This system is the perfect choice when building a bike from scratch or when upgrading your weaker charging system. The alternator rotors feature fully encased sets of magnets that have no way of working loose like OEM rotors are known to do.; Kit includes an encapsulated magnetic rotor, precision-wound stator and an 89-99 32A voltage regulator Features a thick .476" center rotor as compared to a .222" center OEM rotor