Yo-yo bearings are mostly deep groove ball bearings made of bearing steel, with inner diameters ranging from 3 mm to 6 mm. Most of them are open and some are sealed. Special long ball bearing belongs to non-standard English bearing, also known as KK bearing, and its excircle is U-shaped.

2. Different characteristics

The biggest advantage of KK bearing is that the design of U-shaped groove conforms to the use characteristics of yo-yo, which makes the speed of yo-yo stable. Ball bearings are characterized by high speed.

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Maintenance Skills of You You Ball Bearings

Bearings will rust when used for a long time, so they should be cleaned with special cleaning agent. You can clean the yo-yo ball bearing you just bought with a paper towel or cotton swab, and then drop a few drops of yo-yo lubricating protection oil on the bearing ball, which is usually wrapped inside (you can pry the edge open and then drop it, but you can directly fall into the seam for safety reasons). Be careful not to drop too much, just one or two drops, or drop them in other places, so as to lubricate and avoid rust.

Baidu Encyclopedia-You You Ball Bearing