OK so there are a variety of concave bearing shapes:
obviously, pure smooth concave, the “O” of bearing shapes if you will
concave but with a center channel indent for the string
angled down to the middle, the “V” of bearing shapes if you will
the most common type: flat in the center, but the sides angle up, the “H” of bearing shapes if you will. I’d say 80% of the “concave” bearings I encounter are this type
the least common type, a combination of V and H, angled steps in the middle and angles on each side… the “W” of bearing shapes if you will
Are there any other bearing shapes I’m missing here? Yes, flat, but I mean other concave variants I’m missing here? Is there really any play difference in these various types of concave bearings?
It seems the most common kind of concave bearing today, with a flat center but angles on each side is known as “center trac” or CT?
@yyfben2.deactivated was kind enough to post a great response to this elsewhere:
Flat bearings existed alongside dinosaurs. People experimented with grooved bearings. They were cavemen I’m pretty sure. Along came the KK. $30 of string CENTERING joy. Note the CAPS on CENTERING. I don’t like CENTERING. Never really did. It prevents the string from sliding across the bearing when other layers of string are added. Grooved bearings were the worst at this. KKs allowed some slide but not much as everything slid back to the middle. If you were into centering they were better than a groove. Still was some trade-off. CT was an effort to make the best of both worlds. room to slide + some forces keeping your string from the corners and friction. On some tricks this actually hurts you (ie suicides) but for the most, the positives outweigh the negatives. The CT bearing has also been patented. Its shape is produced under license by a few, and not under license by a few also.
Ultimately as a player you will adjust to what you use. I don’t think anyone can thank a bearing for a title won but it all contributes in the end.
It looks like the multi-step concave bearings are called “pixel” bearings?
We know pure concave is dif-e-yo, and the edge angled are “center trac” – also by far the most common type out there in my experience.
Not sure who can claim credit for the “V” shape bearing, or the bearing with the center channel string indent. I did notice that G squared ships all their stuff with the center channel string indent type though!
Pretty sure the Buddha Whipple was the first V shape bearing, I remember when it was first released, I was very intrigued.
Others came later, the YYR DS bearing, the pixel bearing, I think there’s at least one other too.
I think Crucial were the first ones to sell dimpled centering bearings but I’m less certain of that one. There was a company that sold a flat but dimpled bearing too, can’t remember what company though, might be Crucial too actually.
Also, not sure if you’d even consider this a true centering bearing but there’s also the Terrapin “wing-cut” bearing which is basically a super subtle CT bearing.
Personally, my favorite has always been the plain concave KK style bearings. They just feel better than any of the others to me. I definitely see CT’s the most nowadays but I actually like that style of CT bearing the least. For me its KK>multi-step V>V>Trifecta>CT. I actually still remember getting a 10 pack of Chinese KK bearings from @LinksLegionaire for less than $50 almost 5 years ago. I still use those to this day and none of them have died out on me.
