True and there's no need to keep a horse racing when it's good days are almost behind it. I've heard it said that good racers are mostly used to breed, when they are done racing.I've just realised I didn't answer the question. For most racing horses it is around 5-7 years, although there are outliers. Geldings may race until 12 years or older. New York has a legal limit of 14 years, because as the horse gets older the injury risk increases.