On my '99 21V Riders sometimes it just klicks instead of turning over. Thought it was starter going bad so I got it rebuilt. Didn't fix the problem. When it turns over it starts really good so I don't think it is a battery. Maybe a nutral switch? What would you guys check next? Are there any soleniods for the starter other than the one on it? Any help would be great. It's a sporadic problem that is driving me nuts.