- Big tires


#1

New cars seem to be coming with very large tires, which I do no care for. They seem to be a very expensive option that are not necessary. Are there any advantages to large (over 15” wheels) to 14” & 15” wheels that would make them a good buy and not just a image enhancement?


#2

I don’t either. Whenever I’ve gotten used cars, I look up what the smallest size wheel is and make sure that that’s what I put on them. The larger wheels call for low profile tires which don’t last as long and give a harsher ride (granted they generally corner better). Other disadvantage to low profile tires is that you can damage the wheel itself if you hit a pot hole too hard. They do like nice, but that’s about the biggest advantage to them in my opinion


#3

The main advantage is they make room for much bigger brakes than can be installed inside a 14 inch or 15 inch wheel. The larger brake allows much higher heat capacity - brakes make heat - so brakes don’t fade coming down a long grade to braking many times on a very curvy road.

Not sure you shopped for tires lately but it is getting harder to find 14 and 15 inch tires anymore. Even 16 inch has dwindled quite a bit.

What goes around… very early cars, 1910’s 1920’s or 1930’s commonly had 24, 28 ,32 or even 38 inch tires.


#4

Our Volvo V70 has 18 inch wheels and series 45 tires ( Pirelli P6 ) with the sport suspension and we find it rides just fine and have done extensive traveling.


#5

If the actual tire diameter is larger, that makes the tire shape better match the road surface; i.e. a bigger circle is ‘more flat’ (not as sharply curved) as a smaller circle. So that could make the ride of a bigger tire smoother. Mountain bikes switched to 29 " from 26 " in part for this reason. Easier for the rider to deal with the bumps on a rocky path. The tire diameter can’t be increased indefinitely, as it would make the bike stand too tall. But many mountain bike riders say they prefer the 29 inch wheels.


#6

Yep, pretty much unavoidable now. Just make sure you get the smallest wheels for a given model. Base might be, say, 18”, with 19” or 20” optional.


#7

looked at friends 2010 maxima with stock 18" rims. he has over 1" clearance from caliper to rim. maybe 1.25" his rotors are not that big


#8

The wheels are getting bigger, the overall diameter of the tires isn’t changing much though. For example, a Camry from 2005 might have 215/65/R15 tires which are 25.5 inches tall. a new 2018 Camry might have 235/45/R18 tires which are 26.3 inches tall and little more than an inch wide. The biggest difference is size of the wheel, which is 3 inches larger, the tire itself is bigger, but not immensely so.

The thing is they are necessary. The reason being that the safety standards get progressively stricter and to meet them cars are getting progressively heavier (this also flies in the face of CAFE standards, but that’s another discussion). A heavier car needs bigger brakes, and bigger brakes need bigger wheels in order to accommodate them. My car for example has 15 inch rotors on the front wheels, this necessitates a 19 inch wheel at the minimum.


#9

Yep. We just bought a 90’s car for our niece. We put new tires on it. We paid less for all 4 tires plus road hazard warranty than I’d pay for 2 tires on my car.

But its brakes are tiny in comparison to mine. No way I’d get its little 15 inch wheels over my rotors. And I wouldn’t want to decrease my braking ability just to save money on tires. That could get expensive and deadly real fast.


#10

The granddaddy of huge wheels was the 1910-1912 Oldsmobile Limited, which had 42 inch wheels!
These cars–and their tires–were so huge that an additional running board was necessary in order to get into the car.


#11

And it didn’t even have front brakes. :wink:


#12

+1
Additionally, larger wheels and tires will not be affected as much by large potholes. A pothole that could swallow a smaller tire can frequently be driven over with a larger tire and wheel, with just a minor impact, rather than the kaboom that would result when a smaller tire/wheel falls into that pothole.


#13

Users of these need to be told:


#14

I have to disagree. A pothole will kaboom on a low profile tire and can destroy an aluminum rim. I see broken 20” and above rims all the time.

Larger rims with low profile tires handle better but ride worse than a smaller rim with a taller sidewall.

I think they made the rims bigger for style, more than anything else.


#15

I’m not sure cars of today are heavier than they were when 15” tires were the norm. I’d say the opposite would be true in a lot of instances.


#16

50 series seem to do ok with potholes, but when you get to 40 and below rim damage is a real problem


#17

If they’re required to clear larger brake components, that’s cool. I think the main purpose is styling, though. The higher trim levels get the larger rims. Not my cup of tea, really. A 4wd truck looks (and rides) better to me with a little more sidewall than a 20” rim can provide. But most people like ‘em. “Ooh, look at dem rimsss!”


#18

My current car came with 45-series tires, which made me kind of nervous, but so far they’ve survived maybe a dozen serious pothole strikes. I wouldn’t want to go any lower, though.


#19

Let’s compare

2001 Toyota Camry V6 - 3424 pounds

2018 Camry V6 - 3665 pounds

2000 Honda Civic - 2385 pounds

2016 Honda Civic - 2920 pounds

2000 Ford Taurus - 3415


2010 Ford Taurus - 4068 pounds

2001 Toyota Highlander - 3988 pounds


2017 Toyota Highlander - 4560 pounds

2002 Chevy Silverado - 5000 pounds


2015 Chevy Silverado - 5658 pounds

2002 Ford Mustang GT -3495 pounds


2015 Ford Mustang GT -3850 pounds

As you can see, across the board, cars have been getting heavier and heavier over the past two decades. Industry wide cars were at their lightest during the 80’s, before that they were heavier and since then they have gotten heavier as well.


#20

You’ve done your research. I can admit when I’m wrong, and I appear to be.

It’s hard to believe considering the thickness the body panels seem to have lost.