Factory Fatty Pipe. The Factory Fatty is reminiscent of the "works" or cone pipe once used by Factory Teams. It shares many of the same characteristics with its craftsmanship and material quality. Thoroughly tested and developed by the best racers in the sport, this pipe delivers true "works" style technology to the public. Looking to turn your bike into a race-ready powerhouse? The Factory Fatty is the first step you should take for bolt-on performance. Works performance meets superior style. Offers increased torque and throttle control. Used by record breaking madman Robbie Maddison and the FMF Factory off-road team. Supplied O-rings ensure a flawless fit. Quality construction for maximum durability. Unplated 20-gauge header and 19-gauge body for that "Factory" look. The perfect modification to any 2-stroke race bike.