Best way to get rid of a "squeaky" bike? I'm a college student and my bike is part of my daily commute to class. However, last semester my bike began squeaking and the squeak got louder and louder as time went on. I tried spraying some WD-40 on the crank-shaft, but this was only a temporary fix. Is there a better way to get rid of the squeaking sound than spraying WD-40 every couple of days?
It may be as simple as retightening your cranks onto the bottom bracket axle.

It fixed my everlasting squeak. (Not: square tapered bottom bracket axle)

I took the hint that the creak was strongest when bearing down on the left pedal.