i have a magnum .52 2 stroke running on 10% and thunderbolt r/c long idle bar plugs. i'm using the 12.25x3.75 prop (which is probably only about an 11 now b/c i've dinked it a couple of times on landings).

lately, my plugs keep on burning out. i'd have about 2 flights on them before they need to be replaced, sometimes, just one flight!

i've been through about 5 plugs already in the past 2 weeks! i made sure i wasnt running too lean and have opened up the needle valve even more and am almost certain i'm running rich now but the problem continues.

does anyone have any ideas or suggestions? maybe i just got unlucky with a bad batch of plugs from thunderbolt?

thanx,
brian