Front vs Rear tires - Differences?

[D. P. Larmee]

I am looking for new rear tire for the special and have come across a few good deals on tires in 130/90-16 size but sold as front tires. Are front and rear tires substantially different, or should these work perfectly well on the rear also? If there is a big difference, is there a good way to tell which one is which?

[NemisusDM]

Hey D. P.,
Here's a link to the ama tire info page...Just one note rear tires are made for accelerating and front for stopping.

http://www.amadirectlink.com/roadrid...resc/tires.asp

[Jerry]

Difference, as I understand it, is on two areas: load capacity and compound.

Load capacity is easy to spot; a max load capacity is usually cast onto the tire, such as 690 pounds at 40 psi. Given that most of the bike's loaded weight is on the rear tire they tend to have a much higher capacity than front tires, often by 100 pounds or more.

Second issue, compund, is harder to research. However, rear tires are almost always a different compound (mix of rubber and chemicals) than front due to the differet tasks each is designed to perform. Front tires need to stop, as weight transfer means the front tire provides more than 50 percent of your stopping power. Rear tires are designed to accelerate. Both tires must corner, of course, but the front generally has to do it with a narrower contact patch, so sidewall compounds are also different.

I suspect that putting a front tire on the rear would result in some differences in handling, probably not for the better, and lower over-all tread life.

Gven the (generally) lower load capacity and differences in tire functions I would not put a tire designed as a front time on the back of my XJ.

[D. P. Larmee]

That's about what I figured; I just wasn't sure. I guess I always assumed that the sizes for fronts and rears were different so that there wouldn't be any confusion. If you come across a used tire without a label on it, is there a way to tell whether it is a front or a rear? Maybe a number or letter designation that specifies it as such.

[psycoreefer]

I think its usually cast in the side of the tire whether its front or rear, but it may be marked differently by different tire manufactures. When I was looking for tires I found some that are marked for "both" front or rear applications. I'm not sure how they handled the different compounds and design in that case but I'd bet they wouldn't be as good as a tire designed to meet only one of those applications.