From 1952, Rumi built the SuperSport model of its twin for road racing with two Dell'Orto carburettors mounted vertically above the engine and its own design of bottom-link front forks. The racing Rumis were developed by former FN and Saroléa designer Salmaggi, whose tuned version of the 125cc Super Sport motor produced 8 HP at 7,000 rpm and was good for 72 mph.
Specifications
Engine: Twin cylinder 2-stroke
Bore & stroke: 42 x 45 mm
Compression ratio: 10.5:1
Engine Capacity: 124.68cc
Maximum power: 9 h.p. @ 7.300 rpm
Electrical System: Nassetti magneto, CEV 105 headlight, CEV tail light
Carburettor: Dell'Orto UA 18
Cooling system: Air cooled
Transmission: Gear primary, chain final
Clutch: Cable operated with multiple wet disk
Gearbox: 4-Speed foot-change
Starter: Kick-starter
Throttle: Cable operated
Frame type: Lightweight steel tubing
Front suspension: Telescopic forks
Rear suspension: Plunger
Front Brake: Drum, full-width SLS Ø 140 mm
Rear Brake: Drum Ø 160 mm
Wheelbase: 1,250 mm
Front Tyre: 2.37 x 21 in.
Rear Tyre: 2.50 x 19 in.
Fuel tank capacity: 13 litres (18 litres on request)
Fuel consumption: 3.4 litres per 100 Km
Top speed: 115 km/h
Instrumentation: VDO speedometer 140 Km/h
Weight: 84 kg
Riding position: 1st series with cantilever saddle, second series with leather dual seat
List price at that time: 235.000 lire ex-works
Motor Kampioen magazine: Volume 4, no. 10, 7 February 1953, pp 188-189
Source: Hessink's NL
