[MrAtom]

Originally Posted by Yarhj

The key thing here is the speed rating of the tires, rather than the overall quality. The faster you go, the hotter your tires get, and motorcycle tires are built to stand up to a certain maximum sustained temperature before the rubber starts to break down. Here's an explanation of speed ratings and here's a chart of the different speed ratings for motorcycle tires.

Part of the reason to have different speed ratings is that it's hard to make a tire that's both grippy AND resistant to high temperatures. It can certainly be done (see for instance the Bridgestones used in MotoGP for the last few years), but it's much easier to just make the tire out of a softer material to get more grip. Of course that softer material may melt and bubble at high temperatures, so you end up having to rate it for a lower continuous speed. Likewise, the cheapest way to make a tire stand up to higher speeds is to use harder rubber that may just not be very grippy. Hence you can have tires from two different manufacturers that are rated for identical speeds, but with widely differing levels of grip (and cost!).

Interesting. Thank you for an insightful post!