Valve train noise on a Harley is one of those things that riders either dismiss too quickly or panic about unnecessarily. The truth is somewhere in the middle — and knowing the difference between normal mechanical sound and something worth addressing can save you real money and a lot of unnecessary worry. Here's what's actually going on when your valve train is louder than it should be.

Here's how I read a dyno sheet, what I'm looking for, and what the numbers actually tell you about how a build is going to feel on the street.

I've been building Harley engines for over 30 years. And if there's one question I get more than any other, it's some version of this: "What cam should I get?"

I've spent the last several decades building engines, winning championships, and talking to riders about what actually makes a Harley perform. Most of what I've learned isn't written down anywhere. That changes now. Why We Built This Star Racing has been a parts business for a long time. We've shipped cams and other high-performance upgrades to customers across the country and around the world. We've built race engines that won six NHRA championships. We've helped thousands o