To provide a starter capable of starting an engine by small tensile force by utilizing a buffer spring and reducing stress applied to a spring part simultaneously to realize long durability and high reliability.

This energy accumulation starter assembly is provided with a pulley 20, a hub 40, and a buffer part 30, the buffer part connects the pulley and the hub elastically and mutually and accumulates and transmits energy between the pulley and the hub, and both end parts of the buffer part can be exchanged so as to store any of end parts of the buffer part in either of the hub and the pulley.