How/Why lube works


I know you need thin lube for unresponsive yoyos and thick for responsive yoyos. I am not a mechanical person at all, but I would like to understand the difference. The only thing I know is that you want the bearing to spin freely - so why would there be different lubes - what does thick to that thin doesn’t and visa versa? Why does one make it responsive and the other doesn’t?

Hope the question makes sense.


Thick lube offers more resistance to the bearing than thin or even no lube (dry). Think about a couple of bearings in a dry glass. They roll around very easily. Now add a bit of water, They will still roll but less easily. Next try it with some cooking oil. They will not roll around very easily.

Thin vs Thick refers to the viscosity of the lube. Jhb’s example of water & oil works perfectly.

They will both slow down your bearing and make it responsive to an extent, thick much more so than thin.

Thin is used in unresponsive bearings because it helps them run a little smoother, extends the lifespan of the bearing, and keeps that screeching bearing noise to a minimum. It is not necessary, you can play bearings dry, the thin lube is just a maintenance thing and a preference really.

Thick is necessary in most cases to get the desired response for responsive yo-yos, 2A yo-yos especially.


I’ll try my belt

The yoyo construction is based of three separate item, the body, the bearing and the string

In solid axle time, the important is to have a good string tension, too tight, can’t sleep well, too loose can return

The design of bearing is to reduce friction between the body and the string since the direction of the play is mostly long spin trick

So to spin long, the string has to be independent to the body. The string still have higher friction to the bearing outer race, whole the inner race is screw tight to the body

The thing separate both races is the miniscule balls 7-10 depending on brand/model. So the tolerance of there balls between the two races is so tight thats a file of oil is actually impeding the ball from rolling in the race groves.

The lowest friction here is a flat surface against the spherical balls, and usually the groves is in V shaped to hold the balls inflate. Due to the nature of oil sticking to both surface, this making the inner race pulling on the balls, which in turn pull the outer race along with the turn. The string being “stuck” to the bearing this follow too turning into the gap. Enough string will catch on to the response pad and bring the yoyo back up to the hand.

The lower the viscosity, the thinner the oil fill will coat the bearing balls at well at the inner groves. Best unresponsive play is to play dry, but being direct contact, the inner surface at well at the balls does get worn down overall time. Lube help extend by reducing less direct touch between the metal.

so, are we saying the thick lube actually: a) protects the bearings b) makes the bearing intentionally work less well so it is more responsive?

And that thin lube is primarily to protect the bearing and reduce noise (not necessarily to improve play)?


All lube protects the bearing. Yes, the thicker lube slows down the bearing. “Work less??” Don’t know if that’s the proper term. Thin lube does somewhat improve play as it smooths out the spin. A dry bearing will often feel gritty and coarse in my experience.

Lube ‘replaces’ the friction by filling between contacting parts.
To maximize performance, you will need proper lube viscosity. Generally it has to be thick enough to effectively replace friction on rolling or sliding parts so that they wear out less, yet it has to be thin enough to reduce friction or at least keep it at minimum.
Usually bigger bearing require thicker lube, though in yoyos lube is mainly used to reduce noise or to add friction for responsive play. Yoyos are lightweight and doesn’t spin too fast that you can use dry bearings relatively safely without the risk of sudden locking or even exploding.

Makes sense. Thank you