I've had same problem re intermittent starting a quick rock in gear would sort it. Monday it stopping working even when rocked in gear. So this afternoon after work I removed starter motor and stripped it down. Found out it has 2 bushes and one of them had stuck in. Gave it a clean,wd40, removed the shit, put back together and now works a treat.. Just thought I would share it. Maybe worth checking out the bushes before buying a replacement.. Fzs600 02. Cheers