Comanche
The Comanche U-550 "GI" is a 1944 American World War II motorcycle with a sidecar, sold in the store. It is a two-seater for you and a companion, with no mounted weapons.
A quick bike with room for one passenger in the sidecar. It plays much like the Baikal A-750 you can steal for free.
Buy it in the in-game store for 700 credits. It then appears in your list at vehicle pickup points.
It is a cosmetic choice more than an upgrade, so skip it unless you like the WWII styling.