., May 23rd A.C.U. South Midland Centre Hill Climb. Subject to alteration.

believe this is anything but a slight misadjustment, which should be easy to correct. The ratios fitted on the machine I tested were as

follows : 7.0: and 10.5, which suited the course admirably. Other ratios are optional.

On some 3i h.p. machines, one feels the need for a fourth gear, but on the Sunbeam the ratios are comparatively close and this, coupled with a high engine performance, renders the extra gear quite unnecessary, except perhaps for sidecar work with a heavy passenger. Slow top gear running, say through a io mile limit, is very attractive, since with the spark fully retarded, it is possible to throttle down: to 6 or 7 m.p.h. without any snatch.

The tank holds about iI gallons of petrol and a quart of oil, which is quite sufficient for the engine capacity, but with the big jet I used the engine is naturally greedy, though the average consumption was about 5o m.p.g.

On several speed tests I reached between 73 and 74 m.p.h., and in general terms formed an extremely favourable opinion of the model for all round efficiency.

Speaking of Brooklands as a venue for sporting events on an even more extended scale than at present, there seem to be splendid opportunities for developing the unoccupied space in the middle of the track as a sporting course of more that ordinary interest. If only all the motoring clubs and organisations could be persuaded to co-operate there would be no anxiety for the future of speed trials under road racing conditions.

By introducing the novelty of including the roads and test hill at the Brooklands Track in their High Speed Reliability Trial, the Junior Car Club Committee have rendered a big service to the sporting motorist, and we shall probably see further developments in this direction in the near future.

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