Headset bearings

[Andywinds]

My bearings need replacing, the lower bearing is a 6808RS which I can find easily enough, but the top does not have any numbers on it, I'm able to measure and get the magic three numbers. Do bearing normally come as a set, both upper and lower?

 

[I like Skol]

Does the top bearing actually need replacing? It is usually the lower bearing that takes all the hammering and is also the one that suffers from muck and water ingress. Top bearing is usually as new even when the bottom set are way past their best.

 

[Andywinds]

Does the top bearing actually need replacing? It is usually the lower bearing that takes all the hammering and is also the one that suffers from muck and water ingress. Top bearing is usually as new even when the bottom set are way past their best.

yes, it was very rough. I've found replacements through MB Bearings thanks.

 

[Yellow Saddle]

6808 is a standard deep groove bearing. I find it strange that your headset has such a bearing, since they are very unsuitable to headset use. Most headsets have angular contact bearings (ACBs). What headset is it?

 

[Andywinds]

6808 is a standard deep groove bearing. I find it strange that your headset has such a bearing, since they are very unsuitable to headset use. Most headsets have angular contact bearings (ACBs). What headset is it?

Yes I was expecting the bearing to have more of a tapered side to it. the top bearing does have a 45 degree on one side. They are integrated bearings, so no headset as such.

 

[Yellow Saddle]

Yes I was expecting the bearing to have more of a tapered side to it. the top bearing does have a 45 degree on one side. They are integrated bearings, so no headset as such.

Strange, especially on the bottom.
The reason the top one doesn't have a code like the bottom one is because it isn't a standard bearing with ISO code. These headset bearings are proprietary. Your best bet is to take the sample with you when buying a new one. There are two different angles 36 degrees and 45 degrees, several stack heights, several inner and outer diameters and several differences between inner and outer race height. It is a mess. If you are very lucky it will have an FSA number on it. FSA is an American brand that has some sort of de-facto standard and a set of codes that describes the individual bearings.

As a matter of interest, what sort of life did you get from the bottom bearing?

 

[Andywinds]

About 2k miles. But this is in all weathers, and they were both very dirty and a little rusty looking.

 

[Andywinds]

The bearings came today, the only slight issue I have is with the bottom bearing, the one that came has a 45 degree taper on one side, which does fit in the head better, but because it now fits in slightly further there is more steerer tube. Because of this I cannot clamp down on the head tube bolt enough, will fitting an additional spacer solve this?

 

[Andywinds]

I found an extra spacer and it all fits fine. Comparing the new bearings to the old, the old ones were in bad shape.