Rim width

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Just got some maxxis buckshot 2s for a stock 2016 4runner in 265x70r17 load range C.

I'd like to run 18 psi front and 16# rear. I have 7" and 8" wide rims. Can also get 7.5.

At that psi, which rim width would decrease chances of popping a bead? Better to go more narrow or wider?

Thanks.
 

Mace

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That is basically a 31x10.50, at 18 and 16 psi either 7 or 8" rims will do fine. You might want to look at how big the safety bead is on each rim to see if there is a "better" choice. a 1" rim width won't make a huge difference. Those pressures are still not going to maximize your contact patch tho. A neat exercise is to actually make an imprint of the contact patch as you drop pressure. It'll surprise you how much of a difference 18 to 12 psi matters.



(keep in mind this is a general pic and not specific for the tires you own)

 
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That is basically a 31x10.50, at 18 and 16 psi either 7 or 8" rims will do fine. You might want to look at how big the safety bead is on each rim to see if there is a "better" choice. a 1" rim width won't make a huge difference. Those pressures are still not going to maximize your contact patch tho. A neat exercise is to actually make an imprint of the contact patch as you drop pressure. It'll surprise you how much of a difference 18 to 12 psi matters.



(keep in mind this is a general pic and not specific for the tires you own)

Thanks I appreciate the illustrations.

Based on the info now I'm considering running 15 front 12 rear. You think that'll be ok with stock 4runner wheels and no bead locks? Keep in mind I drive crazy.
 

Mace

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If you drive crazy, you can blow a bead at 35 psi..

Why are you concerned about differing the front and rear pressures?
 

Skniper

 
 
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That is basically a 31x10.50, at 18 and 16 psi either 7 or 8" rims will do fine. You might want to look at how big the safety bead is on each rim to see if there is a "better" choice. a 1" rim width won't make a huge difference. Those pressures are still not going to maximize your contact patch tho. A neat exercise is to actually make an imprint of the contact patch as you drop pressure. It'll surprise you how much of a difference 18 to 12 psi matters.



(keep in mind this is a general pic and not specific for the tires you own)

Nice chart, haven't seen that before. Kinda always associated a low pressure tire with increased width, not so much length of the footprint. It's a little counterintuitive since it's the sidewall bulge (width) that is most noticeable.
 

Mace

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Width does not change all that much really. If your tires are properly inflated, the full tread width is already touching the ground.

As far as front vs rear psi, I'd run them the same.
 
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Width does not change all that much really. If your tires are properly inflated, the full tread width is already touching the ground.

As far as front vs rear psi, I'd run them the same.
What's the reasoning behind same psi front and rear? Not meaning to argue or nothin just that I figure the back has the advantage of going lower since it's not a steer. Therefore increasing the footprint even more which would be especially helpful on an incline such as when climbing a dune.

But I'm really a newb and may be wrong about the whole thing lol. This is my first set of tires and I'm stoked!
 
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Nice chart, haven't seen that before. Kinda always associated a low pressure tire with increased width, not so much length of the footprint. It's a little counterintuitive since it's the sidewall bulge (width) that is most noticeable.
Most noticeable to the naked eye, yes. Careful with too much side bulge or too wide a ride as both can often increase the risk of puncture to the sidewall.
 
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Most noticeable to the naked eye, yes. Careful with too much side bulge or too wide a ride as both can often increase the risk of puncture to the sidewall.
Nice chart, haven't seen that before. Kinda always associated a low pressure tire with increased width, not so much length of the footprint. It's a little counterintuitive since it's the sidewall bulge (width) that is most noticeable.
Tire*
Nice chart, haven't seen that before. Kinda always associated a low pressure tire with increased width, not so much length of the footprint. It's a little counterintuitive since it's the sidewall bulge (width) that is most noticeable.
Too wide a tire*
 

Mace

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What's the reasoning behind same psi front and rear? Not meaning to argue or nothin just that I figure the back has the advantage of going lower since it's not a steer. Therefore increasing the footprint even more which would be especially helpful on an incline such as when climbing a dune.

But I'm really a newb and may be wrong about the whole thing lol. This is my first set of tires and I'm stoked!
Reasoning is that traction is best had at all 4 corners, not just the rear. But if losing a bead in the front is that much of a concern for you, then keep the front aired up.

Most noticeable to the naked eye, yes. Careful with too much side bulge or too wide a ride as both can often increase the risk of puncture to the sidewall.
Better to solve all the issues and get a tire with a strong sidewall.
 
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