Mod syndrome is something that's unavoidable for most sportbike enthusiasts. We've all suffered from mod malady and sometimes it's absolutely impossible to cure, and can even get progressively worse. It's a curious situation: Spending money for shinier, faster bits can make us feel great, but sometimes those buys can backfire and really hurt.
A lot of mods aren't cheap, and we have to choose wisely when flipping through catalogs and browsing Web sites. Even on an imaginary shopping spree, the chances are pretty great that we'd make some poor decisions while selecting parts to make our bikes look better and go faster. This is why we wanted to find out through cold, hard numbers which of the most popular aftermarket mods had the biggest reward-both on paper as well as perceived.
With a stock 2009 Yamaha R1 as the platform we looked to Graves Motorsports for support and to help us record the results. The plan was simple: Take an average fast group rider, put him on a stock bike and add aftermarket parts one by one, all the while noting lap times and rider impressions. The results were interesting, and not exactly as we predicted.
WHAT ABOUT GEARING?
No, we didn't forget about one of the most valuable and cost effective mods for a sportbike, but the nature of Willow Springs Raceway didn't require any gearing adjustments. First and second gear aren't even used during a lap, and because of the high speed corners, lower gearing wouldn't have had an impact.
For street riding or slower tracks however, a smaller front sprocket or larger rear (or both) will drastically adjust the bike's power delivery and make it feel much quicker lower in the rev range.
Experiment on the street with aftermarket sprockets and you'll be pleasantly surprised. Just hang on tight.