Why do men's bicycles have crossbar and women's do not?

Answer 1

Back in the day, men would have passengers sit on this bar. The guy's gal would sit side-saddle on the bar and be able to be transported here and there.

I've also heard that the bar makes the frame stronger and that it was eliminated in girl's bikes so that they could ride while wearing skirts.

The right answer has to do with modesty. Back in the days when the bike was invented it wasn't seen fitting for honorable women to show their legs in public, so the step-through/ ladies-specific bicycle frame was developed.

This was the era that also saw the invention of the side saddle for horse riding.

Then the habit stayed on, and became the preferred design for people of both sexes who wanted a bike that was easy to get on and off.

Frames with a top tube(sometimes called cross bar) are stiffer than Step-through frames which is the main reason why that design dominates the racing scene. (another reason is that UCI, the big governing body for bike racing wants it that way).

Suspension MTBs might look a little like anything, the suspension elements changes the design constraints for the frames.

Answer 2

Bike frames with crossbars(AKA top tubes) are generally stronger/stiffer/lighter than bike frames w/o them, but back in the day when the bicycle was invented it was indecent for a woman to show her legs in public (they all wore long skirts). So bike frames were made w/o the top tube so that they could be ridden by women in long skirts.

Although no one cares about women exposing their legs in public these days, the tradition of "mens" and "womens" bike frames have lived on.

These days though you can see both performance oriented women riding"mens" bikes, and comfort oriented men using "womens" bikes.

Answer 3

Classically, boys bike frames/wheels are bigger and the frame has a crossbar

Answer 4

Once upon a time ... boys wore pants and girls wore skirts.