I recently noticed a strange "sand paper feeling and noise" when turning the wheel of my bike, and decided that it was time to learn to service the bearings of the hubs (cups and cones bearings, not sealed ones).
I have few questions related to this:
- Is it normal wear, or can it be avoided by more systematic maintenance? - if the info is relevant to answer, it's the side with the brake rotor, the other side has a discolored mark, but is smooth.
- What would be the cause, ingress of dust/sand in the bearings? (I'm riding between 200km and 400km per month, mix of road, gravel (dusty) and light forest trails, the bike is almost 2 years old), almost only dry. There was still a fair amount of grease in the bearing.
- I couldn't find a matching parts on large online bike shops: is this part part of a wider standard and can I find only the cone, or I should I replace full bearing? (cone/cup/bearings). In the second case, what would be the "key measurements" to consider when looking for bearings? (I didn't find the info on Formula's website - the hub is a formula DC20/22 according to the spec sheet of the bike).
- If finding parts is difficult, are there consequences of continuing to use the wheels/hub? (except accelerated wear?). Before this discovery, I was actually considering buying a second pair of wheels and keep the current ones for winter/spares.
- [ADDED] I also noted clear bearing marks on the cone — I lock the suspension when riding on roads, would it be possible that a shock has cause such markings (not speaking about the fine marks that can be caused by sand)?