This page was created with information contained from several posts to various yo-yo webboards by Jim Pankey (`5). Thanks to Jimbo for going to the effort to compile the information and for giving me permission to post it here.
After wondering what ABEC was and being asked a couple of times I went looking for an answer. I found out first what ABEC stands for.
Annual Bearing Engineers Committee
What is that?
"Precision ball bearings are manufactured to standards established by the Annual Bearing Engineers Committee (ABEC) of the Antifriction Bearing Manufacturers Association (AFBMA). They have been accepted by the American National Standards Institute (ANSI) and conform essentially with the standards set by the International Standards Organization (ISO). "
Maybe that will help... maybe not, but it gives a slight idea as to what the ABEC means when you see it. Basically ABEC is a grading set up to identify and set dimension tolerences in the manufacturing of bearings.
I also discovered what ABEC does not cover:
"ABEC and ISO Standards do not cover the following factors: Radial Play, Raceway Curvature, Roundness or Surface Finish, Material, Ball Complement, Number, Size or Precision Level, Lubrication, Cleanliness at Assembly or Packaging, Retainer Design. "
Where did I find this?
http://www.dynaroll.com/index.html
The company is Dynaroll and they make:
"Miniature and instrument grade ball bearings (ISC Micro Precision), High precision subassemblies (computer peripheral, medical, aerospace, etc.),
Analytical test equipment for torque, runout and other mechanical properties"
Some questions addressed...
Is there a lower grade than ABEC 1 ?
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 Yoyo Manufacturers are not Bearing Manufacturers. Some well known Yoyo Manufacturers may be buying their bearings from the cheapest, least quality conscious bearing manufacturer. Buy your bearings on the reputation of the Bearing Manufacturer rather than the Yoyo Manufacturer. Stick to bearing brands that are well known and you won't go wrong.
Some friends have bought ABEC 9 bearings and they tell me that it definitely increases speed. Why do they believe this ?
I'm not psychologist but I can think of 3 reasons immediately. Firstly, if you had just paid $20.00 for a bearing, you too would "believe" that they were better than what you had bought previously for around $3.00 to $4.00. Secondly, and somewhat similarly, if you really believe that something will make your yoyo faster, it probably will (it's all in the mind). Thirdly, how do you seriously compare the speed at which your new ABEC 9 bearing allows you to spin against the speed that your old ABEC 1 bearing allowed you to spin several months ago when it was also new ? More likely you would be comparing against the speed at which the old ABEC 1 bearing allowed you to spin after it had worn considerably. Try this in reverse. Take out the old ABEC 9 bearing after several months and replace it with a new ABEC 1 bearing and you will get a similar increase in speed.
What features of a bearing are covered by the ABEC standards?
ABEC standards cover the tolerances of all of the measurable dimensions of the bearing (except the radii). Refer to the chart in our Technical Section for specific values. ABEC standards do not cover Running Noise, Starting Torque, Lubricants or Clearance.
Why is there so much hype at the moment about ABEC precision ?
A problem with the industry is that too many bearing sales people don't know enough about the product that they are selling. People with over 20 years experience in the industry still get scared when a customer starts to ask about load ratings, limiting speed, internal clearance and yes, you guessed it, ABEC precision. What has happened here is that someone has been told a basic fact that higher precision allows for higher speed (and this is true under certain conditions). Not fully understanding this, the information has spread and gained momentum (mainly through the Internet). There are many more inexperienced people in the bearing industry than there are experienced people and this has allowed for rapid growth of this falsehood.
What are the grades of bearings available in order. How different are the grades ?
OK, but don't forget that you really do not need to waste money on anything higher than ABEC 1 or ABEC 3 for yoyoing applications. It should also be pointed out that the precision grade only tells us how close the bearings dimensional tolerances are (that is, how close the bearing is to the stated size). There are many other factors relating to the quality of a bearing, and many of these factors will have much more of an impact on your skating experience than the ABEC Grade of the bearing.
From Lowest to Highest
ABEC 1 Approximately equal to ISO P0
ABEC 3 Approximately equal to ISO P6
ABEC 5 Approximately equal to ISO P5
ABEC 7 Approximately equal to ISO P4
ABEC 9 Approximately equal to ISO P2
There are a number of factors covered by the ABEC grades, but to give you an idea I will just examine one of these factors - the eccentricity (out of roundness) of the track in the inner ring. For an ABEC 1 (lowest grade) bearing, the maximum eccentricity allowable is 0.0075 mm (0.000295"). This is quite precise - more than precise enough for yoyos. The figures for the other ABEC grades are 0.005 mm (0.000197") for ABEC 3, 0.0035 mm (0.000138") for ABEC 5, 0.0025 mm (0.000098") for ABEC 7, and 0.0012 mm (0.000047") for ABEC 9. If used in high precision, high speed machinery, these minute variations can make a difference. The fact is that no matter which of these bearings you use in a yoyo, after a little use the tracks won't just be eccentric, they will become irregular (albeit minutely) enough to be practically indistinguishable from one another. Your high priced ABEC 9 bearing might as well be a 50 cent ABEC 1 cheapie.
(Information gathered from - http://www.minibearings.com.au/skate.htm )
Information Compiled By Jim Pankey (`5)