- Ball & ABEC Grade
Ball & ABEC Grade
Ball Grade and ABEC Rating
Ceramic Bearings are rated in two distinct ways: Ball Grade and ABEC.
Ball Grade (Lower is better)
Ball grade is a rating of the individual ceramic balls. The ball grade is a measurement of the roundness (how perfect) of the ball.
This is the single most important rating of a bearing. If you buy a bearing based on 1 rating or spec, ball grade would be it. Race quality, grease, seal performance & retainer type would follow that in terms of what impacts the speed of a bearing.
Balls are graded as follows:
Steel: Grade 300, Grade 100, Grade 25 (commonly used by Shimano), Grade 10 (Grade 10 is the best quality steel ball we have found)
Ceramic: Grade 10, Grade 5 (what we use) & Grade 3 (Grade 3 is the best quality ceramic ball available but more expensive to produce)
The lower the number, the better quality ball.
Our current VCRC Ceramic bearings use grade 5 balls. This means the ball is round to 5 millionths of an inch. Most steel bearings use balls that are grade 25 and more often even worse.
For arguments sake, say you had a grade 5 steel ball (even though they don't make them that high of a grade) and a grade 5 ceramic ball. While similarly round, the ceramic still has the edge in hardness and durability. The ceramic ball will not deform, flat-spot, crack or wear out. The steel ball will! Not to mention the ceramic ball will clean the bearing race with use, making the bearing faster and much more durable!
ABEC (Higher is better)
The purpose of the ABEC committee (Annular Bearing Engineers Committee) is to establish 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.
ABEC is often misunderstood and thought to be the "defining" rating in a bearing. ABEC simply refers to the overall tolerance of the bearing. Tolerances control the dimensional accuracy of the bearing. This rating is useful for industries where high RPMs (10,000 or more) are used such as machinery.
A better ABEC rating does not impact the speed of the bearing in bicycle applications.
On the same note, some bicycle bearing manufacturers market ABEC 7/9 bearings as their main selling point. While the ABEC 7/9 tolerance is tighter than an ABEC 5 rated bearing, the speed of the bearing will not be any faster.
In terms of cost, there is no difference between the ABEC tolerances in our manufacturing.
ABEC rates the overall tolerance of the bearing.
Bearings are ABEC rated as follows:
ABEC 1, ABEC 3, ABEC 5, ABEC 7 & ABEC 9 (tightest tolerance)
The higher the ABEC rating, the tighter the tolerance of the bearing.
But remember tolerance does not effect the speed of the bearing for cycling as even ABEC 1 or 3 (we use ABEC 5) is fine for bicycle bearings. It is used so that manufactures can match the tolerance needed for their product (machinery, tools, etc.) A piece of machinery spinning at 10,000+ RPMs would require a high ABEC rating, such as ABEC 9.
For cycling a rating of ABEC 5 is exceptional and ABEC 7 is more than any component would ever require. We’ve found ABEC 5 to more than serve our purposes of making the fastest ceramic bearing solution for cycling.
ABEC 7/9 is usually reserved for machinery spinning at 10,000 RPMs or higher.
We conducted numerous tests with our grade 3 ceramic balls using ABEC 1/3/5/7/9 tolerances. We found the results with ABEC 5/7/9 to be virtually the same. ABEC 7 & especially ABEC 9 are very tight tolerances but are beyond the requirements of cycling.
We currently manufacture bearings with ABEC tolerances of 5.
Our grade 5 balls and ABEC 5 tolerance, combined with the high quality race, retainer and seals make the VCRC Ceramic bearing one of the best combinations of performance AND value!