Ronin Motorworks, a new Colorado-based motorcycle manufacturer, has reengineered a firearms company’s design exercise and put it into production. The Ronin Motorworks Magpul Ronin 1125R (www.roninmotorworks.com) is based on a motorcycle prototype developed in 2010 by Colorado’s Magpul Industries, which makes rifle accessories. Like the prototype, the Magpul Ronin is built around the 1125R Buell engine and chassis. (Harley-Davidson’s discontinuation of the Buell brand in 2009 inspired the name Ronin, the Japanese word for a samurai who no longer has a master.) The bike’s 1125 cc V-twin produces 128 hp. The Ronin also features a car-type radiator at its front end and a 1950s-style linkage suspension system. Ronin Motorworks plans to build 47 examples, a reference to the 47 ronin of Japanese lore. The first few bikes will have a starting price of $38,000. Deliveries are set to begin this summer.