Size A Bearing

So, I have a Duncan Speed Beetle, which is a nice, inexpensive starter yo-yo. I’m looking at the bearing however, and there’s no way to get into it to lube it up. It almost seems intentionally designed such that once the lube in the bearing wears off, it’ll stop being responsive and there’s a shield over the bearing race that appears to be good for not much more than preventing the owner from adding lubricant.

To add to the issue is the fact that Duncan appears to attempt to keep players in the dark by assigning letters to their bearing sizes, rather than listing the sizes.

So I might be looking to replace this bearing. Duncan says it’s a size A bearing.

I believe that means it measures 5mm x 10mm x 4mm. I’d like to look into getting a new bearing (one that doesn’t have a shield, so I can lube it).

Am I right that the dimensions of this bearing are 5x10x4?

Am I also right that Duncan seems to have done this on purpose to both force a player to replace the bearing (by not being able to lube it), as well as obfuscating the dimensions so that you have to buy it through them?

A lot of companies use letters as the sizes, 99% of unresponsive yoyos use size C bearings. You can find size A bearings sold on this site.

And the shields on the sides of the bearing aren’t to prevent you to put lube in, it’s to prevent dust and other things to get into the bearing. Naturally this makes the bearing last longer, but if you need to put lube in you can remove the shields. I’m sure you can find a video showing you how to do it if you google it up.

Good to know on all counts.

For the record, my yo-yo is supposed to be responsive, but the friction pads wore off and I took them out completely while waiting for the new ones to arrive. Oddly, it functions about the same without the pads as it did with the worn down pads still in it, so I strongly suspect that was indeed what was wrong with that yo-yo.

That’s probably why it’s a size A bearing. It’s not actually supposed to be non-responsive. It’s a Speed Beetle (Duncan Imperial with a ball bearing).

Thanks again.

I always lube my bearings with the shield on. Just a drop or two between the shield and inner race, the lube will start seeping inside. Having to deshield the bearing when lubing is just too much work, unless if I wanna use grease.

Yeah, that’s how I’m feeling right now. I have a stick pin and I can’t even get in there to pop it open anyway. Maybe letting it seep is the better mousetrap.

Thanks, Rizki.

Yes that’s the size.

You can lube it with the shields on or just pry them out and throw away.

Most places that sell yoyo bearings sell them as “A” or Duncan bearings. Other sources sell them by the dimensional size.

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