How does your motorcycle exhaust system help your engine make more power, be more efficient, and sound amazing? Like many parts of the motorcycle, there are near-infinite variations. For exhaust systems Technical Editor Kevin Cameron and Editor-in-Chief Mark Hoyer discuss: length and diameter of the tubing, collector size and shape, how long each element of the system is, overall length, silencer type, cam design, port length and shape, cylinder grouping, and so much more. We get into four-into-one vs. four-two-one, the "power bulge," what is reversion, stepped headers and, well, like we said, so much more. Join us!