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Tire Siping

During a recent visit to a local tire retailer I was intrigued by a process called tire “siping”. This involves slicing about one thousand horizontal razor-thin slits in each tire. This supposedly is beneficial for improved braking distance in snow and rain, up to thirty percent longer tread life (because the tire stays cooler), and better overall handling. I’m somewhat skeptical that there are some disadvantages to this perfect process. My unscientific theory is that it may create more rolling resistance, hence reduced gas mileage and more road noise. I’m willing to hear some scientific pros and cons.

Thanks…Ron

Completely unnecessary and possibly compromises the structure of the tire. Tire manufacturer’s spent tons of money and research on tread designs to try and get an advantage on the competition. And this local dealer is promising to improve on that with some trim-trim, slice-slice? This is just a profit gimmick for that retailer, nothing more. I can guarantee that the tire warranty will be negated with such tampering.

I’ve seen tire siping used to provide a custom tread design for show cars. Other than that, there’s no advantage.

I agree w/BK, this has been around for many years, has always been unneeded. I have much more faith in the tire experts at Michelin, Goodyear, etc, than Joe Blow at the tire store. If this simple procedure was a good idea, the manufacturers would do it.

New tires are siped in the design.

It is a profit maker for a tire store, nothing else.

By making the tread more flexible, it will wear much faster as it squirms on the pavement. Handling is degraded because of the tread flexing…

Look at two identical tires, one half used and one shelf new.

  • virtually every tire in my inventory has this feature , I just looked at a Goodyear wrangler at/s and a General grabber hts -

The new tires have those slits in the tread surface.
But they do not reach very far down. They’ll disappear at less than 1/4 wear.

I suppose if you notice a difference in the handling as your tires wear, you could elect to have more cut in. But there must be a good reason that none of the tires have them the full depth. I’d immagine it has to do with the strength of the tire surface flexing that close to the inner plies.

For wet smooth surfaces and ice they grab better. But they wouldn’t allow for much flexation without splitting.
( Wet surface factory and boat shoes have those mini slits for traction )

I did notice that some winter tires came with similar pre-siped treads but were more visible and were in a zig-zag configuration. I’d hate to ruin a brand new set of Continentals that cost close to 600 dollars.

If your tires have few sipes in them and you get lousy traction in rain, you might try getting some sipes cut into them. You won’t get longer tread life or cooler tires but traction is always welcome.

Let’s go through the claims:

…beneficial for improved braking distance in snow and rain: Yup, that’s true.

…up to thirty percent longer tread life (because the tire stays cooler): Absolutely untrue!! Not only doesn’t the tire run cooler, the tread wear is more rapid because of the movement of the smaller tread pieces.

…and better overall handling: only true if you only count the traction improvement in snow and rain, but otherwise, No!

…it may create more rolling resistance, hence reduced gas mileage: Yes,

…and more road noise: Also true!

You kinda have to ask yourself: If this was such a good idea, why don’t the tire manufacturers do this in their factories?

Siped tires main benefit is traction in snow. That is why new dedicated snow tires are highly siped. So if you need a snow tire just buy one already siped by the manufacture.

It is old technology. The new technology (Winter not snow tyres) beats sipping in every way.

I have a ‘04 Infiniti G35 Coupe with 18’ wheels. No winter tires are available, without buying separate set wheels and tires for $1200+. My performance styled Toyo all-season tires are a joke in the snow. So what if I had them siped?