Full sus mtbs are good as you can bounce on the seat as you ride. I do it on my Santa Cruz nomad with 2 gel covers over the seat wearing tracky bottoms or lycra. The rear shock bounce and the squidgy gel seat makes me nut in no time
What makes guys and twinks cum when they are out cycling ? It can only be the pressure of the saddle on the balls which gives them randy thoughts and makes them shoot jizz.