Two wheels of a different kind

One of my brothers lives about 3000 miles away, so we don’t get to see each other very often, but when we do we have some great times and some great stories to tell afterwards. This is one such story. It is, strictly speaking, a tale of two wheels; it’s just that the two wheels are the rollers on a belt sander rather than the wheels of a motorcycle.
The last time I visited, and after the requisite couple of beers to catch up, we ended up out in the garage (where else?). When I’d last been there it was little more than a shed that you could fit a car into, but since then he’d insulated, finished the inside, put in cabinets, lots of shelving, good lighting and so on including putting in a brand new garage door – which now displayed three large dents, in a roughly triangular shape, about 2 feet off the floor. Naturally I asked what happened.
“Well let me tell you about that, but first have another beer.” he said. “You ever listen to the CBC?”
“Of course.”
“Well one day they had on this program where this guy was talking about belt sander racing. I didn’t catch all of it ‘cause I was working on the truck at the time, but these guys would race belt sanders for fun.”
I’d heard of belt sander racing, but couldn’t quite figure where this was going.
“So I was out here one day and came across that 4-inch sander over there” he said. “Well it works pretty good, so I thought I’d give it a try. I cleared a path from here to the door, put on a course sanding belt,  duct-taped the trigger closed, sat on it, and plugged ‘er in.”
“You sat on it? You’re not supposed to ride the thing!”
“Yeah, so I found out. Keerist, did it ever take off! Damn good thing the cord was only 6 feet long because even after it pulled out of the wall I was still going like hell when I hit the garage door.”
Now I’m laughing. Hard. Beer coming out the nose hard.
“Yup. Those two lower dents are my knees. The top one is my forehead. And an $800 door too.
“Didn’t try that again.”