Also consider a folding bicycle, as most lack crossbars altogether - and are also easier to transport by car.

It didn't: his folding bicycle was considered too quirky.

For some years already he had been researching the idea of a truly effective folding bicycle.

A folding scooter can be more easily carried than a folding bicycle or even a portable bicycle.

Each of these were noted to be distinctive design decisions that another manufacturer could change without compromising the ability to create a functional folding bicycle.