The compensator is one of the most overlooked components on your Harley — and on M8 engines, one of the most dangerous to ignore. And the crazy thing is – most riders never think once (much less twice) about their compensator.

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 of street riders...