The small, spiky hairs you see on motorcycle tires are actually a by-product of how tires are made. These little spikes, known as “vent spews,” don’t have any impact on how the tire works.

While “vent spews” might sound like an odd name, it’s just one of the many terms used for these tiny fibers. Other names include sprue nubs, tire nibs, gate markings, and nippers.

But why do these hairs exist in the first place? To answer that, you need to understand a bit about how tires are made.

Tires start off as what’s called a “green tire.” This is just a tire-shaped rubber compound that hasn’t yet been marked with any information or had its tread pattern formed.

The green tire is placed into a mold, where heat and pressure are applied. As the rubber heats up, it expands to fill the mold, creating the tread pattern and imprinting the brand name, like Toyo Tires Proxes or Open Country.