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I've gone through this before.. ordered a set of 10 pound wheels which were 11+ pounds.

Also I'd bet money that 21 pound 15" steelies can out accelerate 20 pound 18" alloys. All else being equal. OD, tire weight, traction, etc. Just physics.. distance of mass from center of rotation.

update- I have access to a scale and a dr-33 17" wheel. I'll check when I get a chance.
 

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I've gone through this before.. ordered a set of 10 pound wheels which were 11+ pounds.

Also I'd bet money that 21 pound 15" steelies can out accelerate 20 pound 18" alloys. All else being equal. OD, tire weight, traction, etc. Just physics.. distance of mass from center of rotation.

update- I have access to a scale and a dr-33 17" wheel. I'll check when I get a chance.

Yup. I had a great demo tool for my HS Physics classes that showed this. Good intro to rotational dynamics: Two "wheels" of equal mass. One was made from solid wood, the other was a steel ring. Put them both on a ramp and let them go from the same height. The wooden one would win the race down the ramp, every time. The steel ring would roll out further though. Then spend the next 15 minutes figuring out why...


https://www.flinnsci.com/ring-and-discs---demonstration-kit/ap4634/
 

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Smash the center out of a automotive wheel with a sledgehammer and weigh the pieces, you would be surprised how little mass is there. Its all in the rim. Going to a larger wheel you are moving a lot of mass out. Just one of the many reasons I hate big wheels.
 

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Smash the center out of a automotive wheel with a sledgehammer and weigh the pieces, you would be surprised how little mass is there. Its all in the rim. Going to a larger wheel you are moving a lot of mass out. Just one of the many reasons I hate big wheels.
Agree completely, but pointing out the obvious is wasted effort. Trying to explain why the large diameter wheel/small cross-section tire a la the funkmasterflashfad is just beyond-fuckin-dumb for everyday driving on potholed streets just gets a blank stare and then, "But they look dope!"

jack vines
 

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Sometimes I wonder if something more nefarious is going on with this trend...

Cars are less profitable than SUV/CUV
Car makers prefer you to buy SUV/CUV
All modern cars now have low pro tires which are easily damaged on potholes.
You want tires with a reasonably tough sidewall? UP sell to SUV.

Take a look at any of the high hp 1/4, 1/2 or 1 mile racers. They put "small brake kits" on their modern cars so they can ditch the stock huge diameter tires in favor of more performance appropriate tire sizes... To those interested in performance the large wheels are a handicap.
 

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Agree completely, but pointing out the obvious is wasted effort. Trying to explain why the large diameter wheel/small cross-section tire a la the funkmasterflashfad is just beyond-fuckin-dumb for everyday driving on potholed streets just gets a blank stare and then, "But they look dope!"
I think this trend started originally because supercar makers started fitting very large brake systems on their cars that required larger wheels to clear them. Some people started thinking "big wheels = high performance" First aftermarket wheel makers started offering larger wheels and then automakers started making them standard or at least optional. The trend has grown and IMO gotten ridiculous.

Though in some cases carmakers are at least upgrading their brakes. I wanted to get some 15" wheels for my Mazda3 when I used to autocross it (it came with 17" wheels) and found that the ones I wanted would not clear the front brakes, apparently there are some 15" wheels that fit but most don't.
 

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Sometimes I wonder if something more nefarious is going on with this trend...
I don't know about big wheels being part of any conspiracy theory but I have long suspected the trend of tires that are narrower than the wheels they are fitted on were a way to sell expensive OEM replacements for easily curb damaged wheels.
 

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Why does the marketing want people to think this way? They want you to think affordable 15" tires are only for cheap crap cars why?

The same reason that the makers of Rogaine spend millions convincing men that the natural process of hair loss while aging is a BIG PROBLEM, and *ahem*, they have the solution...to make money on the poor saps that believe it.
 

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With a car like the Bolt, you can be rest assured that they already put a lot of engineering effort (with very expensive tools and measuring equipment) to make sure that the vehicle is designed with maximized efficiency and performance. I actually replaced my tires not very long ago (with a high quality performance tire) and was shocked at how much difference sticking to Low Rolling Resistance is KEY. I went from an average of 3.6 m/kwh to 2.7 m/kwh. I ended up returning and re-ordering new LRR tires. Back to 3.6 m/kwh. And DON'T sipe! The reason you are better off with greater range is you will be charging your vehicle less. Less charge cycles = longer life.
 

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With a car like the Bolt, you can be rest assured that they already put a lot of engineering effort (with very expensive tools and measuring equipment) to make sure that the vehicle is designed with maximized efficiency and performance. I actually replaced my tires not very long ago (with a high quality performance tire) and was shocked at how much difference sticking to Low Rolling Resistance is KEY. I went from an average of 3.6 m/kwh to 2.7 m/kwh. I ended up returning and re-ordering new LRR tires. Back to 3.6 m/kwh. And DON'T sipe! The reason you are better off with greater range is you will be charging your vehicle less. Less charge cycles = longer life.

Replying to old thread but in general, I think the big difference is going from very high performance tires to LRR tires, going from one extreme to another.

In my case I also ditched LRR tires simply because there were no LRR Summer Tires available from any brand when I bought my tires. Instead of going for the super performance tires I went for more middle of the road tires (almost(?) all summer tires are classified as performance tires anyways) with the Kumho Ecsta PS31 which obviously grip WAY better than the OEM tires (that's not saying much at all) and only give me about a 10% efficiency hit compared to the OEM tires. Now when the time comes to replace these (several years from now) I'm going to take another look for LRR summer tires but I'm not going back to "all season" tires in any case.
 
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