James Motorcycles Information Website

James Superswift M25. 250cc. 1962-1963

Homepage Superswifts Superswift M25  Specification
Identification Specification Sheet Paint & Chrome Transfers (Decals) Manuals
Related topics

James motorcycles.
A brief history.

British Two Stroke Club.
How to join.

Where can I buy....?

Manuals etc.


Other stuff


Frame numbering 1962 Prefix EM25 - xxx.  1963 Prefix FM25 - xxx.
Engine Villiers 2T. Capacity 250cc.  50mm x 63.5mm
Gears Four speed
Frame Composite frame with front top & down tube, fabricated central section and pressed rear mudguard.
Forks Telescopic. 1962 - Mk.1.   1963 - Mk2.
Tyres 3.25" x 18"
Tyre pressures  
Wheel rims Dunlop WM2 36 hole
Ignition timing 3/16" before top dead centre.
Points gap 0/012" - 0.015"
Plug gap 0.018" - 0.025"
Plug type Original spec. Lodge HH 14
Carburettor Villiers S22 / 2
Jet size 170cc, 180cc or 190cc
Needle No.3
Throttle No. 3 cutaway
Pilot jet 35cc
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 The gearbox has a dipstick. The correct level of oil is then assured.  Check it regularly.  Castrol "XL"  SAE 30
Chaincase capacity Fill to level plug.  Castrolite SAE 20
Chains Primary chain:  60 pitches.  (Renold 110038)
Final drive chain:  " x 0.335" x 0.305" wide. 20 teeth (Depends on final gearing).
Sprockets Engine: (crankshaft) 20 teeth ( I think) x ⅜" pitch.
Gearbox (final drive)  " pitch. No. of teeth depends on gearing.
Brakes 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
JamesWisdom@hotmail.com   Simply Wizard