[Alex]

Hi all,

I would be interested in any experience you have regarding spark plugs for the 500 ohv engine.
Does anyone has experience with using other than the original spark plugs, like for example NGK B#ES (M14) or what I would prefer in order to bring the center electrode closer to the chamber the NGK D#ES (M12).

So far I found out that in general NGK B#ES (Champ N#) seems to be the most common used for englisch pre war bikes.
Using the B#ES type and due to the nature of the insert the center electrode would still end up slightly offset from the combustion chamber (around 2-3mm from the end of the thread end), with a D#ES I could make the thread insert in a way to not modify the cylinder head and arrive end/end plug to thread.

Curious on your thoughts.

BR
Alex