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STADION  S 1 moped.

Much is being asked from the moped in these days. Whereas a few years ago the majority of buyers were quite happy with an auxiliary engine fitted to a bicycle with the sole purpose to save pedalling, today they demand a moped, a motorised two-wheeler of its kind and not just a bicycle with an auxiliary engine.  Nowadays the moped must not only be attractive and comfortable, but it has to meet a number of very exacting requirements and yet be as modest as possible in respect of servicing and the technical knowledge of its owner.  The STADION S 1 moped is the perfect answer to all these demands.

It has a simple open tubular frame.  Front wheel suspension is by bottom links with rubber as suspension element. The wheels have light alloy rims and are equipped with well dimensioned full width hub brakes. The rear chainwheel remains in the fork when the rear wheel has been removed.  The rear chain is protected by a smart chainguard. Attractively shaped mudguards offer good protection against dirt to the rider. The saddle is very comfortable, well sprung.

The driving power is supplied by a two-stroke single cylinder JAWA engine, model 552, with in-built pedalling mechanism. It is fitted to the frame in three points, two of which are formed by the engine plates and the third is located on the carrying frame tube.  The handlebar controlled two-speed gearbox is of unit construction with the engine. The engine has the typical shape of all JAWA engines and is marked also with the characteristic solidity of the engines of the make and alike with their other qualities, simplicity, reliability, long life and little claim as to maintenance as well as economy of operation. The light alloy cylinder has a cast iron liner, the cylinder head being also light alloy.  This is equipped with a decompressor for easy starting.  The crankshaft is supported in ball bearings, two of which are on the R.H. and one on the L.H. side. The connecting rod is supported on the crankshaft by means of a single row roller bearing. The suitably dimensioned flywheels ensure quiet and well balanced running of the engine.

The engine power can be limited in the upper range of revolutions by a simple means to comply with the values prescribed by the traffic regulations in certain countries.  This limitation, however, does not affect unfavourably the torque in the lower revolution range.  The engine is provided with a single exhaust pipe on its bottom side, to which a detachable exhaust silencer is fitted. Ignition is by flywheel magneto. The ignition coil is located in the magneto stator.  The JIKOV 2912 carburetter is flange fitted to the opening of the inlet port.  It is of monoblock construction. The clutch is on the L.H. end of the crankshaft and runs in an oil bath.  It has two steel plates and two asbestos lined plates.  The primary drive is by gears and its ratio is 4,75 to 1.  The final drive is by chain, the ratio being 2,69 to 1.

Technical Data

 

Engine

two stroke, air cooled

Number of cylinders

single

Bore

38 mm

Stroke

44 mm

Cylinder capacity

49.8 cc

Compression ratio

6.8 to 1

Fuel tank capacity

0.7 galls (3 litres)

Maximum speed

25 mph (40 kph)

Weight - dry

77 lbs (35 kg)

Carrying capacity

176 lbs (80 kg)

Carburetter

JIKOV 2912

Tyres

23 x 2 in.

The controls are located on the panel type handlebars. On the L.H. side of the handlebars is the clutch lever, the gear change control of the two gears and the decompressor lever.  On the R.H. side is the throttle twist grip and front brake lever. The rear wheel brake is controlled by back pedalling.  The moped is equipped with a headlamp for which the current is supplied by the magneto. The simple manner in which the engine is mounted on the cycle part makes possible its being fitted to frames of any design, so that the engine is a suitable power unit for manufacturers who equip cycle parts of their own manufacture with engines which they buy.

An important advantage of the STADION S 1 moped is its low weight, its good riding qualities and its outstanding engine.  It is an ideal machine for travelling to work, shopping, for pleasure and for short outings. It will bring its owners much pleasure and it completes suitably the wide range of the products of the Czechoslovak motor industry.

Taken from Czechoslovak Motor Review
issue 1 1958 for jawamoped.com

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