I have a cargo bike (http://www.christianiabikes.com/en/product/26/) with front wheels having bengal helix 7.5 hydraulic disk brakes.
Inexperienced me, I have taken off the caliper from the rotor on the right side and squeezed the lever. After that I wasn't able to put the rotor back. Then I took apart the caliper (the entire thing, not just the bleeding valve) and leaked some fluid so that I could put the rotor back and took the bike to the bike shop.
They have filled the liquid up but the brakes became uneven. Bike is steering towards left when it is braked. They are saying that they cannot do any better than that since I messed with it and asking me to buy a new brake set.
Is it really true that brakes are ruined? Can I not fix it by completely disposing the fluid and starting over?