Although the frame clearly shows that there is space for a gearbox, the Motobecane is reassembled as a MB1. To make it a MB2 model there are some changes required:
The flywheel of the MB1 isn’t fit for the MB2; the gear wheel is on the wrong side of the flywheel and the flywheel of the MB1 is bigger than the one of the MB2;
The protective cap of the MB1 for the magneto gear wheel is smaller than the one for the MB2;
The magneto of the MB1 sits lower on the engine housing and is smaller in size than the one of the MB2;
The brackets of the protective cap of the drive pulley lack on the MB1;
The MB1 has only half a protective cap relative to the MB2;
Motobecane used more than one kind of handlebars; a more bend one was manually made which allows you to sit up straight;
The drive pulley is replaced by a type used by the MB2.