Champion. 18mm x 1,5 diameter at thread. =Sports engines = Bosh M7AC and M5AC.
Height without Thread: 60mm.
Early H,J,K,WM20/21 Bsa.
16H Norton. Big 4
All Norton SV Mod.
Ariel OHV Mod. which use 18 mm spark plugs
Please Note:
mid war changing to 14 mm
M20 and 16H owners, please check the size of your spark plug, as it can be 14 mm or 18 mm.
If 14 mm order spark plug L86C
Compareable spark plugs
Bosch alt M 240 T1
Bosch neu M4AC
NGK A-7
AJS OHV Models 18mm
Ariel OHV Models 18mm
Matchless OHV Models 18mm
Norton All SV 18mm
Rudge 18mm
Sunbeam All 18mm
Triumph OHV Models 18mm
Villiers Engines 98cc 35PD, 197cc MK 5E
Vincent 18mm