Dave102429
11-15-2004, 11:07 AM
On a 2002 400EX, there's a 5K resistor inside the spark plug cap/boot behind the terminal that the end of the spark plug snaps in. Back when I had my XR250, the hot trick was to replace the resistor with a piece of cooper welding rod of the same size as the resistor. My XR250 ran pretty good and I never had a problem with it. Has anyone tried this trick on a 400EX? What's the purpose of the resistor? Thanks.