Here's a set of plugs, from a standard 1150GS, original air filter, cat , standard can, no cat code mods -
and a set from an 1150GS with a Y piece, remus, K&N, cat code mod -
Both sets of plugs are NGK, standard bike set done 12K miles, other set done 11K miles -
Can you tell which is from what bike ?

and a set from an 1150GS with a Y piece, remus, K&N, cat code mod -
Both sets of plugs are NGK, standard bike set done 12K miles, other set done 11K miles -
Can you tell which is from what bike ?


