There are three typical configurations: motorized bicycle with sidecar; two wheels in the rear, one in the front (aka trike); and two in front, one in the rear (aka reverse trike).
One of the most successful trikes of its day was the De Dion-Bouton tricycle; from 1897 until the start of the 20th century about 15,000 licensed copies were sold, with De Dion Bouton usually supplying the engines, and it was overall the most popular motor vehicle in Europe.
[1][2] Trikes have caused tautological confusion and simply defied typical two and four-wheel classifications, especially in the 21st century.
[further explanation needed] There is another arrangement of three-wheel, with the wheels in a line; this is so far pretty rare.
[38] In one case the use of flexible type sidecars allow the center-line motor bicycle wheels to stay on the ground, and providing adequate handling[38] Motor bicycle related: