THE TOW-CARBURRETTER B.M.W. 700

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THE TWOCARBURETTER B.M.W. 700

An Energetic 697-c.c. Air-Cooled, Flat-Twin, All-IndependentlySprung Sports Coupe from Germany

BAYERISCHE Motoren Werke of Munich built up a fine reputation for high-quality fiat-twin shaft-drive motorcycles of notable longevity. To meet economic demands after the war they introduced the Isetta 3-wheeler, later made as a 4-wheeler, a single cylinder ” bubble-car ” that survives when so many vehiclesin this class have been discontinued. B.M.W., apart from their luxury ears, then turned to a normal 700-c.c. rear-engined small car, which is now available here in saloon and coup& form, the latter with two-carburetter engine, through the B.M.W. Concessionaires in Brighton.

Enthusiasts in England had their first chance to assess this fast little German car when Herbert Linge brought one to Silverstone last year and won the up-to1,000 c.c class of the B.R.D.C. British Empire Trophy Production Touring Car Race at 6946 m.p.h., trouncing Whitmore, Aston, and several other well-known drivers in B.M.C. Minis. He actually finished third in the entire race, behind the 3.8 Jaguars of Parkes and Graham Hill!

I recently drove the Sport coupe version of the B.M.W. and came to the conclusion it is great fun, a modern cyclecar of sparkling performance, which gives the impression of being well made and likely to carry on the B.M.W. tradition of quality and long life.

Although, when you open the” piano-top “covering the engine compartment, there is little to be seen apart from the elaborate ducting round the fan-cooled horizontally-opposed cylinders, two Solex 34 PC1 carburetters taking air through a remote cylindrical air-cleaner and an individual coil for each of the aforesaid cylinders (which keeps the wiring very simple!) this is no reason for disparaging this unusual engine. This remarkable 78 x 73 m.rn. (697-c.c.) engine with pushrod operated inclined o.h.v. runs up to 7,400 r.p.m. if pressed, can be habitually extended to 6,soo r.p.m. and develops 40 (net) b.h.p. at 5,800 r.p.m. Although it is noisy at low speeds, as the pace mounts above 60 m.p.h. it not only smooths Out to become a very unobtrusive power unit but is appreciably quieter. The compression-ratio is 9 to i but too-octane fuel is not necessary and the engine starts reasonably easily, doesn’t run-on and feels completely ” unburstable “. This B.M.W. coup& is a compact little car but its performance is such that I had difficulty in believing that it has a Capacity of under 700 c.c. It is, indeed, capable of reaching a genuine

70 m.p.h. (approx. 5,300 r.p.m. in the 4.56 to top-gear) very easily indeed, and along a motorway or similar road, speed will build up by another 12 m.p.h. This is definitely a sports car, in which the revs. should be maintained at between 5,000 to 6,500 r.p.m. to get the best results. The makers suggest maxima in the gears of 25,44 and 66 m.p.h. but if the red mark on the tachometer is ignored these can be pushed up to 34,56 and 75 m.p.h. on the speedometer. The ratios are 14.48, 8.68 and 6.23 to 1 respectively.

The need to keep the engine revving results in acceleration in any one gear that is not especially impressive but if the gearbox is used the B.M.W. Sport will see off normal B.M.C. Minis up to 6o m.p.h. and beyond. Yet there is real flexibility in top gear, for which the prominent rubber engine mountings and good balance of a flat-twin are doubtless responsible. Few cars can be as easy to drive as this little B.M.W. Visibility is excellent, forwards or over the modest tail-fins. The rack-and-pinion steering, needing just over 2i turns, lock-to-lock, is light, accurate and vice-free, with mild castor action. The stubby, rigid central gear-lever comes readily to hand, controlling

a 4-speed, all-synchromesh gearbox, with reverse easy to engage beyond second. It is necessary to move the lever precisely and the action is spongy, .reminder that the lever is operating via lengthly controls, but the change is quite a pleasant one. It is possible to crunch bottom gear, if the driver is clumsy.

The brakes are insensitive, so that intended progressive stops are apt to become fierce retardation, but they give retardation fully in keeping with the available performance, given a hearty pressure on the pedal.

The suspension is interesting, because this is a rear-engined car without the expected swing axle i.r.s. Instead, trailing arms are used at the back, the drive shaft having rubber universals, and the suspension medium being coil springs. Front suspension is also by coil springs, with leading links, and Boge hydraulic shock-absorbers are used all round, with an anti-roll bar at the back. The cornering tendency is definite and quite pronounced oversteer, and this is evident also by the manner in which the car is easily deflected from a straight course, by camber or cross winds. Nevertheless, road-holding is of a high order, the wheels seldom losing grip until the tail slides, which the quick steering easily controls. However, really rapid cornering introduces roll at the rear-end which leads to untidy correction of a slide, and consequent ragged cornering. Through all this the 5.20 X 12 Continental ” Schlauchlos “tubeless tyres never protest.

The ride is apt to be lively without being uncomfortable unless bad roads are negotiated at speed. There is little head-room to spare for a driver of average height, and a tall driver’s head would contact the roof under these conditions.

