Have you ever taken a good look at your car’s tires and wondered what each part is for?
Yes, yes, we know that the tire’s treads are to keep it grippy on the particular surfaces you drive on, and we’re pretty familiar with the little tips and tricks to measure when they’ve become too worn to be safe.
And the drivers among us are familiar with the tiny valves that we have to locate, sometimes in the dark and cold, to re-inflate a flat tire.
But how about those tiny rubber bits that stick off of your tire? Some people think they look like hairs, others think they look like spikes. But are they supposed to be there or are they just a byproduct of the manufacturing process?
Should these weird little rubber bits actually be on our tires?
Well the truth is, those little rubber bits are supposed to be there. But they’re not for any purpose that you might expect.
Nope, these little rubber bits are known as ‘vent spews’ and are an important part of the tire manufacturing process.
That brand new tire you just got fitted to your truck? Just like all the others it was made by forming rubber in a mold. This mold is how the rubber gets its treat pattern, and forms the specific shape and dimensions of your particular tire.
However, due to the heat and pressure that is necessary to mold rubber into a well-shaped tire, air bubbles commonly form between the mold and the newly-forming tire. This is a problem because, if the tire doesn’t fill the mold fully and properly, some of the shape or tread pattern may not form fully.
This could impact the safety and efficiency of the tire, and the vehicle it was fitted onto.
The solution? Spew holes. These little tubes in the mold allow the excess pressure to escape, so that the tire fills the mold fully and properly, as Steve Burke – technical manager of Toyo Tires – explains:
“Air escapes, ensuring no air bubbles between tyre and mould, and takes with it little bits of the rubber. This is how vent spews are made. The spews on the tread face are mostly shaved off, but on the shoulders and sidewall of the tyre, spews remain intact.”
So there were once vent spews on the driving surface of your tire too, but these are shaved off during the manufacturing process. Due to their lack of impact on the safety of the tire, the ones on the sides of the tire are left intact.
Some people don’t care about these little bits of rubber, while others find them unappealing and bothersome. But if they were integral to the manufacturing process, would it ruin your tire to remove them?
Well no, usually not – though the manner in which you remove them is important, as Burke goes on to explain:
“It really doesn’t matter. Vent spews have no functional purpose post-manufacturing. Many show car owners take great pride in shaving or clipping the nibs down.
There is no practical reason to remove them, but if you must, avoid scissors and blades and just grab them with your hand and pull them off. It’s actually pretty good stress relief.”
So if you find them ugly, feel free to remove them.
But otherwise, it is completely safe to leave these little bits of rubber on your tire too.
If you thought that was interesting, you might like to read about a quantum computer simulation that has “reversed time” and physics may never be the same.