When I rode a motorcycle, when I lived in Detroit, I'd be fine driving around the streets. But get on the freeway, I'd be freaked out by a) the speed, thinking that any little mistake = death, and b) other drivers.
I still don't like driving even a car on freeways in urban areas. There are tons of people, whipping in and out of lanes with inches to spare, driving a couple feet behind the vehicle in front of them, slowing down or speeding up for no discernable reason.
I dread going downstate, where, unfortunately most of my family lives, so have to now & then. The only upside to going there is White Castle.