It's been good as gold since, squirt some contact cleaner down the key hole and turn it on/off a few times. It could also be the killswitch possibly. When it fails to start try doing each switch one at a time, but try to start it after each one... that way you'll find out exactly what it is that's stopping it 
In other news, my cam chain has finally adjusted itself and stopped rattling too :woot
In other news, my cam chain has finally adjusted itself and stopped rattling too :woot