Hi there, I have a KTM exc 250 2 strokes that I bought last years and since then it always been make the same problem. I put a bran new spark plug, the bike start first crank, I warm it up. ride for an hour or more if I want. then I come back to my place and shut it off. next day or anytime later, I restart the bike without any problem, then I warm it up a little without giving too much gas, AND, as soon as I give a little too much trottle it goes dead. So I check the plug, It doesn't look too rich or anything, I brush it with sand paper and try to make it spark again and : nothing ! the spark plug just died like this. I've tried what ever is possible the make the plug spark but it won't make any other spark after that. If I put a new one in the bike, the game restart. what could it be? missing voltage regulator and it give too much amp or volt to the coil and it make the spark plug weak after one ride? its like if the wire inside the spark plug get weak after extreme condition and the wire after the ride get cut by anything too extreme and top working. it would be the reason why it blow any spark plug after one run. spark plug I try: BR8ES, B8ES. gas ratio : 40:1 Klotz oil. premium gas main jet : I had a 185, I though it was the too rich reason and put 173, but still doing the same problem. bike is stock. any idea?