I noticed the bearings on my rear wheel aren’t as smooth as they used to be - like a grinding feel to it. Nothing too serious though, and they still spin freely (i.e., spins over a minute from a light nudge).
I’ve put fresh grease on them but got me thinking if replacing bearings has a significant impact. I am able to spin it for quite a long time using my thumb, which surely isn’t much power, right? Or is it?
How many watts, if any, are lost from non-premium-but-highly-usable bearings?