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  #1  
Old October 29th, 2003, 13:48
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12.5 tire on 7" wheel

Is this possible? safe?
any pics....

thanks.
(not for me.. friend wants to know.. he has the tires and wants to know he can use stock wheels)
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Old October 29th, 2003, 13:52
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Bad Idea Jeans.

I was going to wear a condom, but then I figured "When am I going to be in Haiti again?'
In short, that sounds like a great idea, send some pics.
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Old October 29th, 2003, 13:53
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Re: Bad Idea Jeans.

Quote:
Originally posted by bgcntry72
I was going to wear a condom, but then I figured "When am I going to be in Haiti again?'
In short, that sounds like a great idea, send some pics.

This helps me how??
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Old October 29th, 2003, 13:55
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Everything I have seen says 8" minimum. See BF Mud TA chart below.

http://www.bfgoodrichtires.com/asset...rain_ta_km.pdf
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  #5  
Old October 29th, 2003, 13:56
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Thank ya bear!
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  #6  
Old October 29th, 2003, 14:06
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My Dad has been running 35x12.5's on his 7" wide rims for 4 years now without any problems. He wheels it, but not hardcore, and it is a daily driver.
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Old October 29th, 2003, 14:20
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if you put them on a jeep i would think they would rub the leaf springs ( i could be wrong but my 10.5" on stock wheels were super close)

also they would rub on CA's pretty good when turning.
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Old October 29th, 2003, 15:23
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The rule of thumb I've always heard (and used) is rim width + 4". That would make the maximum tire on a 7" rim an 11.

Can you run a 12.5 on a 7" rim? Yes. Is it "safe"? Dunno. If it spends any time of the street you'll get lousy tire wear, because the narrow rim is going to pull up the shoulders and you'll have to run very low pressure (unsafe) to keep the tread flat, or accept rapid wear in the center of the tread.
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Old October 29th, 2003, 16:27
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i ran 32x11.50 on a 15x7 wheel. in order to get the tires to run flat, i had to run 18psi in the front and 15psi in the back.
that was on a tacoma.

if i went around a corner any faster than 10 mph, i could feel the truck roll on the sidewall abit. But, i didn't have to airdown or backup when wheelin'

i don't think its safe to run at those pressures. Did the Ford Exploder tires come apart because of low pressures?
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Old October 29th, 2003, 16:47
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Quote:
Originally posted by hondastomper
i don't think its safe to run at those pressures. Did the Ford Exploder tires come apart because of low pressures?
That's what Firestone said. Ford claims they were defective tires. However, the same tires only self-destructed when run on Exploders at the relatively low pressure recommended by Ford. And after Ford changed to other brands, they were still having blow-outs -- that part of the story didn't get much press, as I recall.
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  #11  
Old October 29th, 2003, 17:09
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Quote:
Originally posted by hpi_jeep
if you put them on a jeep i would think they would rub the leaf springs ( i could be wrong but my 10.5" on stock wheels were super close)

also they would rub on CA's pretty good when turning.
Using the stock xj rims they probably would hit the leaf springs. My dad runs a blazer with stock wheels that are 7" wide. He likes to keep the sidewall in to protect it from rocks. I'd probably run an 8" or 9" wheel with the right amount of backspacing for 12.5" wide wheels.
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Old October 29th, 2003, 18:02
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you most definitely can run 12.50s on a 7" wheel, though the stock 7s probably don't have little enough backspacing.

I know a couple guys running 14.50s on 8" wheels and love it.

your tread will wear a little more in the middle though
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Old October 29th, 2003, 18:07
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I ran 12.50 s on a 6 inch wide rim and nothing happend of course this was for one day but still they worked fine
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Old October 29th, 2003, 19:14
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It can be done and is done quite often......

I run a 33x12.50 on stock spoke rims. it does not rub until it flexes. Very close to the leafes but does not touch. I'll try and get some images tomorow for you.
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Old October 29th, 2003, 20:39
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Re: 12.5 tire on 7" wheel

Quote:
Originally posted by Rufies97XJ
Is this possible? safe?
any pics....

A taller tire sidewall will allow you to run a more narrow rim.

31x12.5 on 7" = NO.

33x21.5 on 7" = NO (Maybe if you don't mind strange tread wear and poor street handling).

35x12.5 on 7" = Yes (the handling is not as good as with 8" but it's a very common combination in off-road racing).

37x12.5 on 7" = Yes (and the street handling is better than with the 35's -- considering any tire with that tall of a sidewall performs poorly).

The issue of rim backspacing, and the fact all 12.5 tires are not the same width and height, plays an even more important factor on the fit than rim width.

Some 12.5's fit, with stock 5.25 backspaced rims, and other do not. The tire sidewall is very close (IMO, too close for comfort if the spring leaf pack fans just a little, as sidewall damage potential is high).
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