Lambretta A/B/C/D/E/F/J/Lui
LAMBRETTA
B 125 ccm 2T AC '48-'50

LAMBRETTA B 125 cc 2T AC '48-'50

Photo from LAMBRETTA B 125 cc 2T AC '48-'50 | LAMBRETTA

Overview Lambretta 125 B

In view of the success of the Lambretta 125 A innocenti decided to bring out an improved model in November 1948. This model B was not only a further development, but also the first model to be imported to Germany by the Winter company in Hamburg. In a way, the B model represented the logical development of the A series.
The innovations of the B model were not limited to aesthetic aspects, but also included significant technical improvements. One major advance was the introduction of elastic rear suspension which, in combination with the two front springs, provided a very balanced ride. The enlargement of the tyres to 8 inches increased stability and the adapted seating position improved comfort.
An important change was the relocation of the gearstick from the footboard to the handlebars, which was now operated via the patented Teleflex cable. The twist shifter, which was retained on all Lambrettas, was another innovation. The remaining cables were routed on the outside of the frame, which made replacement much easier. The fuel tank was enlarged to reduce the frequency of refuelling stops.

Lambretta 125 B model history

Similar to the Model A, the Model B also underwent a number of changes during its production period. The brakes were improved, particularly on the later models. Instead of the brake pads being permanently embedded in the brake drum, they were now mounted on the brake blocks, which made it much easier to replace the brake pads.
Production of the Model B was discontinued in January 1950 after 35,015 units had been manufactured. All B models were delivered in metallic paintwork.

125 B - 1st series (up to frame number ~ 20000)

In this first series of the 125 B model, the brake pedal was designed to be operated with the heel and the clutch cable ran inside. The light switch was located on the lamp housing, but was moved to the right-hand side of the handlebars on the last 2,000 vehicles of this version. Cylindrical rubbers were inserted between the tank and glove compartment, and the kick starter had a vertical bolt.

125 B - 2nd series

In the second series of the model, the brake pedal was moved to the front and could be operated in the conventional manner. The clutch cable now ran outside, the cylindrical rubbers between the tank and glove compartment were removed and the kick starter was fitted with a horizontal split pin.

125 B - 3rd series

In the third series of the 125 B model, the diameter of the rear suspension mount was enlarged and secured with screws. In addition, the two thick rubber buffers under the railing of the glove compartment were removed.

Used Lambretta 125 B market situation

Where do you look for this vehicle?

The colours of the Lambretta 125 B

Colour

Colour name

Colour code

Colour info

azzurro-metalizzato-8024

Azzurro Metalizzato

8024

bronzo-metalizzato-8053

Bronzo Metalizzato

8053

rosso-metalizzato-8023

Rosso Metalizzato

8023

verde-metalizzato-8025

Verde Metalizzato

8025

General Information

  • Producer LAMBRETTA
  • Model B
  • Displacement 125 ccm
  • Cycles and cooling 2T / AC
  • Year of construction '48-'50
  • Chassis number (from/to) 00001-&gt
  • Built quantity 35014
  • Dimension LAMBRETTA
  • Vehicle type Lambretta A/B/C/D/E/F/J/Lui

Years of production & chassis numbers

  • Year of construction:

Technical data

  • Chassis type: open tubular steel frame
  • Length: 1680 mm
  • Width: 650 mm
  • Height: 900 mm
  • Wheelbase: 1250 mm
  • Ground clearance: 120 mm
  • Weight (empty): 68 kg
  • Performance (PS): 4.2 PS
  • Performance (kW): 3.09 kW
  • at rpm: 4400
  • Top speed: 68 km/h
  • Engine type: 2-stroke internal combustion engine
  • Engine manufacturer: Innocenti
  • Engine number: TIPO B (erste 30-40 Exemplare: TIPO 3)
  • position of engine number: right-hand side Engine in the area of the switching scale

Engine - cylinders, clutch & exhaust

  • Displacement: 123 ccm
  • Bore: 52 mm
  • Stroke: 58 mm
  • Number of cylinders: 1
  • Transfer ports: 2
  • Type of cooling: Air
  • Compression: 6:1
  • Starter: Kickstarter
  • Clutch: Multi-disc clutch in oil bath on the Crankshaft
  • Clutch type: Ø 85mm, 3 Clutch Friction Plates, 6 Springs

Engine - Carburetor

  • Mixture preparation: Carburetor
  • Type of carburetor: Dell'Orto MA 16
  • Main jet: 68

Engine - Transmission

  • Type of gearbox: Manual gearstick
  • Number of gears: 3
  • Gear rotation: 1st gear: (9,25)
  • Gear rotation: 2nd gear: (6,38)
  • Transmission: 3rd gear: (4,35)

Engine - Ignition

  • Ignition type: Interruptor ignition
  • Ignition timing: 26 °
  • Battery voltage: 6 V
  • Charging power (ignition): 30 W
  • Spark plug type: NGK B8HS / Bosch W4AC
  • Spark plug thread: short thread

Chassis - tires and rims

  • Front tyre(s): 3.50x8
  • Front rim(s): 2.50x8
  • Rear tyre(s): 3.50x8
  • Rear rim(s): 2.50x8
  • Front tyre pressure: 1,0
  • Rear tyre pressure: 1,75 - 2,5

Chassis - Brakes

  • Brake system: Drum Brake
  • Front brake: Ø inside 100 mm
  • Front brake operation: mechanical with Cable
  • Rear brake: Ø inside 140 mm
  • Rear brake operation: mechanical with Cable

Chassis - steering column & swing arm

  • Front suspension: Springs without Shock Absorber
  • Rear suspension: Springs without Shock Absorber

Electronics

  • Alternator: 6V
  • Headlights: 6V 25/25W BA20d
  • Taillights: 6V 5W

Operating materials

  • Fuel tank capacity: 6.8 l
  • Included reserve: 0.8 l
  • Mixing ratio: 1:50
  • Range (approx.): 277 km
  • Gearbox oil: SAE 30
  • Amount of gearbox oil: 0.5 l
  • Fuel consumption: 2.45 l/100km

Explosion for this vehicle type

Spare parts exploded views

Spare parts exploded views

Our online exploded views for scooters make it much easier for you to find the right part. Each item is assigned exactly to the corresponding vehicle, with year of manufacture and chassis number. From our Expo lists, you can navigate directly to the spare parts, where a photo and a description are then available for almost every part. Conversely, you can also navigate from the item detail to the corresponding exploded view.

Notepad for this model

Our product recommendations for this model

×