Airing down tips

TJim

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Hey guys!

give me some tips about airing down.

I now have only aired down to 15 psi. I am a little bit afraid to loose a bead.

So tell me:
1) how much is considered "safe" to air down on the trail? is this number different between tire sizes?
2) Does it depend on the terrain? (for example, mud, rocks, snow, sand, etc.)
 
I've gone as low as 10psi with my BFG KO2 32x11.5R15. This seems to be the lowest number I find on the forums generally considered "safe" without beadlocks and like you, I'm hesitant to push it because a lost bead can be a pain to deal with. I figure if it ever happens to me, my spare will be the immediate remedy.

I would expect the minimum safe pressure to be lower on bigger tires as there is more sidewall area for the air to push outward on, so the same tire pressure on a taller sidewall would result in more force holding the bead in place.

I would expect better results using a wheel that is equal to or narrower than the relaxed distance between the inner and outer bead, which is why you see 15x8 wheels as the most common recommendation here. You don't want the tire carcass working against you trying to unseat the bead.

I would expect rocks to be the most likely environment in which you'd lose a bead, because it's going to be the most likely to put concentrated inward pressure on the sidewall. Next might be mud with embedded tree roots.

Lately I've seen some wheel designs (I think Method is one of them) that have grooved serrations where the bead rides in an effort to better hold the bead in place. I don't know of any experimental data that demonstrates it's effectiveness.
 
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I usually go down to 8.5 PSI on 37 X 12.5 X 17.

It's more of a combination of your tires size, brand, and your wheels. 15 is too much for most trails with rocks. I would try going 1 PSI lower until you get to 9 or lose a bead (for harder trails). If you're doing easy trails, 15 might be fine.
 
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33's on 8" rims, I go 12psi most of the time and as low as 8 in soft deep mud and snow. The speed at which you drive on aired down tires will have an impact on how well they stay on the rims. 8psi means pretty slow so you don't spin one off the rim.
 
33 x 12.5 15 on a 10" wide wheel? No crawling. Soft powdery sand, light rocks and dirt access roads. I've been reluctant to go below 15 psi. Thoughts?
 
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Hey guys!

give me some tips about airing down.

I now have only aired down to 15 psi. I am a little bit afraid to loose a bead.

So tell me:
1) how much is considered "safe" to air down on the trail? is this number different between tire sizes?
2) Does it depend on the terrain? (for example, mud, rocks, snow, sand, etc.)

I run a set of 33's and a set of 35's, Used to air down to 15, as said above, it made little difference in ride. I now use 8 to 10 lbs. regardless of which tire I run and difference is significant. Haven't lost a bead yet on trails in Moab, Colorado, or Calif.
 
33x12.5x15s on 8" rims, load Range C. I'm very comfortable at 10, been as low as 8 at times in other trucks. It's good not too tax sidewalls on rocks too hard if you're not comfortable. I never lost a bead.
 
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For me personally, I experimented with psi ranging from 8-14 over several months on my local trails. I've found 11 psi to give the best balance of traction, soft ride, and not making steering a bear.

I find below 10, it gets hard to turn my rig on tight trails. Obviously if you're wheeling harder trails than I am, you might want to go lower. I've pretty much decided that if I start regularly wheeling in areas that dropping below 10 psi will make a difference, I'll start considering hydro assist.
 
33 x 12.5 15 on a 10" wide wheel? No crawling. Soft powdery sand, light rocks and dirt access roads. I've been reluctant to go below 15 psi. Thoughts?

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Sure.. I did.

Maybe I should have said.. I have 33 x 12.5's on a 15x10..


Are you suggesting airing down to 5 psi on a non-beadlock 33 x 12.5, on a 15x10 wheel?
:oops:

I just said what I've done. If you decide to do something similar that's on you.

There are many factors, including vehicle weight and driving conditions and style. I typically air down to 8.
I will say that if you can't see that a tire looks low on air then it isn't really aired down. Instead of pressure, think about sidewall height reduction vs street pressure.

For example, if you normally have 10" from the ground to the rim and airing down until the rim is 8" off the ground puts you at 80% of full pressure. This will give a noticeable improvement in ride and traction without great risk of losing a bead. Going to 60% will give you significant flotation for sand or snow but there's a bigger chance of issues in the rocks.
 
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