This little B.M.W. gains high marks for general convenience. For example, although compact it has a generous-sized back seat the back of which folds, or can be completely removed if required, with a parcels space behind it and the front boot will Swallow much luggage, the spare wheel being mounted vertically at the front of it. The control arrangements could hardly be more simple. Confronting the driver are the Vdo tachometer reading to 8,000 r.p.m. and the matching 95 m.p.h. Vdo speedometer-cum-distancerecorder. Between these are four warning-light windows. To the left are a cigarette lighter and knob for wipers-cum-washers. To the right two similar knobs look after lamps-cum-facia lighting and rheostat control of the latter. Convenient stalks protrude from beneath the steering wheel, that on the left dimming the headlamps or, pulled upwards, flashing a full-beans daylight warning; that on the right actuates the self-cancelling direction ‘flashers or, pulled upwards, the horn. Under facia controls operate the parking lamps and provide for distribution of ventilation.

Two tiny quadrant levers behind the gear-lever respectively operate the choke and vary the degree of interior heat, and a little panel below the facia contains an Instantly accessible reserve fuel tap (labelled ” Auf ” — ” Zu ” — ” Res..”) with a pull-out knob for warns air distribution beside it. Ingenious features — the petrol gauge is like a ribbon speedometer in reverse, showing diminishing readings until an all-red indicator warns that the reserve supply is needed (this gives about 24 miles’ supply) and the ignition-corn-starter key is 00 the floor ahead of the gearlever, so arranged that neutral must be selected before the engine can be switched off, after which the lever is locked in this position. That this is a truly small car (wheel base 6 ft. 111 in.; weight unladen 121cwt.) is evident from the intrusion of the front-wheel arches, causing the pedals to be strongly biased to the left, but this does not seem inconvenient in practice. More serious is

lack of space in which to rest one’s clutch foot. The treadle accelerator needed a very firm pressure to open it fully, possibly a safeguard against too eager revving up. There are good Hella lamps, a small interior lamp above the off-side door with courtesy action, twin non-swivelling vizors and an enormous lidded ashtray on the facia sill.

The small separate front seats, with squab angle adjustable by means of cams, are specially shaped for firm support of the thighs and although they are hard a stronger criticism would be that they are rather low-set. The sliding adjustment controls are too close to the doors. Generally I found the B.M.W. 700 only moderately comfortable.

At speed wind-noise is commendably low, and although the engine has a busy note when accelerating hard, and the small wheels transmit road-noise over certain surfaces, the combined cacophony is no worse, if of a different nature, than that to be endured within other very small cars.

Both front and rear boot lids have to be propped up manually. A push-button opens the rear lid. The door windows don’t open fully but wind almost down with three turns of very flexible plastic handles. There are no J-lights but the rear windows open as vents. I liked the exterior door handles, whereby you press a button and the handle comes out Conveniently to hand, the lock works well, and the small interior handles move back to open the wide doors. There is mild padding under the scuttle but no real crash padding. The central hand-brake lever is well placed and for access to the back seat side levers are operated to permit the front-seat squabs to hinge forward; they are otherwise locked, a good point, but not much space is allowed for getting into the back compartment. An exterior mirror supplements the interior rear-view mirror. Horn. and wipers function only when the ignition is ” on “, which I dislike.

Slightly crude is the unsheathed steering column terminating in a flexible joint within the driving compartment. The doors have substantial interior grip-handles and the facia incorporates an open cubby hole.

The gear-lever has a rubber fume-excluding sleeve and a good feature is a rubber shield to prevent spilt fuel from running past the front filler into the luggage compartment. The tank holds just over seven gallons and I averaged 344. m.p.g. so the range is approx. 240 miles inclusive of the reserve supply. Driving gently 42 mpg. was possible and 36 was normal on main-road runs. The body is free from rattles, the plastic/fabric upholstery is smart and looks durable, and I like the rather aggressive appearance of this little sports coupe, with its non-tapering wide body lines. The smart B.M.W. badge is displayed front and back and on the wheeIknave plates but of the motifs at the rear only the word

coupe discloses that this is the quick 5 (gross) b.h.p. per-litre version. The wrap.-round side lamps are sensible. In the engine compartment is evidence of much felt-sound insulation on airducts and push-rod covers, the Sonnenshein battery is accessible and the dip-stick available by unscrewing the very Small, deeply threaded oil filler cap. That there is nothing wrong with the breathing Of this flat-twin is evident by how clean it keeps and the fact that not a drop of oil had been used after 580 miles.

I found this little B.M.W. cyclecar good fun. Over 80 m.p.h. from 709 c.c. is not to be sneezed at, especially with excellent acceleration to 70 m.p.h. which makes passing slower vehicles a safe accomplishment. The flat-twin engine is not a deterrent to the charm of the B.M.W. 700 and I need hardly reiterate the advantages air-cooling confers, not least of which is a quiet system of interior heating (very adequate in the case of the B.M.W.) — and the fascinating sounds the cylinders make while cooling off! An experienced friend who drove it expressed the view that it would take a Cooper-Mini to catch it over cross-country journeys, although the B.M.C. Mini handles in a superior manner. Either as serious transport or as a handy second-car of individual character, I commend this B.M.W.

The Sports version costs £65i which Import Duty and p..t. unfortunately inflates. It is handled by B.M.W. Concessionaires Ltd., New England Street, Brighton, Sussex.—W.B.