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Old 10-06-2014, 05:55 PM   #1
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Airing down your tires - when and how much?

After writing my question yesterday about portable air compressors, I realized I don't know much about airing down tires. My main concern is rough, washboard roads that threaten to loosen my fillings with my tires at 65#. How much should one air down to smooth out the ride?

We have a 2WD rig so I doubt I'll be trying any sand dunes. But I would like to do something like drive to the Racetrack in Death Valley without feeling like I'd gone 10 rounds with Mike Tyson at the end.
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Old 10-06-2014, 06:38 PM   #2
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Re: Airing down your tires - when and how much?

I air down to 35psi for washboard, 45psi for rocky terrain and 20psi for deep sand. DV washboard is a killer at any PSI unless you go fast.
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Old 10-06-2014, 06:40 PM   #3
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Re: Airing down your tires - when and how much?

I usually go to about 30-35 up front and 40-45 rear on washboard but my van is heavy.

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Old 10-06-2014, 09:32 PM   #4
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Re: Airing down your tires - when and how much?

+1 on Tapatio's advice. You gotta go fast. Experiment with the speed until your tires are effectively bridging the humps. But be careful to slow down before turns.

It would be good to have BajaSportsMobile's advice on this topic.
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Old 10-06-2014, 10:22 PM   #5
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Re: Airing down your tires - when and how much?

As low as too can go without de beading or getting hot. My M55 tires tolerate 8psi just fine, even up to 20 miles on highway.
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Old 10-06-2014, 11:15 PM   #6
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Re: Airing down your tires - when and how much?

Quote:
Originally Posted by Tapatio
I air down to 35psi for washboard, 45psi for rocky terrain and 20psi for deep sand. DV washboard is a killer at any PSI unless you go fast.
Same here. I generally went right to ~35 psi for the rough stuff, and down to ~20 psi for soft sand.

I've recently calculated that my front tires (305/70R16) can generally go with lower pressures, as they carry less weight (4000÷2 lbs) than the rears (5500÷2 lbs). So for the fronts, I'm now playing with 35-40 PSI highway, and 25 PSI when aired down.

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Old 10-14-2014, 09:38 PM   #7
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Re: Airing down your tires - when and how much?

Hmmm, 2WD. Reduced tire pressure depends on the size and type of tire.. I have the 245 stock tires on slightly wider than stock rims and for good bad baja roads at lower speeds 30psi in front, 35 back is as low as I roll. If in sand one can go lower, but then the what if we swerve or hit a large something turning and roll the tire concern looms...

Those with the 4WD big meats can easily go lower....but even 35 front and back is pretty good on washboard as long as you go slowly....there is the go fast float school of thought, but when it goes wrong (harmonics, rocks, or slippery) it is a drag..at least from a baja out there point of view. Each road is different..You can and should always experiment.
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