Richer would not release the terms of the deal.
"Honestly, it's always about the money, yes, but more importantly it's about something you truly believe in and truly use," Kid Rock said. "At least, people that like what I do and are into what I do understand that."
As a Harley owner, he said he has more authenticity than other celebrity hawkers.
"I would consider Peyton Manning and Shaquille O'Neal friends, but let's be honest, are they driving around in a Buick every day?" Kid Rock said. "I'm not so sure. I'd be surprised if they were."
Kid Rock's tour supporting "Rebel Soul," which was released in November, begins Saturday in Kansas City. It concludes Aug. 31 at Harley's 110th anniversary celebration in Milwaukee.
Another Harley fan and motorcycle owner is Wisconsin's Republican Gov. Scott Walker. Kid Rock, who campaigned for Republican Mitt Romney last year, said he followed Walker's successful push in 2011 to effectively end collective bargaining for most public workers.
"I hope the workers and people find this to be better in the long run and if it's not, I hope they change it back," he said. "Union working class people are a lot of people who look to me, so it's a tough thing to say that and go out and support it, but at the same time you have to take a stance and say what you think is right."