THE REEL MECHANIC - Measuring Reel Spool Shaft Bearings

"Use Your Browsers Back Button To Return"

Measuring Bearings

So you want to replace or upgrade your reels spool shaft bearings. We hope this article will help teach you how to measure them.

Well lets get started.. First things first, you will need a set of calipers you can read. As you can see from the image below there are a few different styles. I prefer the digital set, I set it to read in millimeters so we will be using it to illustrate with.
Bearings listed in our supply shop and other shops are listed by Inside Diameter x Outside Diameter x Width.

The bearing that we are using for illustrative purposes is a 5x11x4mm bearing.
In this image we are measuring the inside diameter we set the bearing onto the top points and open the caliper. As you can see the calipers are reading a measurement of 4.93mm (actually it is bouncing between 4.93 & 5.0mm. So I round the measurement up to the nearest millimeter, this is the 5mm in the 5x11x4mm.

In this image we are measuring the outside diameter, we set the bearing onto the bottom jaws and close the caliper. As you can see the calipers are reading a measurement of 10.99mm. So I round the measurement up to the nearest millimeter, this is the 11mm in the 5x11x4mm.

In this image we are measuring the width, we set the bearing on it's side onto the bottom jaws and close the caliper. As you can see the calipers are reading a measurement of 3.98mm. So I round the measurement up to the nearest millimeter, this is the 4mm in the 5x11x4mm.

Thanks for following along and I hope this helps you understand the bearing measurements and how we get them. Now when you decide to upgrade your reel/s to some ABEC5 Stainless Steel bearings you will know exactly what size's you will need. Remember the only bearings that affect your reels casting abilities are the 2 or 3 spool shaft bearings (always check the reels schematic for bearing placement). All other bearings in a reel are for cranking smoothness and comfort...