Having used 20" wheeled bikes for several years, including in some group rides, I personally would not use a bike with 20" wheels on an "A" ride, i.e. in a fast, rotating paceline. They're just a little too twitchy.

They'd be fine for almost every other type of club/group ride, if the cyclist has sufficient handling skills.


Folding bikes, hybrids, recumbents etc are allowed on NYCC rides. The only limit is that you can't use aero bars.

It's possible that an "A" ride leader might not allow 20" wheels, but that's up to the leader. There's no policy against it.