With ball bearings you also have different types of ball bearings. You'll notice here, this bearing is quite small. It's a little bit thinner and on the axle itself compared to this one, you can see the diameter over itself is pretty small. So there's different sizes. Sometimes the larger they are, the easier it is to keep them spinning longer 'cause they make a wider gap, it won't grab the string quite as fast and you'll really get some good spin time out of it. When it comes down to it though, small versus large bearing, it doesn't make the hugest difference in the world, I won't freak out if you have a small bearing yo-yo and I don't think that you need a large bearing yo-yo for things to work. The next step from a regular bearing is something called a concave bearing.

And if you zoom-in on this bearing, you can actually see it's got a little groove in it if you compare it to this one. Because of that little groove, the string can actually sit right down into that bearing and what that allows you to do is it allows the string to sit there and it won't get caught by the edge of the yo-yo quite as well and it also centers it so when you're doing tricks on the string, the yo-yo moves to one side or the other. It's not going to as quickly grab the edge of the yo-yo. It's going to be centered there. It allows you to do tricks at much longer time, allows everything to keep smooth and what not. So those are your basic types of ina bearings. You can also get different ABEC ratings, there's ABEC five and seven just kinda like skateboards. There's even ceramic bearings. Ceramic bearings spin for an incredibly long time, it's not incredibly needed though. If you just get your basic ball bearing with your yo-yo, it should be enough and with a little lube and cleaning which we're going to be talking about in the next segment, you can make it play as good as it needs to be.

In bearings of this type, the cylindrical rollers are in linear contact with the raceways. They have a high radial load capacity and are suitable for high speeds.

There are different types designated as NU, NJ, NUP, N, NF (for single-row bearings), NNU, and NN (for double-row bearings depending on the design or absence of side ribs).

The outer and inner rings of all types are separable.

Some cylindrical roller skf bearings have no ribs on either the inner or outer ring, so the rings can move axially relative to each other. These can be used as free-end bearings. Cylindrical roller bearings, in which either the inner or outer rings has two ribs and the other ring has one, are capable of taking some axial load in one direction Double-row cylindrical roller bearings have high radial rigidity and are used primarily for precision machine tools.

Pressed steel or machined brass cages are generally used, but sometimes molded polyamide cages are also used.Depending on the existence of ribs on their rings, Cylindrical Roller Bearings are classified into the following types:Types NU, N, NNU, and NN are suitable as free-end bearings. Types NJ and NF can sustain limited axial loads in one direction. Types NH and NUP can be used as fixed-end bearings.

NH-type cylindrical roller bearings consist of the NJ-type cylindrical roller bearings and HJ-type L-shaped thrust collars.The inner ring loose rib of an NUP-type cylindrical roller bearing should be mounted so that the marked side is on the outside.Rolling bearings fall into two main classifications: ball bearings and roller bearings. Ball bearings are classified according to their bearing ring configurations: deep groove, angular contact and thrust types. Roller bearings on the other [bearings types] are classified according to the shapeof the rollers: cylindrical, needle, taper and spherical.