With half-a-million bikes in the area, there are bound to be some breakdowns.
If you're lucky, it's a simple fix like replacing a tire. But if not, yours could be a short rally.
Mechanics at Black Hills Harley-Davidson see between 1,000 and 2,000 repairs during Rally Week every year.
Most are fairly minor, but some require specific parts that have to be custom-ordered.
That can put bikers out of commission for a few days -- or longer.
"We've shipped bikes home, they've had friends pick them up," said service manager Jeff Ulvestad. "I've had one guy actually flew back in and rode his bike home because he was bound and determined to ride it home."
If that kind of delay does happen, even if it's just a day or two, it can be hard to find a rental.
One lucky rider, Jack Young of Iowa City, Iowa, whose bike was out of commission for two days actually did find occasional rentals, which let him tour the Hills for his first time with friends who had done it before.
"'Oh, we got to--' 'Oh yeah, I remember we did that so-and-so,'" he recalled them saying, "and I'd say 'Yeah, I want to go, too, you know.' But, so I say, I'm blessed" to have gotten a rental.
Had he not been able to get those periodic rentals, Young said his response to breaking down would not have been appropriate in polite company.