33's = increased risk of rolling off bead when aired down & at 30-35 degree + angles?

Pointman1776 · 12-02-2008, 02:50 AM

I'd like to upgrade from my stock 265/75R16 BFG A/T's ('08 TT w/ TRD rims) to 33's.

However - I had a couple of close calls over the weekend with extreme 30-35 degree side angles. My A/T's were aired down to 16 PSI.

I thought for sure I was going to roll a bead. But I didn't. (Love those BFG A/T's!) But neither was I in a position to get out and examine the tire seat relative to the rim lip to see if I was in danger of rolling a bead or just fretting for naught.

Is there a increased risk of rolling a bead on 33's aired down to 12 or 16 PSI on stock TRD's when tipping past 30 or 35 degrees?

Or is it not a problem and I can upgrade without losing sleep?

Also, what is the maximum width of a 33" I can safely run on those rims at 12-16 PSI without rolling a bead? (Assuming I get a 3" ICON lift and chop the body mounts.)

(And yes, I used the search function before posting.)

Thanks for posting your experienced and expert recommendations!

Cheers!

**Brock** · 12-02-2008, 05:16 AM

i have never gone below 20lbs with mine so cannot help you.....but have heard a couple different people without beadlocks swear they are not going below 20 anymore but both are running the stock steelies.....

if i was airing down i would go for staun internal beadlocks I believe.

**1911** · 12-02-2008, 05:34 AM

I've had my 34" x 11.5" Toyo's on stock steelies aired down to 15psi at this angle in Moab and had no problems holding the bead at all:

***Shadow-Warrior*** · 12-02-2008, 06:03 AM

First off, if your running a stock wheel you should not exceed 20psi if you need to air down. Airing down should be done when in very soft sand or climbing a rock garden. Most people that don’t encounter these types of terrain really don’t need to air down at all. Now, I do know some including myself, like to air down some because it makes the ride more cushioned and comfortable.

If you want to air down under 20psi, then you need to change your wheels out to a bead lock. This is what they are for. With a bead lock, you can basically let all the air out of your tires and won’t loose the bead. Depending on the type of tire you have. This creates more outward forces to the sidewall, thus increasing the chance of failure with most stock tires.

I myself am getting ready to change out to a true bead lock, I wanted to when I started upgrading items on my rig, but the bead locks I wanted were pretty expensive. They still are for forged wheels and then you have cast and then steel bead locks, which are very reasonable. I hope this helps.

Mike

**Mtbcoach** · 12-02-2008, 06:05 AM

Its good that you are aware and cautious in this area. Yes, you can "pop a bead" when aired down.

That is where some tires perform better than others. I'd not venture below 15lbs unless it was a tire with an exceptionally stiff sidewall (like Super Swamper tires) and I've only gone below that in certain conditions. I'd say that the 18-20lb ranges is a good to be in. Again, that all depends on the tires and your experience knowing how hard you can push them.

This is a good time to bring up the important tool to have with you...supplemental air as in a Powertank or on-board compressor...

akoda · 12-02-2008, 06:24 AM

I have never gone below 20 in my BFG's. If you pop a bead on the trail is it easy to fix, assuming you have air?

Mike

Crotalus · 12-02-2008, 06:27 AM

In an EMERGENCY situation, you can always re-seat your tire bead with starter fluid or butane... Just don't do this in California...

YouTube - Setting a Bead on a tire, the fun way. Auto Addiction ltd

YouTube - Tire mount with butane

kp4zz · 12-02-2008, 06:58 AM

I have a 33's but I never use below 22 on the OEM wheelset, if you want go bellow 20 I'll recomend to change to bead lock

**Woodsman** · 12-02-2008, 07:33 AM

Quote:

Crotalus previously said:

In an EMERGENCY situation, you can always re-seat your tire bead with starter fluid or butane... Just don't do this in California...

YouTube - Setting a Bead on a tire, the fun way. Auto Addiction ltd

YouTube - Tire mount with butane

I'm gonna go out and break every tire bead I can today just so I can try that over and over again.

**FJ FunJunkie** · 12-02-2008, 07:35 AM

Ive ran 15 to 20 all the time on 33 baja claw radials and never had a problem, I've taken a corner too fast a couple times and had the truck on 2 wheels. Scary as hell but never slipped a bead. I'm also running stock steelies. Mabey I've just been extremely lucky. As for re seating it, the safest way is to always carry a ratcheting cargo strap, The 3 inch wide 10000 pound rated one, not the little skinny ones(unless thats all ya got, thenuse 2 or 3). You simply wrap it around the outside tread and crank it tight, this will push the sidewalls back to the rim. Make sure the sidewall and rim are clean of dirt and rocks or any other debris. then simply air up. A CO2 bottle is Ideal as it can give a short powerful burst when regulated correctly but if done correctly a compressor can work also.