What are bearings?
Bearings are crucial components that support the rotating parts essential for a bicycle to move.
The internal structure is quite simple.
Hard balls are placed where the bearing is housed, and as these balls roll along the race, they allow the component to rotate, creating a structure that reduces friction in moving parts.
What kinds of bearings are there?
There is an enormous variety of them; their overall size, shape, structure, and the size, number, and shape of the balls inside change depending on their intended location and purpose.
If you take a quick look around the pit, you'll see balls rolling out everywhere.
The main types of bearings used on bicycles are:
・Sealed bearings
・Retainer bearings
・Cup and cone bearings
These are the most common ones.
Sealed bearings have become increasingly common in recent bicycles. The reason is that, as the name suggests, they are structured to seal the balls, providing far superior rotation, oil retention, and durability compared to bearings with exposed balls.
However, due to their structure, sealed bearings cannot be disassembled, cleaned, or maintained.
In other words, they are disposable.
Even if they are inexpensive parts, it’s a bit sad that they cannot be repaired.
For more on sealed bearings, please see our previous tip: "[PIT TIPS] Round and round the bearings go".
So, what about Chris King bearings?
In a word, Chris King bearings are sealed bearings that allow for maintenance.
While standard sealed bearings cannot be disassembled, Chris King bearings can.
Being able to disassemble them means they can be cleaned and maintained, and if any parts are damaged, they can be replaced.
This embodies Chris King's desire for products to be used carefully for a long time.
So, what are the benefits of repeating cleaning and maintenance instead of using disposable bearings?
It's that you can actually improve their performance by using them over a long period.
In Japanese terms, you might call it "breaking in" or "settling in."
As smooth metal surfaces rub against each other, they become even smoother.
This smoothness creates better rotation, but if you don't clean away the metal shards produced during this process, they will eventually move past the point of smoothness and damage the body itself.
That is why they created a bearing that is both highly sealed and capable of being cleaned and maintained.
Chris King bearings are manufactured entirely in-house, setting them apart from manufacturers that simply assemble other companies' sealed bearings to create rotating parts.
Exploded view of a Chris King bearing
So, how are Chris King bearings constructed?
Let's take one apart.
① First, remove the snap ring using a tool like a dull design knife.
② Remove the seal located under the snap ring you just took off.
③ Push the retainer out from the bearing body.
It only takes this much to break it down into four parts:
the snap ring, the seal, the retainer, and the bearing body.
Carefully clean these four parts, grease them up, and reassemble them in reverse order, and maintenance is done in no time.
Moreover, this full disassembly is only necessary during a complete overhaul.
Under normal circumstances, you can leave the bearing pressed into the hub, simply remove the snap ring and seal, and clean them—it's that easy.
They say that excellent industrial products are designed with maintenance and ease of disassembly in mind, and you can really feel how high the level of Chris King bearings is.
By repeating this cleaning and maintenance, the parts can be used for a long time.
For example, the Chris King headset I bought 20 years ago is still in use today without any damage to the bearings.
So, how about performing some maintenance on the Chris King parts you own?
You’ll gain even smoother rotation.