Considering how thunderous the stock pipe was, I was worried the open-core exhaust was going to be deafening, but it’s no louder and netted a whopping 7.6-lb. weight savings. We took the bike back to the local Aprilia dealer to have the racing map in the ECU unlocked, and then went straight to the dyno. The extra fuel and freer-flowing pipe pushed peak power from 149 to 152.2 bhp and torque from 72.5 to 74.3 lb.-ft., while simultaneously smoothing and improving midrange performance. The downside is gas mileage dropped, from a distressing 26 mpg down to a downright disturbing 22 mpg in city riding. My nose tells me that the race map is rich, so hopefully fine-tuning the fueling with an aftermarket module will improve efficiency while getting closer to the Factory’s 155.4-bhp output. If not, a full race exhaust may be in order—though I shudder to think of the challenge installing V4 headers poses.