How do you know when you need a new clutch in a harley Davidson?

The clutch encompasses the drum, the hub, the bearings, the spring(s), the pressure plate, the friction plates and the steel plates. There is rarely any need to replace more than one of these items (or sets of items, such as plates).

If the drum, hub or pressure plate show excessive wear or physical damage, it should be replaced. If the friction plates are worn beyond service limits, they should be replaced. If the steel plates are warped from excessive slippage, they should be replaced. If either bearing turns roughly it should be replaced.