ABEC rating on bearings for offroad racing.
 

So lately I have been doing a little bit of research on the ABEC ratings on bearings. My question is, is there any real benefit to be had from running clutch bearings and wheel bearings with a higher ABEC rating for offroad racing? Or would it be a waist of money to run say ABEC 5-7's?

the rule of thumb back in the day was the higher the abec number the higher the speeds it could handle. with that being said the higher the number the longer it may last.

As a rule it has to do with percision between the outer and inner races.
We use class 5 which is a decent quality and percision for offroad!

here is a link explaining
http://en.wikipedia.org/wiki/ABEC_scale

In most RC applications, we don't get anywhere near sniffing the high RPM tolerances for ABEC-1, let alone 7.

We experiemented with all of the available ratings in both Ceramic and Steel for drivetrain and clutch.

Results --

Ceramic ABEC-3 and ABEC-5 work well for Off-road. ABEC-7 works well for On-road, but we had failures in Off-road applications. For clutch, if you decide to use Ceramic, use ABEC-1. ABEC 3 and up experienced failures due to stresses normal for a clutch. (clutch bell slamming into spur upon hard acceleration or hard landings -- torsional stresses)

Steel, ABEC-1 and ABEC-3 work well for Off-road. ABEC 5 and 7 work well also, but we couldn't see any benefit for that application for the extra cost. For clutch, use ABEC-1 or ABEC-3. ABEC-5 and ABEC-7 experienced failures due to the same reasons above.

Thank you! This is exactly what I was looking for!