Allround · 1957
Commodore 250
Technical Overview
1957 James Commodore 250 Technical Analysis & Specification Breakdown
At the heart of the 1957 James Commodore 250 allround motorcycle, James pairs a 249 cc (15.2 cu in) air-cooled single cylinder, two-stroke architecture with road-focused gearing. Internal engine geometry specifies a bore and stroke of 66.0 x 73.0 mm (2.6 x 2.9 inches).
Within MotoLibrary's James archive, this model family spans 6 indexed model years from 1957 to 1962, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Engine
Displacement 249.0 ccm (15.19 cubic inches)
Engine Type Single cylinder, two-stroke
Engine Details Single cylinder, two-stroke
Bore x Stroke 66.0 x 73.0 mm (2.6 x 2.9 inches)
Fuel System Carburettor. Amal
Cooling Air
Transmission
Gearbox 4-speed
Final Drive Chain (final drive)
Chassis
Front Suspension Hydraulic telescopic
Rear Suspension Swingarm-two shocks
Wheels & Brakes
Front Tyre 3.25-18
Rear Tyre 3.25-18
Front Brakes Expanding brake (drum brake)
Rear Brakes Expanding brake (drum brake)
Wheels Spoked
More from James
Buying Checklist
Before You Compare This Bike
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
Rider Profile
Who Is This Bike For?
🌍
Best For
All-Round & Adventure
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