There is no GRADE lower than ABEC 1, but that doesn't mean that a manufacturer has to meet ABEC standards. There are a lot of small bearing manufacturers that are not publishing any data on their manufacturing standards, so beware. Be aware that the skate manufacturers are not usually also bearing manufacturers. Bearings are often purchased in bulk lots with the purchasers brand name (or whatever name the purchaser requests) stamped on the bearing. Some well known skate manufacturers may be buying their bearings from the cheapest, least quality conscious bearing manufacturer, and you would never know. Buy your bearings on the reputation of the bearing manufacturer rather than that of the skate manufacturer. Stick to bearing brands that are well known and you won't go wrong.

Yes. The other commonly used standard is the ISO (International Standards Organisation) standard. There are slight differences in the standards applied, but basically ISO Grade P0 is approximately equal to ABEC 1, ISO P6 approximates ABEC 3, ISO P5 approximates ABEC 5, ISO P4 approximates ABEC 7 and ISO P2 approximates [ABEC 9 bearings] . Please see our Precision Grades table for the exact values of these precision grades.

Higher precision bearings are designed to allow high precision machinery to operate smoother and sometimes at higher speeds than a standard bearing would allow. Keeping this in mind, a standard ABEC 1, 608ZZ is rated with a limiting speed of 32,000 RPM with grease lubrication and 38,000 RPM with oil lubrication. The actual speed that the bearing will attain without failure also depends on the loads applied and other running conditions but there is really no need to go into that too heavily here.

The ABEC rating of a skf bearing is determined by asking these four questions: 

1.How close is the bore to 8mm in microns (a micron is one millionth of a meter)? 

2.How close is the outer diameter to 22 in microns? 

3.How close is the width to 7mm in microns? 

4.What's the rotating accuracy in microns?

Don't worry if that doesn't mean anything to you - I just wanted to include it in case you're reading this for a paper you might be writing for school!

ABEC isn't the only way to rate skateboard bearings, by the way. There is also the International Standards Organization (ISO) system and the [German National Standards Organization (DIN) system. Here is a chart to help you compare: 

•ABEC 1 = ISO 0 (or "normal") = DIN P0 

•ABEC 3 = ISO Class 6 = DIN P6 

•ABEC 5 = ISO Class 5 = DIN P5 

•ABEC 7 = ISO Class 4 = DIN P4 

•ABEC 9 = ISO Class 2 = DIN P2

We feel that we must stress here that the purpose of higher precision ina bearings IS NOT TO GO FASTER, but (amongst other things) to ALLOW HIGH SPEED MACHINERY TO OPERATE AT FASTER SPEEDS THAN STANDARD BEARINGS WILL ALLOW. PLEASE ALSO READ POINT 6 BELOW.