I recently got a DM from MikeMonty (thanks!!) and the bearing is unlike the bearings I’ve seen before. I’ve used specs, duncan, and yyj but it is different. On the other ones the cage covers the balls from one side and the other side is open. On this bearing the balls are held in a cage that is symetrical from both sides of the bearing. The cage also only comes halfway up the balls. It has 8 balls so I’m thinking it could be one of the new YYJ speed bearings except the shields did not have any marking on them.
The cage difference is just a style of bearing manufacturing… it has no major advantage/disadvantage fo our use… it’s just different.
Unfortunately most bearings are essentially impossible to identify since they don’t typically carry any unique markings. Only a very small number actually stand out from the rest for various reasons, but those are obvious.
Kyle
The DM’s stock bearing is just weird like that, I know what you’re talking about, no biggie, I just think it looks cooler.
Glad it got to you safely man 
The bearing is a stock yyj bearing, I put the newest one I could find in the DM so you could break it in as you needed, plus it allowed the DM to be responsive for the beginner tricks I was filming, so it was a win win haha
Oh thanks man. I’m really liking it. Mystery solved.
I think that it is a metric bearing because it fits extremely tight on my yoyo seats and it is the first bearing that I’ve had to use pliers to get off my pgm spacers.
If it were a different size of bearing, it most likely wouldn’t fit in your C bearing seat at all. However, you may or may not know this, but most C size bearings come in slightly different size because there is a little bit of tolerance on the machines. This is usually only like .0001 inches or something insignificant like that, but you might notice a slight difference in the tightness it has in the yoyo. It’ll still work fine.
Well It eats my YYJ shims like nothing else because the inner race is stepped and very thin where it meets the shim and I can’t use it on my YYF because it becomes permanently on it. Oh, well.
It eats your shims? As in destroys them? You probably aren’t putting them in right then.
I’ve been using shims for about a year and I know how to put them in. Since they are homemade out of plastic they get pushed out and are bent. I think that a metal or wood one would work though. As i mentioned, the inner race is quite thin, so it doesn’t contact the shim as much and squishes it out.
What kind of plastic? I’ve used several different home-made shims out of old credit cards and they have yet bend at all.
I use an old hastings card. It is pretty thick and sturdy so I think I will by another bearing. No biggie.
The bearing isn’t the problem. I would suggest taking a deeper look into what is causing the problem. Most likely you are just tightening the yo-yo too much and crushing the shims. Try tightening it just until you feel the shims.
I ws gonna say that.
Well I’ll try, but if it does it in my hitman and DM and the other bearings don’t, I think that that is a pretty good indication that it is the bearing. Maybe if you understood what is happening then you could agree. The contact space of the shim and the inner race is so small that the inner race wedges in between the seat post an the shim causing the shim to be deformed.