Bearing Purchasing Guide

Posted by Thomas Shaw on October 20th, 2019

This guide covers the fundamental aspects that influence a bearing’s cost and functionality so that you'll be able to make an informed choice when getting your subsequent set. Get additional info about NTN 7320BDBT bearings

Subjects covered on this web page include:

Size
Rating
Materials
Ball Count
Serviceable vs Sealed

Size
The vast majority of bearings used in skating applications are sized for 8mm axles; they are also known as common 608 bearings. 7mm (627) bearings are somewhat uncommon by comparison, though other sizes like Micro (688) are only rarely seen. As the only true restriction in relation to bearings, we recommend acquiring the size that your axles and wheels are made to utilize.

Components
Bearings are most efficient when friction is at its lowest, so components play a pivotal part in overall performance. Several bearings are constructed from steel alloys which are tough and affordable. Maintain an eye out for elements or coatings created from bronze, titanium, and specially ceramic - these will enhance a bearing’s resilience, durability, and functionality. Ceramic bearings are widely regarded because the most effective that money can buy.

Rating
Quite a few makers seek out an ABEC rating that scores bearings on a scale of 1-9. Higher ABEC scores indicate a much more precisely created bearing, nevertheless, the system was created for industrial applications, not skating. Consequently, a number of companies forgo ABEC ratings on their skate bearings and go for “skate rated” labels that signifies that the bearing was tested and authorized for skating.

Number of Balls
Skate bearings traditionally have seven balls that provide a great balance of acceleration, best speed, roll, and durability. Six ball bearings use larger balls that create significantly less friction and roll longer, creating them great for sustained skating at higher speeds (consider 27-in-5 or banked track). Eight ball bearings have smaller sized balls that greater withstand side loads, which tends to make them terrific for high speed or aggressive turning (think park skating). Derby is often a mixture of all of those things, so come across your magic number!

Serviceable vs Sealed
Serviceable bearings function removable shields or plastic retainers that enable you to clean and re-lubricate your bearings. Most high-end bearings will likely be serviceable to enable you to keep optimal roll and extend the life with the bearing. Sealed bearings have non-removable shields that aid retain out dangerous debris, but they cannot be cleaned and would have to be replaced when not performing as preferred. Sealed bearings are wonderful for all those skaters not thinking about bearing upkeep but have a tendency to lack the efficiency offered by serviceable bearings.