I've ridden a lot of "scary" (slow, ill handleing, brakes) motorcycles but never really been bored on one. The most unexciting one would have to be a BMW RT (cb750 right up there but with enough scary to not win). If ya want unexciting and scary; Honda cb350.
I've forgot more than you kids ever knew!
Retired and living off the interest on the money I owe.