ESF650 is a brand new rotor that replaces the OEM rotor on all Yamaha XS650 models between 1970 and 1982. The Yamaha OEM rotors on these models are prone to failure due to their age and the bike's vibration and ElectroSport is happy to be able to offer this BRAND NEW replacement rotor. Our ESF650 rotor already has the magnet built in for triggering the electronic ignition on the later models. The earlier XS650 models use points ignition and this ESF650 rotor can be used for that as well. This rotor uses a modern construction method, has a coil that is tight, wound with fabric covering for protection and fixed in place using modern epoxy resins. Fit is like OEM and each rotor has been individually tested before packing. The run-out of the copper brush rings is less than the OEM samples we tested against! ESF650 comes with a full one year warranty.