Why do you need shields or seals on your ceramic bearings?

We all enjoy our ride in the outdoors whether you are riding a road bike at speed on the high roads or a mountain bike in the wilderness. While we are having fun out there, our bikes will be no doubt exposed to external factors such as rain, puddles, dirt and dust. These external factors will first affect the motion parts on your favourite bike especially on your bearings.

As we are trying to improve our riding experience and also our bike performance, we tend to look for ways to upgrade our bikes. Whether on ways to make our bike faster, tougher or more good looking, we are open to different ideas out there.

One of the smallest upgrade of course is to change stock jockey wheels to ceramic ones. Watching the smoothness of the ceramic jockey wheels spin, other than feeling therapeutic, we also know by installing these ceramics in our bicycle, our ride can feel butter smooth. 

There are many brands out there providing this small upgrades. From the expensive ones to the ones you can get cheaply from Aliexpress or Ebay. Depending on how much your wallet can afford, you will choose the option most suited for you. However, many 1st timers tend to go for the cheapest option first just to "test it out". Either this cheap option fails you and you just give up on this upgrade or you will pay the high amount for the branded ones.

Now what is the difference between the cheap ceramic bearings comparing to the branded ones? Below is a picture comparison.

As you can see, the difference between a branded ceramic bearing comes with seals whereas the cheaper bearings are exposed. After riding for a short period of time, dirt and grim will start to cog up these bearings causing them to fail prematurely. This is a critical design flaw on these cheap ceramic bearings.

Why don't they include the seal? 

Cost!! As this type of bearing size is considered in the bearing industry as miniature bearing,  it is very difficult and expensive to input the seal onto such a small bearing. In order to keep cost down, they tend to omit the seals altogether. 

Below is a short video on bearings without seals or shields and the effect on your riding performance. We will like to give credit of this video to TraceVelo. 

Why waste your hard earn money on something you know will fail? Well, this is something for everybody who is looking to upgrade your jockey wheels to think about.