to check your brakes you need to pull the front wheel and look and the pads. there is a slot in the caliper. if you look into the slot you should be able to see the pads on either side of the rotor. the pads should be visiable and there should be roughly 1/4" min. when looking dont just look at the metal plate there are pads attached to the plate. also dont spray wd-40 on them. they make brake part cleaner which evap. quickly. when brakes squeal that is usually the way of letting you know they need changed. brake pads come with a squealer that drags on the rotor when they need changed