WHEELS Mfg Ball Bearings

Grade 25 refers to the precision of the bearing's sphericity and diameter tolerance. It is a high industry standard that ensures the balls are nearly perfectly round, which minimizes friction and wear within your hubs, headsets, or bottom brackets.

While these are standard-sized bearings, compatibility depends entirely on the specific diameter required by your component. You must verify that your hub or headset specifically calls for 5.56mm (7/32 inch) bearings before installing them.

These are loose ball bearings designed specifically for cup-and-cone style systems. They are not compatible with cartridge bearing units, which are sealed, self-contained assemblies.

Yes, you should always use a high-quality bicycle-specific waterproof grease when installing loose ball bearings. This helps hold the bearings in place during assembly and provides a protective barrier against moisture and contamination.

It is strongly recommended to replace the entire set of bearings at once. Mixing new, perfectly round bearings with worn, pitted ones will cause uneven wear and compromise the smoothness of the component.