Road bike. Mostly used on roads but occasionally used on loose rock roads.
If they feel rough, it is too late. Plan to do it once a year, more often if you ride a lot in the rain and dust. I ride 2-3k miles a year. If the ball or cones are pitted, replace them for a few bucks before the hubs get damaged. If you are not very concerned with top notch performance of your bike you can wait longer but a buck of grease can save you lots of grief.
You can go a very long time without touching the bearings. If you have sealed bearings they will last years. I remove the wheel and turn the axle with my fingers. If they feel rough its time to clean and repack. Sealed bearings last longer you just replace them.
Sorry to have 2 assist you be attentive to u can not p.c.. the bearings there sealed bearing . I even have been engaged on autos for 18 years. in case you have a automobile that that has packable bearing u will can see many small ball of nevertheless as be attentive to or call stillys or bearing . i worked on a save away from Charger 2006 it had a race that the ball bearing have been save there bearing in place all of it rely on the make of the autos what they used interior the making of the autos
If the bearings can be serviced, about once per year. If they are sealed bearings, you replace them when they start to fail. You can also disassemble and service your hubs yearly. How this is done depends on the specific hubs you have
