I like to drop the fork every year just for a good look-see. Have several years on the OEM headset and the bearings seem fine. I also pull the caliber brakes for a good cleaning. I replaced internal cables ONCE and won't do it again unless I have trouble. (At least the FD cable took me a couple days to get in.) I do pull cranks now and then for deep cleaning. I also have WM screw together BB30 and removing the cups is simple (haven't touched the bearings). I have in the past removed seals from cartridge bearings, but I think it's not worth it if you can get the bearing out easily and replace. That's what I've done on hubs.
scott s.
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