Modern Vespa

Hi, we have an MP3 that was stored in a barn over the winter. One of the front disc brakes is now stuck on/engaged. Suggestions?

Is this a newer gen MP3 that has ABS? How was the bike stored? Was the bike left exposed to the elements i.e. moisture from cold winter weather? Was the parking brake left on during the winter sleep?

If you are sure the front discs are locked, best strategy is to remove the calipers, loosen the bleeder valves, and manually push the caliper pistons back.

IF the pistons do not retract smoothly, then you are going to need new calipers.

Clean, lube and reassemble everything followed by a complete brake fluid flush.