Hi this is my first post ,i have just had the same problem with the climber stalling and not starting halfway round a muddy section, I could get the bike going again with a new plug or 20 mins of kicking over ( nearly broke my leg doing this after missing the kick start in temper and pile driving my leg striaght down into tarmac! ) this happen a couple of times and i thought i had bought a dud bike ,until some bright spake told me to send the stator to be checked ,low and behold it needed a re wind , job sorted kicks over 2nd time all the time now.