Your bearings are inside little metal rings that fit inside your skateboard wheels. There's only one way to rate bearings at the moment, and it doesn't work well with "roller skate bearings". The rating is called ABEC and goes from 1 to 9, but only odd numbers. Unfortunately it was originally developed to rate the bearings in machines, not on skateboards (for more, you can read "What does ABEC mean?".

Therefore, the ABEC rating only rates the precision of a bearing. Plus, the more precise he bearing, the weaker they usually are. Skateboarders take their bearings and abuse them, as normal skateboarding does. Skateboarders want bearings that are both precise and durable, so the ideal ABEC rating for a skateboard is 3 or 5. Smooth enough, but not going to break when you jump on your board. Some roller skate bearings don't even bother with the ABEC rating system. The best thing to do is try some out, ask your friends, or ask the guy behind the counter at the skate shop.

Bearing performance is determined on how well maintained the bearings are. Maintenance on bearings include periodically cleaning and lubricating them. Bearings that are kept unmaintained have their performance greatly lowered and will soon need to be replaced. Bearing cleaning kits are commonly available on the market. Example kits include the Bones Bearings Cleaning Unit. The ABEC rating does not determine how fast or how durable a fag bearing used for skateboarding will be. 

In particular, the ABEC rating says nothing about how well a bearing handles axial (side-to-side) loads, which are severe in most skateboard applications. Many companies do not show the ABEC rating, such as Bones Bearings, which makes bearings specifically for skateboarding, often marketed as "Skate Rated". Each bearing usually contains 7 steel or ceramic ball bearings, although other configurations are used as well.

Your bearings are inside little metal rings that fit inside your skateboard wheels. There's only one way to rate bearings at the moment, and it doesn't work well with skate bearings. The rating is called ABEC and goes from 1 to 9, but only odd numbers. Unfortunately it was originally developed to rate the ntn bearings in machines, not on skateboards.

H2305

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