Tire Facts: Why are there small rubber hairs on new tyres? Know their real work?

Tire Facts: If you have ever looked carefully at the tire of a new car, bike or scooter, you must have seen small rubber hairs on it. Seeing these, a question arises in the minds of many people as to what use they are for. Some people believe that they increase tire grip, while others believe that they help reduce road noise. But the truth is different from this. Let us know why these rubber hairs appear on new tyres.

What are these rubber hairs called?
These small rubber hairs on the tire are called Vent Spews or Tire Nibs. These are also known as Sprue Nibs, Nippers or Gate Marks at some places. These only appear on new tires and as the tire wears, they wear away due to road contact and friction.

Why are these formed on tyres?
These rubber hairs are related to the process of making tyres. Vulcanization process is adopted while preparing tyres. In this, raw rubber is placed in a special mold and given high temperature and pressure, so that it completely takes the shape of the mold and a strong tire is prepared.

Very small vent holes are made in this mold, whose function is to release the air trapped inside. When the pressure increases, some of the melted rubber along with the air escapes out of these vent holes. Later this rubber cools down and takes the form of small rubber hairs.

Do these increase tire performance?
No. These rubber hairs have nothing to do with the tire’s grip, mileage, speed, braking or safety. These are simply part of the manufacturing process and do not play any additional role in the quality or performance of the tire.

What is their real job?
If air gets trapped inside the mold during tire manufacturing, air pockets or bubbles can form within the rubber. This may affect the strength of the tyre. Vent holes allow air to escape ensuring that the rubber is spread evenly throughout the mold and that the tire is finished without any imperfections.

This is why rubber hairs visible on a new tire are an indication that the tire has been prepared with the correct manufacturing process. However, after driving for some time, these rubber hairs normally wear out and disappear.