So.... return a bunch of "new" plugs with crushed washers? Guess I better check my new plugs when I buy them.There are some tricks to improving performance on the plugs:
Cutting the lateral electrode back so it's tip is at the center of the center electrode gives better spark..more even and stronger
and/or marking where the opening faces on the plug's electrodes on the outside of the plug so you can see it when installed then "find" a set of plugs that when installed and tighten properly the opening faces the point where the gas enters the cylinder. ON Goldwings straight up at the center... IE you buy a lot of plugs and return most. Old racing mechanic's trick.