Turn the key to unlock the Aprilia RSV4's seat and the tiny sliver of black plastic and the little butt pad pop off. On its underside is a clip holding an 8mm allen key; there's no room to store anything else, not even a pack of cigarettes. Store the seat cover somewhere safe and swap it out for the pillion pad. It mounts inside the same lilliputian space as the cover, but lifts the pad clear of the tailpiece's integrated fins, wrapping over them on the sides, front and rear to provide what's actually near-reasonable accommodation for the human posterior. A molded plastic handle points rearwards, clearing the taillight and providing a handhold, there's also a strap that runs across the front of seat between it and the rider's bum. The best approach to riding pillion on the RSV4 is to hang on to the rear handle with one hand and place another around the rider and on the tank. This will keep your weight forward, bracing you in two places against the strongest force the bike is able to exert -- braking. In that position, you'll be effectively braced to withstand the acceleration through your feet and by wrapping your forward arm around the rider's stomach. Hold on tight, while it's possible to ride on the back of an RSV4, the intelligence of deciding to become a passenger on a 180bhp, 184kg missile is highly questionable.