Have you ever looked at a new tire and wondered what those little rubber things sticking up are called and what they are for? These items are called tire hairs.

The little rubber hairs on the tires aren’t because the tire used to have actual hair or that its now experiencing baldness. These little items have been though to serve a purpose, but that purpose might not be what you expect it to be. Let’s explore what these items are and why the are part of a new set of tires.

Why do new tires appear to have rubber fur?

The small rubber items that stick up out of every new tire gives you that warm and fuzzy feeling that you’re truly getting a new item and not something that’s been ridden around on the road. It doesn’t take long before these small rubber items wear off and your tires look like every other tire you’ve ever seen. These items, plus the wonderful new tire smell (go ahead, inhale the chemicals) provide you with the secure knowledge that you’re buying new tires and not a retreaded or used set of rubber. However, these little rubber items have a real name and purpose.

What is the proper name for these rubber items?

The tire hairs, which is a relatively friendly, unassuming, and nonconfrontational name are actually called something that can be considered more insulting. These little items dare called “vent spews,” which is a strange official name for something that could have easily been made more friendly. These rubber items are also referred to as sprue nubs, tire nibs, gate marks, or nippers. These little items have a purpose, but before we got into that, we felt the name was important to cover. Still, we’re going to stick with tire hairs instead of vent spews for this item.

Why do tires have these little rubber nubs?

Before the markings and tread can be applied to a tire, it must first be a green tire. This means it’s a tire compound built into a shape but without the markings. The green tire is placed into a tire mold where all the markings can be applied. To create these markings and the tread, heat and pressure much be applied to the green tire. The rubber expands to fill the mold which allows the tire to take on the tread pattern and be stamped with the pertinent information.

Unfortunately, sometimes, air bubbles will form during the application of pressure and heat. These air bubbles could cause tires to be misshapen and deformed. To prevent this, a spew hole or vent sprue is used to relive that excess pressure and ensure the air has an escape. This ensure the rubber can expand and form the proper tire shape. When the air escapes, the tire manufacturer can ensure no air remains between the tire and the mold. As the air escapes into the spew hole, some of the rubber goes with it which creates the tire hairs.

For the most part, the little nippers on the tread face are shaved off, but the sidewalls and shoulders of the tire can still have these little items on them.

Should you remove these nippers from your tires?

There’s no practical purpose in removing them. Eventually, they will wear off and be unseen, but some people like to remove them, especially if they’re planning to show off their vehicle. The only functional purpose of these little rubber nibs is during the production process. They are a by product of this process and the result of the manufacturer ensuring a tire is properly molded.

If you want to remove these little items from your tires, it’s a good idea to do so with only your bare hands. They come off easily enough and using a sharp object to remove them puts your tire in danger of being punctures. In fact, removing the tire hairs with your hands can provide a bit of stress relief and allow you to feel a bit better afterward.

Why do some people shave their tires?

The manufacturer might shave the nippers from tires to allow the tread to look uniform and professional, but there’s another reason some people are shaving their tires. Many racers will shave the tires of their racing car to improve the grip. Taking of the top tread layers allows the car to grip better on dry pavement because the tires can heat up faster and become slicker. Of course, if you’re using your vehicle on public roads, you won’t want to shave the tires. The more tread you have on your street car, the better, but on the track, the slicker the tires, the more grip they can get. It sound a bit counterintuitive, but it really works.

What are feathered tires?

Feathered tires refers to the tread wearing more smoothly on one side of the tire than the other. This can be caused by several factors. The most common reason for a tire to become feathered is an improper alignment. If the wheel isn’t aligned right the tires will wear unevenly and cause problems during driving. Feathered tires will need to be replaced much sooner than tires that are aligned and wear evenly. Another cause of this problem are under and overinflated tires that don’t have an even tread contact with the road.

Why do some people put tires on the roof?

Tires are heavy, rubber, and often sit flat once on their sides. They make the perfect item to hold down a roof in an old trailer. Generally, you could see tires on the roofs in many trailers in your local trailer park. Residents in these areas have done this to prevent “roof rumble.” This is a phenomenon where the roof begins to make noise during wind storms. The tires hold the roof down and help prevent the wind from raising the metal up and away from the tires.

Now you know more odd facts about tires that you probably never thought you would. Next time you see the tire hairs on your new set of rubber, you’ll know they are called something else and understand why they are on your tires.