On our scale the stock pipe weighed 8.4 pounds. By comparison, the Yoshimura system weighed just 5.3 pounds. That’s a 3-pound savings, just like Yosh claims. On the dyno the bike’s peak output jumped from a pavement-rippling 8.69 horsepower to 9.14. That’s an increase of 0.45 horsepower, which doesn’t sound like much, but equates to a hair over a 5 percent increase. If your 100-horsepower bike gained 5 horses with a 30-minute bolt-on (and no fueling changes), you’d be pretty stoked, right? Besides bumping peak figures, the RS-2 adds thrust across the rev range.