Hi all I have a wr 400 f 1999 model. I have rebuilt this bike from the death and I am satruggeling with one problem. The bike runs 100s bt sometimes the bike just dies and there is very little spark, then the next week the spark is fine. Lately there is no spark and then spark again. At the moment there is no spark, the stator coil has been redone and the problem persists. Do you know what the problem could be? Please need you help thanks.