Why we have high ABEC bearings in skateboarding.

A typical scenario.....

A skateboarder went into a bearing shop and asked the question
“What is the fastest bearing you do?”
The salesman thought for a while and said
“ABEC 9, but they are very expensive”
Unfortunately, due to the language barrier between them this has resulted in the current market situation.

“Fastest” in skateboard speak is “Lowest torque” in bearing speak.
“Fastest” in bearing speak is the bearing that has the highest RPM before failure.

The difference between an ABEC1 bearing and an ABEC9 bearing is ONLY the tolerances to which it is made. An ABEC1 bearing is not made to as close a tolerance as an ABEC9 one.

The differences between them are measured in microns or thousandths of a millimetre. The bore (the hole in the middle) of a skateboard bearing is 8mm. For an ABEC1 bearing the tolerance band on the bore size would be between 7.9920mm and 8mm. For an ABEC9 bearing the tolerance band on the bore size would be between 7.9975mm and 8mm. This is a difference of 5.5 microns. The human eye can only see things bigger that about 45 microns (roughly half the thickness of a human hair). That’s 8 times bigger than the differences between the two bearings!

One good 5 set ollie will probably change the shape of your bearings by more than that.

The reason an ABEC9 bearing feels faster is that they are usually filled with oil and not grease, i.e. nothing to do with the precision of the bearing. The following table illustrates maximum revolutions per minute (RPM) with increasing tolerance (ABEC number).

608 (the primary bearing size used in skate boards)	Max rpm in grease	Max rpm oil
Max RPM 608-ZZ ABEC1 (1.0)	34000	40000
Max RPM 608-ZZ ABEC3 (1.1)	37400	44000
Max RPM 608-ZZ ABEC5 (1.2)	40800	48000
Max RPM 608-ZZ ABEC7 (1.4)	47600	56000

Taking this a little further.....

An ABEC 1 has maximum RPM before failure if lubricated with grease of 34,000 RPM - grease being the slowest rating due to heat build up and churning drag. Assuming the worst possible case of wheel outside diameter of 40 mm.

1 revolution = 40x3.14 = 125mm of travel (roughly)

Therefore a wheel travels in 1 hour 34000x60x125 = 255,000,000mm

This is 255 km/h or roughly 160mph!!!!

An ABEC 7 can allow for 56000 rpm – they are usually sold oiled not greased

Assuming the worst possible case of 40mm diameter wheels.

1 revolution = 40x3.14 = 125mm of travel (roughly)

Therefore wheel travels in 1 hour 56000x60x125 = 420,000,000mm

This is 420 km/h or roughly 260mph!!!!

Wheels normally overheat and fail at about 100mph due to bubbles in the urethane bursting due to heat build up.

Finally the high accuracy of a component is only of use if the surrounding parts are of a similar accuracy. All skateboard trucks and wheels are made to NO WHERE NEAR the standards of the bearings so fitting high ABEC bearings in a skateboard is akin to fitting Formula 1 wheel bearings to a tractor hub.

Although the above may not be popular to many who sell high ABEC rated bearings at highly inflated prices, it is designed to dispel many myths and false selling when it comes to your skateboard bearings.

So now you know.....

In normal skateboard conditions there will be no difference between skate bearings of differing ABEC ratings when set up identically. The differences that you can feel occur due to method of sealing and type of lubrication. The only other major difference that exists is in the quality of the materials used to make the bearing but this cannot be measured without dismantling a sample bearing and putting it through some pretty expensive tests.

For further information on skates vist our skateboard links page.