VMB Vespa ET3
Frame VMB1T · 1976–1990 · Small frame
Engine
TypeSingle cylinder, air cooled 2-stroke
Barrel3 transfer ports
InductionDisc valve
Bore × stroke55 mm × 51 mm
Displacement121.1 cc
Compression ratio9.25 : 1
Power7 bhp @ 6,000 rpm
Lubrication2% (pre-mix)
Transmission
Type4 speed constant mesh
1st gear14.74 : 1
2nd gear9.80 : 1
3rd gear7.06 : 1
4th gear5.31 : 1
ClutchWet, multiplate
Carburetor
CarburetorDell'Orto SHB 19/19
Main jet76
Slow-running jet45
Starter jet60
Throttle valveNo 2
Ignition & Electrical
IgnitionElectronic
Timing20° BTDC
Breaker gap0.3–0.5 mm
System6 volt
Wheels & Tires
Wheels10″
Wheel hubsCast w/cooling fins
Tires3.00 × 10
Performance
Top speed56 mph