So yesterday I cracked 15,000 miles since 10/04 on my bike. Other then the chain, cassette, and other consumable parts all are original: cranks, bottom bracket, chain rings, derailers etc - frame was replaced due to a crack 3 weeks ago.
What components should I think about replacing based on “rules of thumb”. In general I have no complaints about the ride of the bike or it’s performance, I just don’t want to be in a race and have something decide to go - or be losing out on gobs of power because of worn out parts.