Let's cut to the chase: I owe you a dyno run. I've thrown out various numbers regarding the Bonneville's output, all because I neglected to get a baseline when the bike was stock. I already knew that I felt an improvement with the Triumph accessory Arrow 2-into-2 exhaust and downloadable map, and while the quiet inserts do a great job keeping the noise respectable, with the inserts removed the pipes sound healthier and the bike seems to come alive. That observation prompted me to finally put the Bonnie on a dyno, and while we don't yet know where the bike stands compared to stock, we do know there's a noticeable difference between inserts-in and inserts-out. Should your inserts mysteriously disappear, you'll be rewarded with substantial power gains from 2500-4000 rpm and above 6000 rpm.