have a 250cc hammerhead how many hours or how can you tell when to replace it.

When it breaks...

lol well better info than that. good one jabo
i know on the yamaha with the belts you have to replace after they wear down so much from dirt.
just wondering if anyone has had to do that.

when your tranny is slipping and when it looks like this.............

If it starts to look excessively worn. If it breaks. Or bend it backwards from it's natural position. You will start to see cracks when bent backwards. This is a good indication a belt is shot and ready to break. I have only replaced one belt on my buggy because it was glazed over and making an aweful squeeking sound, but worked good. It's my backup belt. Others have not been so lucky and replace more often. I would guess a lot has to do with how bad you abuse it. If I start to stall on a hill I completly let out of it. No sense in burning up a belt.