Yes, the rectifier/regulators fail all the time. They are notorious for it. ElectroSport (formerly Electrex) www.electrosport.com makes one (sorry, I don´t have the part number handy). Easy to install. These, compared to OEM, are built much heavier ... the heat sink is far more substantial, and they run much cooler. $100, and worth every penny. My bike never started all that well ... ate batteries ... now, it starts the first time, every time, and the battery is always charged (but I find that I really, really have to keep an eye on the acid level in the battery). By the way, my bike is an ´89 VFR750FK, red, lots-o-mods, and I absolutely love it! Hope this helps.