What makes a good ball bearing a great ball bearing for bicycles? Part 2
After discussing the bearing balls in our previous post, we will look further into the qualities that make a great ball bearing. This focus is on radial ball bearings, not so much on cup and cone or angular contact bearings, we will probably cover that in a future post.
Races, or race ways, in most bicycle applications are made of hardened steel. The rings themselves have to be perfectly round inside and out since they have to be pressed into a hub or bottom bracket, fit a crank spindle and have the balls rolling around in them without hitting any bumps or high/low spots.
The inside of the raceways can be polished to achieve the smoothest possible finish, which decreases friction and improves the durability of the bearing.
In the production of Kogel Bearings, the races can only be produced to less accurate tolerances than the ceramic balls due to the material properties. After mirror polishing each race, every set of inner and outer ring are measured and matched up with a matching ball size, according to where the spacing falls in the tolerance. This labor intensive process ensures that we build the best possible bearing.
- Outer race of a radial ball bearling polished to a mirror like finish, courtesy of SKF bearings.
In bicycle bearings, the seals are often overlooked. There are many options, ranging from fully open to heavy duty double lip seals. With the amount of protection, the friction goes up.
Kogel Bearings is one of the few companies to our knowledge that offer different seals for different applications: a non-contact seals for road racing and a heavy duty seal for Cyclocross and Mountain Bikes.
- Different seals for different environments. Kogel Bearings uses green seals for heavy duty cross seals. Blue seals indicate low friction road bearings.
Looking at grease, there are two major factors to consider: the viscosity of the grease (aka ‘thick’ or ‘thin’ grease) and the filling degree of the bearing. As a rule of thumb: thick grease and fully packed bearings make for high durability and high friction. The balls need to fight their way through the grease when going around in circles. Thin grease and a low filling degree make for low friction, but will require to service the bearings more often.
There is a whole range of additives that can be mixed with a grease formula to manipulate friction. If you are interested in getting into the nitty gritty of it, here is a pod cast by Cyclingtips.com talking to industrial lubricant formulator Kyle Mc Bride and Jason Smith of Friction Facts.
What is the best ball bearing for bicycles?
In conclusion, is it possible to pick the best bearing for bicycles? The answer is yes, but depends fully on what you expect. First consider your environment and expectations. Weekly mudfests during CX season require another ball bearing than winning the scratch race on your local velodrome. Price might also be a factor you want to consider. As with complete bicycles, the range is huge. A set of bottom bracket bearings can set you back anywhere between a couple of bucks and a couple of Benjamins.
Once you have determined what your ideal bearings look like, it might be hard to find them. Rarely do ball bearing producers advertise how much grease or what kind of seals they use. Our best advice is to ask questions: to your riding buddies, to bike shop employees and the ball bearing companies. If you have any questions about Kogel Bearings, we’re here to answer them.
If you have any questions about Kogel Bearings, ball bearings in general or our Ball Bearing Adventures, please ask them via the 'Need Help' button at the bottom of your screen, one of our social media channels or by email via email@example.com. We will answer them in a highly professional, but not always scientific way. We do not shy away from many subjects. Please ask, we are here to answer.