https://www.ebay.com/itm/04-08-Buell-Lightning-Xb12s-Buell-Rectifier-Voltage-Regulator/324000764400?hash=item4b6ff351f0:g:UQgAAOSwAeBdryR4
Type: Posts; User: Silverrider
https://www.ebay.com/itm/04-08-Buell-Lightning-Xb12s-Buell-Rectifier-Voltage-Regulator/324000764400?hash=item4b6ff351f0:g:UQgAAOSwAeBdryR4
Most likely your VR is on the the way out, bulbs are cheap replace it before it fries relays and ECM. JMO