aluminum alloy wheels and tire "life"

[Tmoose]

I was thinking about the curious things that sales people have said to me and folks I know over the years.
I remembered an amiable VW sales guy assuring me the alloy wheels on a brand new 1984 GTI conduct heat away from the tires and make them "last longer." For a minute I guess I can picture the rotation centrifugally stratifying the dense cold air out toward the tire tread, but then I wonder about continual pumping action of the spinning sidewalls enforcing a toroidal flow pattern like a Tesla turbine and then I realize I don't know what I'm talking about and suspect the same might have been true of the salesman.

I don't recall hearing that theory ever again.

 

[patprimmer]

I would think that allow wheels could conduct heat from the brakes into the air inside the tyre better.

Regards
Pat
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[CapriRacer]

Let's see if I can add to the things salesmen have said in order to make a sale - and I'll confine this to absolute falsehood and it has to involve tires:

1) Nitrogen doesn't expand due to heat - unlike "air".
2) The belts in tires "slip" and that causes tread separations.
3) "Cupping" wear in tires is always caused by bad shocks or an out of balance assembly.
4) A "plug" is as good a tire repair as a plug/patch combination.
5) "Plugs" never fail if properly installed.
6) "Plugs" never cause tire failures.
7) Michelin tires never fail.


OK, that's enough for now.

 

[cibachrome]

Recaps are just as good as them OEM tars.

Super Mongo Sport-Flexs are just as good as them there Goodyeers.

Don't never need 5 bolts on there save wait by only having 3

Bald tires get better fool economy.

buy 3 get one free.

tire disposal fee.

need new tpms stems when rotating tires.

blems are easy to balance with 34 oz. weights.

bent rims are made that way intentional.

wheel offset don't meam nuthin' as long as they bolt on.

runflats never wear out.

runflats never need air.

racing radial tires are radial construction.

always buy the cheapest tires you can afford. Same for engine oil.

Save your old tires for your expensive boat trailer.

never balance trailer tires.

radial tires make the best tree swings.

"Not for Highway Use" is just a sales gimmick

Yes you can mount a 16" tire on a 16.5" rim. However, puttin the 16.5 on the 16 will require a tube at extra cost.

 

[rmw]

Let's see - maybe even use some engineering principles here.

First let's think like a Materials Engineer - Aluminum has a higher heat transfer coefficient than Steel.

Now let's think like a heat transfer engineer:

1. For the purpose of this simple exercise, let's say that the convection currents inside the wheel and outside the wheel are essentially equal between aluminum and steel - neglect any effects from spokes or center discs.

2. Let's say that the steel and aluminum wheels are equally clean or dirty so that the film resistances to air flow convection are essentially equal.

3. That leaves only the conduction through the metal of the wheel. Therefore refer to the sentence above that begins with "First..."

Now as PatPublican has noted, when braking, all the rules above apply, and any heat radiated or conducted from the brakes will conduct into the aluminum wheels faster than the steel wheels, but then again, what percentage of time is spent braking vs. running down the road, so overall, I think the Aluminum wheels win out. At least I did when I shelled out the cash for them.

rmw