I don't know about 55 but I did get a good idea from some friends of my mother. Of their own volition, they moved to a residence that was popular with senior citizens and had optional levels of assistance, from none to a lot. Their reasoning was that if their health started to fail them they could get help without burdening their family or dealing with the added trauma of having to move out of their home. I'm guessing they were in their late 60's to mid-70's when they did this.

As far as riding goes, I'd do it as long as you can. I have a friend in his 60's that still does long distances races and can average 20+ mph. I knew a guy in his 70's that rode from Minnesota to New York one summer with his daughter.

Deciding when to retire depends on your financial circumstances and how you'd spend your time if you weren't working.

I like my job but it comes with a certain amount of stress and I'd certainly love more free time. Retiring at 55 doesn't sound like the worst idea to me. We have neighbors who became teachers in this district at a time when teachers were hard to come by. Early retirement was part of the deal so they finished teaching when they were 55. He has a job/hobby framing pictures and she still works for the schools on a part time basis, or at least she did for awhile. I don't think they regret retiring.