ORIGINAL: MikeL
ORIGINAL: Espen K
OS #3 is a plug for engine up to .40 size. Bigger engine as the .46 needs OS #8 or equal from other brands.
Sorry, but that's just not true. The A3 is just OS's less expensive plug. Engine displacement isn't a factor.
No that's not true. Now i'll quote for rossi. OS has a simular thing.
R1 - Very hot - From 0.8 to 2 cc
R2 - hot -From 2 to 3.5 cc
R3 - Med - From 3.5 to 6 cc
R4 - Cold - From 6 to 10 cc