A.J.S. 16, Instruction Book

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Engine overheats may be due to :
Lack of proper lubrication. (Quality or quantity of oil.)
Faulty sparking plugs.
Air control to carburetter out of order.
Punctured carburetter float.
Engine carbonised.
Weak valve springs.
Pitted valve seats.
Worn piston rings.
Ignition setting incorrect.
Automatic timing control faulty.
Engine stops suddenly may be due to :
Stuck up valve.
No petrol in tank, or choked petrol supply.
Choked main jet.
Oiled up, or fouled, sparking plugs.
Water on high-tension pick-up, or sparking plugs.
Water in float chamber.
Vent hole in petrol tank filler cap choked.
Loose coil connections.
EXCESSIVE OIL C O N S U M P T I O N
Excessive oil consumption may be due to:
Stoppage, or partial stoppage, in the pipe returning oil from the engine to the oil tank.
Badly worn, or stuck up, piston rings. (Causing high pressure in the crankcase.)
Air leak in dry sump oiling system.
Worn inlet valve stems.
Improper crankcase release valve action.
EXCESSIVE PETROL C O N S U M P T I O N
Excessive petrol consumption may be due to:
Leaks in the petrol feed system. (Damaged fibre washers, loose union nuts on piping,
defective float needle action.)
Incorrect ignition setting. (Ignition not advanced sufficiently.)
Defective engine valve action.
Incorrect use of air control lever.
Moving parts of carburetter badly worn. (Only possible after very considerable mileage.)
Bad air leak at carburetter junction, or inlet manifold joint.
STEERING UNSATISFACTORY
Incorrect steering head adjustment (too tight or excessively slack).
Pitted steering head ball races resulting from loose adjustment.
Wheels out of alignment.
Front and/or rear tyre tread not correctly manipulated to run true with wheel (causes
handlebar oscillation at low road speed).
Damaged front fork main tubes resulting from impact.
A B N O R M A L TYRE WEAR
Abnormal tyre wear may be due to:
Incorrect tyre pressure.
Wheels not in alignment.
Harsh driving methods. (Misuse of acceleration and braking).
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