Reply To: Spark plug

[Mumbles]

NGK B6S is equivalent to the old J6J which has been replaced by the J6C. I don’t think NGK makes anything hotter in that style and if they did, it would be a B4S. Champion J8C would be the next hotter plug up from the J6C.

If your motor needs hotter plugs, you should try and find out why. If it is trolled a lot or the carb is adjusted too rich, then a hotter plug will be required. Running way too hot of a plug can cause pistons to melt but you should be OK with the J8C’s.