We carry grade 25 bearing balls in the popular bicycle sizes. Grade 25 is the highest quality commercially available, as used in Campagnolo Record and Shimano Dura Ace parts:
Many parts come with balls in retainers. There are two advantages to the manufacturer for using retainers:
Generally, when overhauling hubs or bottom brackets that come with retainers, it is better to use loose balls. It's a bit trickier to install them, but you will generally get better performance and longer component life if you use loose balls.
- They can use fewer balls, so they actually save money on that.
- Assembly is faster and can be done by automated machinery, also saving costs.
There are a few exceptions to this, mainly cases where assembly with loose balls is exceptionally difficult. These would include headsets, one-piece-crank bottom brackets, coaster brakes and internal-gear hubs.
Bearing balls are made to extremely high precision within each production batch, but there are typically slight size variations between one production run and another of the same nominal size.
For this reason, you should never mix batches of bearing balls. If you have some that are a little bit bigger and some that are a little bit smaller, the bigger ones will be doing all of the work, and the smaller ones might as well not be there.
Generally, when overhauling a loose-ball assembly, good practice is to throw away the original balls and replace them all with new ones from the same production batch.
|1/4"||25||Bottom brackets (11 x 2)|
Most rear hubs (9 x 2)
|7/32"||25||Campganolo record front hubs (9 x 2)|
|3/16"||25||Most front hubs (10 x 2)|
|Articles by Sheldon Brown and others|
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