I assume your rear tire is what's skidding? If you can grab the brake level hard enough to make your front tire skid, or almost skid, on dry pavement, the brakes aren't your problem. (And I wouldn't recommend actually locking up the front, that's a good way to fall.) Rider skill is the number one factor in stopping safely. This is just as true on a motorcycle as it is on a bicycle. Practice pushing the limits in a safe place.