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Old 12-11-2017, 02:56 PM   #1
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Aired Down question

This seems like a dumb question but I was once told the only dumb question is the one you don't ask

Ive been airing down to around 20 psi when loosing sight of pavement. There's been a few times when I've needed to connect areas with pavement. Is it safe to do this while aired down what distance and speeds are ok? So far i've just put my hazards on and crept along at 25mph for about 5 miles but how long is too long and how fast is too fast?

Also how about a surface such as dry lake bed? I came out of some rough terrain and found myself on a pretty flat and packed lake bed. In this scenario what would be a safe speed to continue aired down anticipating more rough terrain?

I have onboard air so I can always air back up but trying to avoid airing up/down constantly
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Old 12-11-2017, 03:28 PM   #2
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The biggest issue with driving above off-road speeds with aired down tires is building up heat, especially in the sidewalls. It may not be a problem at the moment, but it could weaken the sidewalls leading to premature failure.

Have I done it? Yes. Is it a pain to air up? Yes. Is there a general guideline about what is tolerable? Not that I know of.


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Old 12-11-2017, 03:39 PM   #3
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X2. Just don't let them get to hot, and take it easy to you don't roll a bead off the rim.

I've done 15 miles on highway 101 with only 8psi.
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Old 12-11-2017, 03:56 PM   #4
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Quote:
Originally Posted by carringb View Post
X2. Just don't let them get to hot, and take it easy to you don't roll a bead off the rim.

I've done 15 miles on highway 101 with only 8psi.


Yah ill stick to the if it doesn't feel right don't do it rule but on short connectors at low speeds sounds like it hurts my back more to air up than anything.
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Old 12-11-2017, 04:53 PM   #5
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I wouldnt worry about dry lake beds. Or at least I have had no problem flying down straight/long/flat sections that find themselves in the middle of a trail, ie soda lake on the mojave trail.
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Old 12-11-2017, 05:51 PM   #6
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Temperature is key. I put my hand on the sidewall. If it is warm they are ok. If hot then need to let them cool down and either air up or slow down.
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Old 12-11-2017, 06:06 PM   #7
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Another dumb question and DaveB would say look in the search dummy...but, is it (airing down) for pure traction or to prevent flats or both? I know i do it for sandy beaches (ie. Outer Banks SC) but not too much on w/SW trails that aren't too dusty/sandy...flats are the biggest paranoia (for me) driving off road..
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Old 12-11-2017, 06:09 PM   #8
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I'd say most of the time it is to smoothen the ride out. But it helps with the other reasons you mentioned as well.
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Old 12-11-2017, 08:07 PM   #9
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Traction because of the larger surface area in contact with the ground. Smoother ride because of the additional flex in the sidewall.
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Old 12-11-2017, 11:30 PM   #10
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If you're really concerned pick up something like this https://m.harborfreight.com/non-cont...not%20provided
And do some base testing with normal PSI to get some data then when you air down you'll have a better idea of usable temps.
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