Help with disc brakes on bikes?!?

Question

Okay, so the other day I had to take my bike into the shop to get my gears fixed.. To fit it in the car, I had to take the front wheel off. When I got the bike back, I tried to put the wheel back on and found the disc wouldn't fit between the brake pads. I have tried prying them apart with a screwdriver - This made it so the wheel could fit in, but would hardly turn because the pad was rubbing against the disc. Any help would be appreciated as I don't want to pay the bike shop again to fix it!!

Answer 1

Hey Matt,

Sounds like you have Hydraulic brakes.  Sometimes when the wheels are removed the Hydraulic brake lever gets pressed, pushed or even squeezed accidentally, causing the brake caliper pistons to get pumped out.  This makes the brake pads squeeze together and stay that way.  Using a s***w driver does help, but it sometimes ruins the brake pads.  Anyway, since you have the pads opened up remove your wheel and remove your disc brake pads.  Use a closed end wrench or similar and try to open or widen the space between the caliper pistons.  Be careful not to bend or break any of the caliper piston parts.  Once you get the pistons opened up as far as you can, replace the disc brake pads and put the wheel back on.  Then squeeze the brake lever a few times to pump it back up and to recenter the pads.  You might need to recenter the brake caliper by loosening the caliper bolts if it still rubs a little on the brake rotor.  Just loosen the caliper bolts, center the caliper and re-tighten (torque to specs) the caliper bolts.  Anyway, give it a try and let me know if it works.  Good Luck.

Kimber

Answer 2

It's unusual for brakes to go out of adjustment just because you removed the front wheel.  

I'm assuming you have mechanical, not hydraulic brakes. It may be that the brake cable has become slightly dislodged from somewhere along its track to the brake calipers. Check that before making any adjustments to your brakes.

Answer 3

What kind of disc brakes do you have?  Is it avid.  If it is the avids, they have  adjustment k***s on the outer and inner side you can adjust to bring the pads closer or futher from the rotor.  If it is a hayes or if the avids cant be adjusted then disconnect the cable this should fully open the calipers and allow the wheel and rotor to fully seat.  The hayes I have seen only have a adjustment on the inner side to move the pad in or out (5mm allen).  I adjust mine with the cable still disconnected move the actuating arm, to move the outer pad, as close to the rotor without the rotor rubbing.  Holding it at the same time re connect the cable.  Then adjust the inner pad by adjusting the allen s***w.  Just make sure the pads arent rubbing the rotor.  The avids is a lot easier.  Its just a few turns of the adjustment k***s on both inner and outer sides.  For disc brakes though there should be nothing to pry with a screwdriver.