Moto RUMI Competition SS52 “Gobbetto”

Called “Gobbetto (Hunchback)” for the unusual “hump” shape of the aluminum carter that protects the magnet mechanism, clearly visible on the left side

• Displacement: 124.68 cm3
• Two-stroke engine with two horizontal cylinders side by side
• Bore and stroke 42×45 mm, compression ratio 10.8:1
• Max speed 8200 rpm, max power 9 HP
• Cylinders in special cast iron and then in aluminium, separate, heads in aluminium
• Carburettor n° 2 Dell’Orto SS 23c/ SS 22c, separate bowl
• Flywheel magneto ignition with two breakers, two firings per revolution, 6 V, 30 W; in Marelli ST261-DAS-D external magnet variant
• Clutch with multiple discs in oil bath
• Four-speed block gearbox always engaged
• Variable rapporti
• Primary transmission by gears, secondary by chain
• Open cradle frame in special light tubes; wheelbase 1265mm
• Fork front suspension with oscillating rods, wheel pushed
• Guided wheel rear suspension with antagonist springs; 2nd series: swingarm
• 36-spoke wheels with aluminum rims: 18″ front, 17″ rear
  2.00 x 18” front ribbed, and 2.50 x 17” treaded rear
• Central expansion front brake with double shoe, double Ø 170 tie-rod
  Ø 170 central expansion rear brake
• Electrical system with Nassetti flywheel-magnet, optional headlight on request for road model
• Instrumentation built-in tachometer in the tank scale 1-10.000
• Suede racing seat guide trim
• 22 liter aluminum tank
• Dry weight 1st series with cast iron cylinders without external magnet 83 kg
• Maximum speed according to the versions from 128 to 136 km/h
• Variable average consumption depending on the trim levels
• List price 470,000 lire
• Color range: ivory with yellow molding on the tank