|Exploded View of a Bearing|
Number of Balls
ABEC vs Skate RatedI've had some people pick up a pack of bearings, ask what ABEC rating they were, then when I told them they weren't ABEC rated but rather were "Skate Rated," they put them down and wanted to purchase only ABEC rated bearings. This is a tell tale sign of either a new skater, or someone who hasn't done their research. ABEC, or Annular Bearing Engineers Committee rates dimensions, tolerances, geometry, and noise standards for bearings in an attempt to aid industrial bearing manufacturers and users in the production, comparison and selection of bearings for general applications. Meaning this is a generic overview of how well a bearing works for a wide variety of uses. ABEC ratings are noted as odd numbers from 1 to 9, the higher the number, the tighter the tolerances.
For instance, bearings used in machinery such as high speed routers would need to be precise when turning at 30,000 revolutions per minute (RPM) and would usually have an ABEC rating of a 7 or 9. To put this in perspective, you would be traveling about 190 MPH if your wheels rotated at 30,000 RPM. If you are going to do some downhill racing, then you may want to look at some ABEC 7 or 9 rated bearings, but for most Roller Derby activities Skate Rated bearings are what you want to look for.
When you are skating, you are moving and jumping around a lot, which causes bearings to be jostled, impacted, and pressured in ways that they wouldn't if they were just turning in a machine. Skate Rated bearings take into account things like side loading, impact resistance, materials selection and grade, appropriateness of lubrication, ball retainer type, grade of ball, the clearance between the balls and the races, installation requirements, and the need for maintenance and cleaning. You can read more of the details of Skate Rated vs. ABEC at the Bones Bearing website.
Breaking InGRN MNSTR Moto Deluxe bearings, which come pre-spun and ready to go out of the package. They also come in a cool metal container that prevents any of the lube from leaching into the packaging, unlike most other bearing packages.
If you take the bearings out of the package for the first time and there are any hitches or they won't roll at all, contact the manufacturer because this is likely a defect. Now, I don't mean if they are slow, because as previously said, they need to be broken in to spin quickly. Also, if you have a bearing that falls apart after only skating on it for a little while, this is a defect that the manufacturer will usually take care of.