Citizens of New York City aren’t necessarily known for their kindness and hospitality. But apparently the Big Apple’s new bike share program is inspiring the best in folks.

If a bike is suffering from mechanical issues, courteous riders have begun turning the seat around to face the wrong way, a signal to other Citi Bike users to avoid that particular bicycle. There is a built-in wrench button on the bike racks that alerts Citi Bike that maintenance is needed, but turning the seat around is a nice way to give rushed riders a quick heads-up to skip that bike and grab the next one.

Folks on Twitter have started noticing the trend and are spreading the word.

#citibike tip: turn the seat backwards if there's a problem to alert other users. Press the wrench button, too. pic.twitter.com/nYayCseTyS — Brooklyn Spoke (@BrooklynSpoke) June 4, 2013

Saw my first #citibike flat today, but a Good Samaritan had already turned the seat backwards to alert riders. pic.twitter.com/OCYcdS1Rsx — Joanna Oltman Smith (@jooltman) June 5, 2013

Smart @CitibikeNYC social convention @alainabrowne noticed: People turn the seat around to face backward in the rack if the bike's broken. — Anil Dash (@anildash) June 19, 2013

Related: How much of a pain in the ass is Citi Bike? Ask Casey Neistat.