iYoYo Slim Bearing / Half-Spec – narrow bearing for responsive YoYos

Dave’s take

“First of all, the most important thing: in 99% of cases, you will never need to replace this bearing. A Slim Bearing is not a typical wear item that needs to be replaced regularly.
We mainly sell it separately because bearings sometimes disappear under a cupboard while you are converting or cleaning your YoYo. :-) So if you have lost the narrow bearing from your beginner setup, this is the replacement you need.”

Dave Geigle · 5-time European YoYo Champion · Playing since 1997

• Mainly a “I lost mine” spare part → your existing Slim Bearing will normally last a very long time and does not need regular replacement

• Made for responsive play → allows compatible YoYos to return with a tug on the string

• Half-Spec construction → same outer diameter as a standard Size C bearing, but considerably narrower

• Narrower gap → lets the string reach the response pads more easily for more direct response

Does a Slim Bearing need regular replacement?

No. Unlike YoYo strings or response pads, a bearing is normally not a spare part that needs routine replacement.

If your Slim Bearing is still there and works, you can usually just keep using it. Even if its behaviour changes slightly over time, that does not automatically mean it is broken. In a responsive setup, the bearing is not supposed to spin as freely and unresponsively as possible anyway.

This replacement bearing is therefore mainly intended for a very practical situation: you lost the original Slim Bearing while converting, cleaning or storing your YoYo.

What does Half-Spec mean?

Most modern string-trick YoYos use a full-width Size C bearing. A Half-Spec Bearing uses the same large outer diameter but is significantly narrower.

This allows the two YoYo halves to sit closer together and creates a narrower gap. The string can reach the response pads more easily – exactly what we want from a responsive YoYo.

The YoYo can still sleep and perform proper tricks, but it returns to your hand with a short tug on the string.

Narrow bearing = responsive, wide bearing = unresponsive

On many modern beginner YoYos, changing the bearing also changes the way the YoYo plays.

With a Half-Spec Bearing, you can start with responsive play. Once you have learned the Bind, compatible models can later be converted to a full-width bearing. The wider gap reduces contact between the string and response system and enables modern unresponsive play.

This is exactly how the iYoYo SHOOTiNG STAR works: the slim bearing is used for the beginner setup, while the wider Pixel Bearing converts it to unresponsive play later on.

Important: not every YoYo can simply be converted

A slim bearing should only be used in YoYos designed for it. Bearing width, axle length and bearing seat all need to work together.

If your YoYo was designed exclusively around a full-width bearing, do not automatically install a Half-Spec Bearing.

Bearing Size: C / Large – Half-Spec / Slim