Much of the criticism levelled at this new generation of custom bikes concerns usability. Whether it be fenders, suspension travel or comfort, the main undercurrent to the comments is that the bikes just aren’t functional in the real world. But if there’s anyone who really cares about how their equipment works, it’s a soldier. Hammered with rules about unwavering trust from day one, most soldier’s tools are nothing but thoroughly, brutally, unforgivingly functional. So what happens when a career warrior builds a custom bike? This happens. Meet Piotr and his newly weaponised Yamaha XJ750 Seca.