(November 14, 2017) Just because you can do something doesn't mean you should do it, or that it's even OK to do it. In this category falls the deed of mounting an automobile tire on a motorcycle, front or rear.
I read Motorcycle Consumer News (MCN) religiously and every couple of years or so, someone writes in asking about the efficacy and safety of using a car tire on a motorcycle; and every time, the editor writes back that it's a very bad idea and explains why.
I had never actually seen it done until this year. Here (top right) is a picture I took of a Yahama cruiser in a small local shop. I did a double take on this and asked the owner about it. "No," he replied when I asked him about it, he didn't put that tire on the bike. My friend Mike and I looked at it and laughed.
I suspect some inexperienced riders do this because they have a tire that fits lying around and decide to use it on their bike. Or maybe they hope to get the mileage life on their bike that they would get on a car. Regardless, an experienced rider doesn't need an engineering or physics degree to understand why this approach is a really bad idea.
Motorcycles lean in turns and their tires have to be curved to accommodate lean. Click on the image to get a better look at this tire. How well do you think the rider can lean on this tire? What do you think will happen when he or she tries? You can be sure it won't go well.
Buy and mount only tires approved for your brand and year motorcycle. This will increase your odds of living longer.
Keep the shiny side up!
-The Long Rider