Hydraulic Brakes When Transporting A Bike
Hydraulic brakes work by two pistons, one on either side of the caliper, pushing the brake pads towards each other until contact is made with the disc rotor.
The first photo shows the brake pads touching each other inside the caliper. Between the right brake pad and the caliper you can also see the piston has been pushed too far out of the caliper.
This is very common when bikes are transported, especially in the back of cars.
When the wheel is taken out of the frame, if the brake levers are accidentally pressed together the pistons will extend and push the brake pads towards each other, as you would expect. Not having the disc rotor between the brake pads means the pistons will keep extending until the brake pads touch. The problem you will now have is the disc rotor will not fit between the brake pads.
By removing the brake pads and pushing the pistons back into the caliper normally works. I’d recommend a wide plastic tyre lever to do this. If this doesn’t fix the problem then give us a call and we can carry out the repair for you.
I always say that prevention is better than cure and this problem can be easily avoided by placing something between the pads when the wheel is removed.
Personally I use a piece of cardboard wrapped in Gaffer tape, shown in the bottom photo.
Not only are these durable and cost a few pence to make, but you can keep adding layers of Gaffer tape until you reach the required thickness. I tend to make mine slightly thicker than the disc rotor so they are a nice snug fit between the pads so they don’t fall out in transportation.