1952-1953 Adler M250S

Specifications

Engine:
Air cooled two-stroke twin, 247cc, B/S 54x54mm
Compression ratio 5.75:1
Amal 20E1B carburettor (1952)
Bing 1/22 (1953)
multi-plate clutch in oil bath
two ignition coils

Power: 18 HP @ 5600 rpm

Lubrication: 25:1 petroil mixture.

Fuel consumption: 3.56 litres/100k @ 80 km/h

Gearbox

4 speed with neutral indicator
Oil capacity: 1.2 litres
Gearshift lever on left side of engine
Shift pattern: 4 up - neutral, 1st, 2nd, 3rd, 4th.
1st gear = 2.80:1
2nd gear = 1.53:1
3rd gear = 1.11:1
4th gear = 0.81:1
primary drive = 3.44:1
final drive = 2.0:1 (solo), 2.25:1 (sidecar)
NB: All MB/MBS models have same gearbox and gear ratios.

Max speed: 125 km/h

Weight: 135 kg (1952)

Weight: 145 kg (1953)

Wheels: 1.85 x 16" steel rims, 36 spokes.

Brakes: 180mm x 30mm.

Tyres: 3.25x 16 front and rear.

Maximum all-up weight without sidecar: 295 kg; with sidecar: 420 kg

Frame: double cradle steel tube with sidecar attachment points.

Fuel tank: rubber mounted 12 litre with 3 litre reserve.

Front suspension: leading link with integral damping.

Rear suspension: hydraulic spring dampers.

Electrical system: 6 volt 90 watt flywheel magneto.

Steering lock.

Lockable toolbox.

Adjustable steering damper.

Enclosed rear chain.

Folding rear guard.

Upswept dual exhaust. .