MC Rider in #47 touches on something (a sore point? Sorry, couldn't resist..) of 90% of all the replacement 4x1 pipes: ground clearance. It was TERRIBLE on almost all; if they didn't scrape/flatten on a good bump, they scraped all the way through a corner you could've ridden through with the stock pipes. And then, there's the Bassani 4x1. Minimal loss of ground clearance but the only way you scraped the muffler was crashing the CB.