All of what nick said made good sense, however..... not many of them
accounted for air in the brake lines. Excessive lever travel or pumping to
get pressure could be the result of the pistons being sucked back into the
caliper or warped discs pushing the pistons back into the caliper. Motorcycle
master cylinders do not move the volume of fluid that a car MC moves so if
the pads are not very close to the disc, it will require pumping to get a
solid feel. The reason for mentioning this is to help people understand the
difference between the two. If you pump the brake and it gets firm, you do
not have air in the line, look for something that is causing the pads to move
away from the disc. If you pump the brakes and they remain spongy, then you
have air in the lines, which will be evident upon bleeding. These are two
different problems with two different solutions. They could occur at the same
time, but still require two separate solutions.
RSRBOB
