Bottpower’s Carbona kit takes the XSR900 from retro throwback to space-age racer without any frame modifications. (Aaron Richardson/)The Yard Built kit apes the specials that Bottpower built to dominate the 2017 Pikes Peak International Hill Climb. (Aaron Richardson/)The XR9 Carbona takes cues from the Yamaha R1 and R6, working in the sportbikes’ round LED marker lights and a number plate…

The bodywork relies on 3-D printing, and sneaks in design elements from the YZF-R6 and YZF-R1, namely the miniature round headlights, to give the XSR a more modern, race-bred look. The kit includes a new fuel tank cover with molded-in air intakes; a carbon fiber seat and tailsection with a saddle trimmed in Alcantara; new taillights, turn signals, headlights, and…