Model B 125

  • B 125

The Lambretta model B was an update to the Model A 125 with integrated suspension in the engine and larger 8 inch wheels.

Technical Specification

Model B 125
AmountProduced 35014
Production Dates November 1948 – January 1950
Frame Prefix No Prefix
Engine Prefix Tipo 3 (First 40) then Tipo B
Frame Starting Number 00001
Engine Starting Number 00001
Homologation Unknown at this time
Engine 123cc, two stroke, 52x58mm
Power and Rate 4.3hp at 4200-4500rpm
Compression Ratio 1:6
Head and Cylinder Aluminium and cast iron
Engine Cooling Air
Ignition Filso or Marelli magneto
Spark Advance 26' – 28' 33 – 35 mm on the circumference of the flywheel
Point Setting Flywheel .40-.50 mm
Carburetor dell'orto MA16
Choke 16mm
Slide 55
Needle C9
Atomiser 260
Main Jet 65
Pilot Jet 45
Starter N/A
Float 7.5 grams
Starter Pedal
Crankcase oil Mobil Oil A 180 grams
Transmission Oil Special Grease 150 grams
Oil / Gas Mix 5%
Clutch Multiple discs in oil bath
Gears 3 speed with hand shifter
Primary Transmission Gear
Secondary Transmission Shaft and Gear
Frame 1250mm stamped metal
Front Suspension movable paraellogram with helical springs
Rear Suspension Joint attached to motor with hydraulic shock absorber
Wheels Dismountable wheels
Tires 3.50 x 8 pirelli
Tire Presure Front .7-8 ATM, rear 1.75 ATM
Brakes Drum
Dry Weight 68kg
Km Per Gallon 1lt per 50km
Fuel Capacity 7lt plus .8lt reserve
Max Speed 65-70kmh
Initial Price 135,000 Italian Lira
Electrical System 6 volt
Sparkplug Bosch 225 short thread
wheel Base
Maximum Length
Ground Clearance
Maximum Seat Hight
Minimum Turning Radius
Colour Metalic Red 8023
Metalic Blue 8024
Metalic Green 8025
Metalic Bronze 8053
Engine Colour Fiat 690