I subbed a standard 55/60 watt round halogen from a car on my 550 to replace the stock 40 watt one. Charging system wouldn't carry it all the way, started blowing main fuse, but after dropping the running light portion of front turns and using LED brakelight to conserve power, head light is much more powerful now. No more blown fuses either. Plug was identical on mine, just unplug old and plug in new.