07-17-2021, 03:46 AM
Did you wash it with a hose and water? It's possible a piston rusted slightly and is now locked in position. I haven't heard of this happening so quickly to a bike in storage though. I suggest that you do NOT apply excess pressure to the lever to try to unlock it though. Disconnect the hose from the caliper and use compressed air to try and free up the pistons.
