15. With everything installed, the Fat Boy was then put on the dyno for some f nal results. In stock trim, the Fat Boy managed 70.21 hp and 88.48 lb-ft of torque. Under the guidance of the SRTS, the bike now makes an absurd 141.52 hp and 138.13 lb-ft of torque. As you can see, the kit doubled the bike’s stock hp output and boosted torque by more than 55 percent! Sure it’s a pricey investment, but can you really put a price on the amount of fun you could have with this much power? Plus it’s important to keep in mind, with some internal engine mods, the results could be insane! And if you decided to sell the bike you could always pull the system off the bike and install it on another bike.