Motorcycle Safety & Driveability: cycle tires, rear tires, concrete answer


Question
This may seem silly but I'm blonde so here goes.. Can I put a front tire on the rear of my bike?  It clearly indicates front on the tire but can you tell my why I wouldnt want to put it on the back or the danger/outcome?  
Thanks for your time.
angela chapman

Answer
Not a dumb question at all. I only wish I had a concrete answer for you!

While they may look similar, front and rear tires are presumably designed for different functions, and so in theory a front should not be used on a rear, and vice versa.

The front tire's job is turning and braking. A rear tire's job is accellerating, leaning, and braking. The different forces applied to a tire, in this case you're talking about mostly cornering and braking on the front, and mostly accellerating on the rear, require different construction of the tires.

But there are lots of things that make perfect sense in theory that are not necessarily important in reality. Let me give you a hypothetical example.

If I had a bike that needed a new rear tire badly, and I didn't have any money, and someone gave me a front tire that was the appropriate size to replace my rear, I'd probably use it--a good tire with an F on it is probably safer than a bald tire with an R on it.

Ideally, you'd want to have a proper new rear tire, but sometimes you have to compromise. If you're not going to be using it for racing or riding at the absolute limit of your tire's traction, it's not likely that you'll run into too much trouble.

Lots of people fudge on their tires all the time. Some people have problems with it and crash, others don't. It's up to you to decide what's safe, what amount of risk you can live with, and decide whether to use a questionable tire or not.

Pat