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James Sports Superswift M25S. 250cc.1963-1966

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Frame numbering 1963 Prefix FM25S - xxx.  1964 Prefix GM25S - xxx etc
Engine Villiers 2T.  (1964 on - 4T) Capacity 250cc.  50mm x 63.5mm
Gears Four speed
Frame Single downtube with swinging-arm rear.
Forks Telescopic
Tyres 1963: 3.25" x 18" front & rear.
1964 on: 2.75" x 19" front.   3.25" x 18" rear
Tyre pressures  
Wheel rims Dunlop WM2 36 hole
Ignition timing 2T:  3/16" btdc.  4T: 5/32" btdc
Points gap 0.012" - 0.015"
Plug gap 0.018" - 0.025"
Plug type Original spec. Lodge HH14
Carburettor 2T: Villiers S22 / 2. 
4T: Villiers S25 / 2  
Jet size  
Needle setting  
Tank capacity 2 gallons approximately.  Use of unleaded fuel will cause no problems
Petroil mixture 20:1 as originally specified. Can be safely reduced to 24:1 with modern oils.
Gearbox capacity Fill to dipstick level.  SAE 30
Chaincase capacity Fill to level plug.
Chains Primary chain:  60 pitches.  Renold 110038
Final drive chain:
Sprockets Engine: (crankshaft) 20 teeth
Gearbox (final drive) 18 teeth " pitch
Brakes 1963: 6" front & 5" rear.   1964 on: 6" front * rear
Taken from Villiers parts list
Main bulb:  6v - 30 / 24w pre focus
Tail lamp: 6v - 3w
Stop light bulb: 6v - 18w
Parking lamp bulb:   6v - 3w
Speedo: 6v - 1.8w
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