Tire wear and speed along curves


#1

Do tires last longer if you drive at the speed limit, particularly around curves? Asking as I have found you can do say 50-60 on curves stating 40-45 limit with no problem. But does that stress tires/wear tires more than going at limit?

Or is that likely more a problem on tighter curves 35 and below, when you’re going faster than the limit (which I rarely do).


#2

I have found that the faster you drive, the faster your tires wear period. Even when tires aren’t skidding, they have a slip angle while cornering and the more g forces needed to corner, the higher the slip angle.
My opinion is based mostly on my experience riding large powerful and small motorcycles. I went from a Kawasaki ZRX1200R, a bike with over 100 horsepower, to a small Kawasaki Ninja 300 with barely more than 30 horsepower. Why? Because I came to realize that I needed to get 70+ mpg a whole lot worse than I needed to double the speed limit.
Because this bike is so small, I like to stay under 60 mph and I choose routes that have low speed limits just so I don’t have to flog that tiny engine.
I fully expected to get amazing gas mileage by doing this, but just how long tires last when you ride this way was a real eye opener for me.


#3

BLE: what kind of eye-opener?

The sharper the curve, the higher the speed, the more the tires wear.


#4

CapriRacer, our resident tire expert, has notes several times that tire wear considerably more on turns than going straight. Here’s one of his quotes from earlier this year:

However, tire dealers have insisted that tires have some sort of mileage warranty so they have some way to compare and contrast. If you do a comparison of the warranties vs the UTQG treadwear rating, you'll see a loose correlation. But treadwear warranties also do not work in a straightforward manner.

That’s because most tire wear occurs in the cornering mode. In order to generate the force necessary to move 2 tons of vehicle in a different direction, the tires have to produce a slip angle - the difference between the direction the tire is pointed and the direction it is actually going. And that scrubs off rubber - the more severe the cornering, the more rubber is scrubbed off. When doing severe handling maneuvers, tires last 10’s of miles.

On the other hand, a tire that goes straight ahead, is close to no wear at all! I’ve conducted tests where the range of mileage received was a 10 fold difference - 10K to 100K - and the differences were the road surface (new abrasive concrete vs well worn asphalt) and the service (local delivery vs hauls between cities.)


#5

Couldn’t have said it better myself! Oh, wait …


#6

Going around curves fast scrubs the rubber off. It’s that simple. An extreme example is race courses, where the rubber from the tires actually forms little rubber “marbles” on the curves.

Rather than suggest going the speed limit, however, I’d suggest going with the flow of traffic. Trying to go the speed limit on many of the roads in my area will cause accidents. That discussion by itself have caused long threads on this forum.


#7

Of course tires wear faster when you round a curve faster. The mileage life given on a new tire is measured on a roller with no turning. So a 60,000 mile rated tire in real life won’t last as long. I have Michelin X tires rated at about 90,000 miles or so and will be happy to get 70,000 miles out of them in normal driving.

Turning the steering wheel with the car stationary will also wear your tires out fast.

Proper inflation is perhaps the most control you have over tire life.


#8

I have no idea what state OP is in and state traffic laws can vary. In my state the number displayed beneath the curve signs are advisory not regulatory. Curves wear tires significantly more than straight roads.


#9

In my youth we had a saying:
“if your tires aren’t wearing out on the edges first, you’re not cornering fast enough.” :smile:


#10

Good ol’ bias ply tires rolled over in the corners - squeal city!


#11

True.
And when I watch my old TV shows I get a kick out of the body roll. It’s a riot to watch. But hey, my '64 Fairlane really DID roll! Although in truth the TV producers used to remove the shocks to get an exaggerated effect.


#12
BillRussell BLE: what kind of eye-opener?

The sharper the curve, the higher the speed, the more the tires wear.

The “eye opener” was how fast high cruising speeds makes motorcycle tires wear. Straight line, as in doing 80 in the left lane of the freeway verses keeping it down to 55 or 60 on the back roads, even with their curves.
I still corner fairly aggressively on my bike, it seems to make the edge wear keep up with the center wear and the rear tire doesn’t get that “flat spot” in the center of the tread.
Motorcycles used for long distance touring are notorious for flat spotting the center of the tread on the rear tire. It tends to make for heavy steering, although, you don’t really notice it until you put a new rear tire on, now suddenly you have an unworn tire and the handling difference is like night and day.

Think about it, if it takes about 35 horsepower at the rear wheel to make a small motorcycle go 100 mph, how much linear force is the engine fighting from air resistance.
We go to the linear (drawbar) horsepower formula.
HP = pounds of force X feet per second / 550
100 mph = 146.7 feet per second.

Solving for pounds of force we get 131 pounds of force. In other words if you were towing the bike at that speed with a water ski rope hitched to a pickup truck, the rope would have a tension of 131 pounds. This is the tractive effort the rear tire must apply to the motorcycle continuously.
This causes something very similar to slip angle, it’s a slip speed. The bike is actually going a fraction of a percent slower than the theoretical speed due to tire rpm.
Now if you cut that speed in half, the air resistance is only a quarter as much and the tire is under much less stress.


#13

Ther’s an old black & white movie with Robert Mitchum called “The Man Who Cheated Himself”. It has a car chase scene with one of those Nash bathtub cars in it making a sharp turn. It nearly rolls over on its soft suspension and squealing undersize tires.


#14

Speaking of the TV shows, I’m still wondering how tires squeal on gravel or dirt roads?


#15

Not to mention how every crash short of a fender bender results in the car exploding in a huge ball of fire.


#16

Then there’s the Simpsons episode where an Amish buggy goes over a cliff and bursts into flames.


#17

Sound effects, Bing, sound effects.
Yup, I know the post was toung-in-cheek. :smiley:


#18

Going faster around the clover leaf to get on the freeway versus pushing the engine harder on the straight – I’ll go with the extra tire wear. Engines are $$$$$ Tires are relatively cheap


#19

Bing: “Speaking of the TV shows, I’m still wondering how tires squeal on gravel or dirt roads?” Are you referencing “The Pukes of Buzzard”? LOL


#20

I always thought that show was funny

I seem to recall Roscoe often crashed his cruiser and the fenders would fall off. Was it some kind of Mopar . . . ?

Sure was convenient, all those ramps set up, so that the Dukes could “fly” over obstacles and land, basically destroy the car, but the viewer never saw the General Lee all busted up. I heard they went through a LOT of General Lees during that show