well, the truth is....NGK is the easiest plug to foul, period. champion is one of the hardest. the reason is, is that under a microscope the NGK has very porous ceramic around the electrode, whereas the chapion has much less porous ceramic...othe rplugs im not sure about but we have literature for ASE stuff in our automotive library at my college....i always wondered why my dad didnt like them when he raced sled back in the day, so i researched it....i use br8eg's in my R and i havent had any problems, but NGK's are not going to be reliable if your bike isnt very close to being in tune...
1985 Honda ATC250R drag trike with s/t kit and full drag CR hybrid motor and drag chassis...
1986 Honda ATC250R daily rider fully modded engine, +4 swinger,etc...
1997 Polaris Storm 800 triple, boyesen reeds, dg individual silencers, 240 studs, 123mph on radar...