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Directional Tire Question

Discussion in 'Wheels & Tires' started by JimMiniS, Apr 4, 2011.

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    JimMiniS

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    I am now carrying a spare wheel (Style 162 - 8.0 x 18) mounted with a 225x40x18 Pilot Sports AS+ for my 2006 E90/staggered tires. This PS is directional.

    What will happen should I get a flat on the side of the car where the tire's direction is wrong? In this situation, would a couple hundred miles at legal speeds be a safety issue?
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    steven s

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    You can drive safely on a dry surface. Directional tires play a part in dispersing rain.

    ForcedInduction guest

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    In wet conditions there might be a minor difference, such as easier hydroplanning in standing water, but you're only talking one tire. I have tested directional tires in wet and dry and with some I was simply unable to detect any difference, which is odd, but it was the case. Thus you should have no real issues using your spare, just be cognisant of it in the rain if you need to mount it in the reverse direction .
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    CRKrieger

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    Agreed. I asked a couple different companies' tire reps about this years ago. They pointed out, as here, that it really only matters (and not very much) for water dispersal. You can drive 'backwards' indefinitely on them.
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    Deutsch Marques

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    If you put all 4 directional tires on the wrong way, your odometer will run in reverse. Or your speedo will go into negative numbers. Or you'll open a rift in the time-space continuum and destroy the planet in a burst of dark energy. I forget which. One tire for a short time might only cause the sun to go dark or something. ;)
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    JimMiniS

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    Thanks for the great replies. Now I have one less thing to worry/wonder about should I need to install the directional spare on the side that will result in it rotating the wrong direction.

    Regarding Deutsch Marques' comment, I had an inkling that putting a spare directional tire on the wrong side might cause the odometer to spin in reverse. But now I also realize that it will improve gas mileage by 25%. I can't wait to install all four the wrong way and never need to fill the gas tank again -- in fact, I will use the gas tank area for storing the spare :)
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    steven s

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    Although one more consideration is that your wheels are staggered.
    Be sure your wheel will fit on either front or rear.
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    CRKrieger

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    Buzzkill ... :p
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    JimMiniS

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    I hadn't thought of this :-(

    My E90 style 162 rims are 18x8 front (34 mm offset) and 18x8.5 rear (I recall a 37 mm offset). My spare is the same as the front, being the style 162 18.x8. Will this work for the rear? I'd hate to have to buy another rim...
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    steven s

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    I think as long as it fits the front, it will fit the rear.
    But I drove old cars.
    Might want to do a test fit before you find yourself on the side of a dark road, lost, in the rain, in the middle of nowhere. :eek:
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    CRKrieger

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    Yes, it will work. There are two potential clearance issues: tire clearance to the bodywork and wheel clearance to the brakes. The front tires are narrower than the rear, so they'll obviously clear the bodywork. The rear brakes are smaller than the front, so they'll fit inside the front wheel.
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    JimMiniS

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    Thanks for your logical insights about clearance issues. It sounds like I won't encounter any problems with driving on a spare should I ever need to do so.
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    Satch SoSoCalifortified

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    And less I rile the fanatics. . .

    . . . run-flats are getting better and better. . .

    :eek:

    :eek:

    :eek:

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