Tires impact speed


We just bought new tires, Michelin Pilot Sport AS Plus, to replace Dunlop Sport 9000’s on 1999 BMW 540i. My wife claims the car is not as fast. I can’t tell the difference. In normal around town and highway driving, is it possible that she is right and can tell the difference in tire performance?

Not as fast? From a start? I can’t imagine any difference from tires. Around a curve? She must be driving FAST! Maybe they’re quieter, so it doesn’t sound as ‘fast’.

You might want to check the air in the tires yourself. Use the pressure listed in the owners manual or the placard on the vehicle. Low tire pressure can make the vehicle “feel” slower.

Perhaps your wife means the tires are not as responsive as the old ones. Since the new tires have more tread, they will seem less responsive than the old tires. Tire Rack has an article about breaking in new tires.

Ed B.

The new tires are probably quieter, which makes the car “seem” slower. I can’t imagine tires alone would make enough of a performace difference to feel in everyday driving.

It’s subjective.

If, on the other hand, your wife is a professional race car driver, maybe she can tell the difference.

On a less powerful car tires with more rolling resistance (aggressive tread) can affect rolling resistance enough to affect acceleration, I’ve personally felt this. But if she can feel a difference in a 540i she must be driving really aggressively.

Unless the others are right and I’m misunderstanding what she’s saying.

thanks, appreciate your response

Thanks, will check tire pressure. Appreciate your response.

thanks for your response and link.

She is not a professional race car driver. Thanks for your response

You have correct understanding of her view. Thanks for your response.

The Sport 9000’s are Maximum performance summer tires. The difference is readily apparent between decent summer tires and your new all-season albeit high performance tires if you push them.

The best ultra high performance all-seasons still cannot perform better on dry than majority of summer tires.

A heavier car like a 540i it likely apparent.

Alternatively confirm tire pressure.

New tires will make a car seem different sometimes. It may seem normal after a week or two. An alignment can make a big difference too.

When a high-performance tire like the Dunlops wear down to minimum tread depth, they are at their best, their most responsive handling on dry pavement…

The new all-seasons will seem mushy by comparison. She will get used to them and they will improve as they wear…

Like those old Bridgestone tire commercials where they showed how good their tires were even when they were worn by shaving off half the tread…just like racers do.

Is the outer circumference exactly the same as the old tires? You didn’t put on different sized tires, right? The new ones probably have a slightly larger circumference due to wear on the old ones but I can’t imagine this could be felt while driving it.

[i]Maybe the issue isn’t the tires.[/i]

It might just be a coincidence that your wife noticed this after you bought new tires, and you might not notice what she is talking about maybe because you are assuming it must have something to do with the tires.