Guys, I'm new to this board but would really appreciate any of your insights. I have a 2002 WR426 with grey wire mod, std. timing, full throttle mod and lid removed. I experience severe backfiring and plug fouling since making the gray wire mod. I've made no carb adjustments. The bike runs better with the stock (no baffles) pipe than with my IDS2 - I've tried as few as four and as many as twelve rings in that pipe. The plug is BLACK and sooty even after only a short ride. The timing has never been played with, but it bikefires so badly I was thinking that could be the cause. I'm no kind of mechanic, but is all of this a indication of too lean or too rich a mixture. By the way, even with the backfiring, this bike is still bad FAST. I will really be thankfull for any insight.