How often to replace bicycle wheels?

Answer 1

Don't rightly know what you're referring to here...

Bike tires will eventually crack and go brittle by age and need replacement because of that. They can also get damaged by road debris to the pint of needing replacement. They can burst by over inflation. The tubes inside can also go bad by age, but that usually takes decades. Tubes can easily be patched up if punctured, but there comes a point where they too will need replacing.

Rims will eventually wear out, if it's a rim-braked bike. But that also takes years unless you ride a lot in muddy terrain. Hard impacts or potholes can damage a rim, but that's pretty much self- indicating. Too high spoke tension can cause a rim to crack around the nipple bed.

Hubs can go pretty much forever, assuming they get a marginal amount of care and attention. Hubs that takes cartridge bearings will need to have the cartridges replaced eventually while good quality cup&cone bearings can last pretty much forever if lubed and cleaned every few years.

Front wheel spokes will also last pretty much forever, assuming you're not getting anything stuck in your front wheel. Rear wheel spokes can be a bit of a consumable item for bikes with external gears, poorly built wheels and/or heavy, powerful riders.

The short answer is - if it ain't broke, don't fix it, there's no set value for time/mileage after which the bike wheels needs to be replaced. Check for damage and/or changes, and ride until either occurs. Only exception would be if you want to be certain of getting the best traction all the time, in that case - replace tires yearly.