Wheels Manufacturing Essential Kit – Bearing Extractor. These extractors remove sealed bearings with inside diameters from 15 17 20 and 25mm. Bearing extractors grip the inside race of a sealed bearing allowing the bearing to be tapped out of the hub shell or frame component. Insert the extractor into the bearing tighten one side with a matching wrench and the collet expands to grip the inside of the bearing. Tap the extractor & bearing out together with a punch and hammer.