I hate cups. The dont protect anything, the just transfer the blow to the whole area around our crotch. I got yelled at all the time in karate for "forgetting" mine. I'll take the straight shot to the nuts, thankouverymuch.
Needing one while on a bike of anyvariety? Youve got one heck of a hardtail motorcycle, dude.
And its never my nuts that hurt at the end of a ride, so a pad there doesnt really matter.