Spark Plug NGK B6ES
AMC Engines
AJS 1950-1964 All models (alloy heads) exept racer
Ariel Square 4 MkII Alloy, OHV models alloy head except FH, HS
BSA B32GS, B40, B34 Alloy Head, C10L, C15, C15T, M21 Alloy Head
Matchless 1950-1964 all models, alloy head except scramblers and racers
Norton Model 16H 500cc SV, Big Four 596cc SV, ES2, 88, 7, 99, Alloy, 19R, 19S, 50, 77, 500T
Royal Enfield 350cc Bullet, 500cc Bullet 3/4" reach, Meteor Minor Sports, From Eng. no. 7028 onwards, 700cc constellation
Rudge Special & Ulster 14mm Alloy
Sunbeam 1946 onwards S7 & S8 Twins
Triumph T140, TR65
Velocette KSS 350 MkII, MAC 350cc Alloy, Viceroy
Vincent Black Shadow, Rapide, Comet, Meteor, Lightning, Prince, Knight, Victor