Is WD-40 harmful for the bearings?

Hi all,
Do you know if the well known WD-40 spray (for removing rust, lubricating and everything) harms the yoyo bearings?

I know it’s best use the YYJ thin lube or some other thin oil, like sewing machine “singer” oil.
Does this product lubricate the bearing? I know it certainly does something- at least keeps it from rusting, butwhat exactly? does it interfere with unresponsive playing?
Thanks 2 all! (I’m using a YYJ Legacy now)

Yes, it wouldn’t be good considering it has water in it.

What about graphite lubricants?

Graphite Lubricants will slow the bearing down. I would suggest using trumpet valve oil as thin lube.

so I shouldn’t use it because it causes rusting? but it’s made to remove rust. ???
how does it ruin unresponsive play?

WD-40 doesn’t remove rust, it just lubricates things so they can move easier.

The use of wd-40 has been debated for a long tom in the yoyo community.
WD40 does not contain water. The w in the name does stand for water though so that is where the confusion usually happens. Wd-40 actually stands for “water displacement 40th attempt”. It took 40 tries to get the formula right. :slight_smile:
It was originally designed to be sprayed on metal surfaces to remove water and then leave a barrier of oil to keep water out thus preventing rust.
The problem with using it as a lube for yoyo bearings is in the solvent that the oil is mixed with. It is basically mineral spirits. It helps get the oils where they need to be then when it evaporates it leaves behind the oil to do the protecting. This mixture just does not work well with bearing for some reason. After the solvent evaporate the oil that is left is gunky and slows a bearing down pretty bad. I have read on the forums over the past 8 years ago about many people trying and not one of them were happy with the result. I have also heard stories about ruined bearings. I would think that they would not be ruined just gunked up and a good cleaning would bring them back but I have never tried.
I would suggest you take the advice from everyone that has been a round for a wile and skip it and get yourself a decent thin oil. One of my favorites is “Break Free” you will find it in gun shops or sporting shops like “Dicks” that carry gun cleaning accessories. It is very thin so the bearing spins real nice yet it provides a good amount of protection from rust.

Sorry for the wall of text. Hope it helps though.

I just looked up the details on what is in wd-40. At some point they started using carbon dioxide as the propelent. What makes it spray. C02 is an acidic oxide. Yes it evaporates pretty quickly so I dont know how much damage it could do to the bearing but for this reason alone I would stay away. Just found it very interesting and wanted to share with all you guys. :slight_smile:

wow djqsrv thanks a lot.
I guess the WD-40 would be good to clean and protect bearings rather than lubricating them as a thin oil does.

I’ve got a couple of questions though:
Q1- can cleaning also be done with “mineral turpentine”? (it’s a kind of thinner)

Q2- does hair clipper oil (for shaving and hair trimming machines) act as a thin lubricant or is it bad for the bearing? I have some “babyliss lubricating oil” and I think it’s similar to clipper oils like andis or wahl:

WD-40 removes water and then it leaves a lubricant. The problem is that WD-40 has some stuff in it that you don’t need/want in your bearing that you won’t get by using thin lube or valve oil.