Belt contacts the upper bolt boss on the front pulley cover. That's the squeak. Only happens when the suspension compresses down.
I would advise against anything sprayed on the belt as it will attract and hold dust/dirt... the enemy of the belt and pulleys.
2006 Victory Kingpin
110 Cubic Inches -- Balanced S&S crank/rods, Lloydz iron liner big bore, 11:1 Wiseco pistons, massaged
stock heads, stock throttle bodies/injectors/intakes, S&S .495 cams/springs/retainers, Torque Tubes
airbox, RPW Thor pipe, Lloydz ECU, PC-III, Rivera Pro clutch spring, 31 tooth pulley w/Buell belt