Technical B40 specs

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BSA B40 – Wikiwand

BSA 1961 350 Star – B40 Technical Specifications

BSA 1961 350 Star

Engine

SpecificationDetails
Engine Type [SN B40.1318]BSA B40 single-cylinder, OHV
Displacement343 cc
Bore x Stroke70 mm x 90 mm
Compression Ratio8.5:1
Max Power19 hp @ 5,800 rpm
IgnitionMagneto
CarburetorAmal Monobloc 376/376
CoolingAir-cooled

Transmission & Drive

SpecificationDetails
Gearbox4-speed manual
Final DriveChain
ClutchWet multi-plate

Chassis & Suspension

SpecificationDetails
Frame Type [SN: B40.1296]Single cradle steel
Front SuspensionTelescopic forks
Rear SuspensionSwingarm with twin shocks
Front BrakeDrum, 7-inch
Rear BrakeDrum, 7-inch
Wheelbase53 in (approx.)
Ground Clearance6.5 in (approx.)

Fuel & Performance

SpecificationDetails
Fuel Tank Capacity3.5 gallons (16 L)
Top Speed~80 mph (130 km/h)
Fuel TypePetrol
LubricationWet sump

Dimensions & Weight

SpecificationDetails
Dry Weight~330 lbs (150 kg)
Seat Height31 in (79 cm)
Overall Length80 in (203 cm)
Overall Width28 in (71 cm)

Notes / Maintenance Tips

  • Original B40 parts are interchangeable with early Star models.
  • Keep carburetor and ignition properly tuned for optimal performance.
  • Drum brakes require regular adjustment for best stopping power.
BSA B40 Engine BSA B40 Side View