BajaNomad

tire preasure

bajabum - 7-3-2007 at 04:20 PM

I know alot of you have alot of experience driving off the beaten path and was wondering what your opinions were for what to air down to when driving down the many dirt roads of baja like the road from Puertocitos to Gonzaga, or from Chapala to Gonzaga or the road to La Gringa, etc. I drive a Dodge 1500 Quad cab 2 wheel drive and like to drive those roads fairly aggressively (50-60 mph). I normally run 35-40 PSI (cold) on the hwy but want to soften the ride a little. Does airing down make the tires more or less suceptible to flats?

Russ - 7-3-2007 at 04:30 PM

I found my Exploder runs better at 25# on the Chivato road and I still back and forth to town too. Also launch the boat over the beach. But for longer trips I'd go back to 35#+. But a loaded truck I don't know.

bajabum - 7-3-2007 at 04:35 PM

Bancoduo...HUH??? Please explain your strange response to a serious question

comitan - 7-3-2007 at 04:40 PM

Me thinks he thinks your not being serious when you say 50-60 MPH between Chapala and Gonzaga.(are you?)

woody with a view - 7-3-2007 at 04:47 PM

bancoduo is the resident left fielder...........60 mph on the chapala road = mucha cerveza.............:P

bajabum - 7-3-2007 at 04:48 PM

Well maybe not from start to finish, I have to slow down to a crawl in a few spots but alot of all 3 of those roads are straight and flat and unless you get up over 45 mph the wash board will shake your fillings out. 50-60 get you up on top of it and the suspension takes over.50-60 is the minimum speed I typically drive on the dirt! If the road allows I will push it up in the 70-80 range, guess Ive even hit 100 a few times! I am still looking for some serious input to my origianl post, I dont want this to turn into a thread about what some might consider unsafe driving!!!

BajaWarrior - 7-3-2007 at 04:54 PM

Too late

roundtuit - 7-3-2007 at 04:59 PM

Always found the higher the speed the easier the uncontroled DRIFT
:o:o:o:o:o

bancoduo - 7-3-2007 at 04:59 PM

Quote:
Originally posted by bajabum
Well maybe not from start to finish, I have to slow down to a crawl in a few spots but alot of all 3 of those roads are straight and flat and unless you get up over 45 mph the wash board will shake your fillings out. 50-60 get you up on top of it and the suspension takes over.50-60 is the minimum speed I typically drive on the dirt! If the road allows I will push it up in the 70-80 range, guess Ive even hit 100 a few times! I am still looking for some serious input to my origianl post, I dont want this to turn into a thread about what some might consider unsafe driving!!!
I'm a good person. If I ever see you all bloody & broken at the bottom of a cliff I'll throw you a "COLD ONE".:lol:

woody with a view - 7-3-2007 at 05:01 PM

Quote:
Originally posted by bajabum
Well maybe not from start to finish, I have to slow down to a crawl in a few spots but alot of all 3 of those roads are straight and flat and unless you get up over 45 mph the wash board will shake your fillings out. 50-60 get you up on top of it and the suspension takes over.50-60 is the minimum speed I typically drive on the dirt! If the road allows I will push it up in the 70-80 range, guess Ive even hit 100 a few times! I am still looking for some serious input to my origianl post, I dont want this to turn into a thread about what some might consider unsafe driving!!!


i think you can help US out here. how do you like the 70-100 MPH on rock solid tires? if the road is rocky, i'd stay hard..... less chance of a sidewall blowing. deal with the fillings when you get home......

mtgoat666 - 7-3-2007 at 05:01 PM

ya, airing down the tires helps alot. but optimum air pressure # depends on the vehicle and the tires. i do it visually, let some air out until i get a bit extra sidewall bulge, but not too much or you'll screw up your rim and maybe get pinnch damage to tire.
50 mph on washboards is certainly smoothest, as long as you don't endanger anyone and can see road far ahead. going 70 to 100 mph on washboards and smooth unimproved roads is foolish, as you can't see finner details of potholes and rocks far enough ahead to react and stear around them, unless you REALLY know the road
watch out for hot tires when aired down and pound out mile upon mile of washboard. tires get much hotter when they are flexing and air is squishing around.

bajalou - 7-3-2007 at 05:19 PM

Lower tire pressure makes it more succeptable to damage by sharp rocks. It's the air that keeps this from happening. So you have to keep enough in to carry your load. I too like to do about 40 or 45 or so on that trip - at least most of the way. Much smoother ride letting the suspension do what it's designed for. My vehicle's a lot lighter than yours so I can run about 15-20 lbs.

bajabum - 7-3-2007 at 06:37 PM

I guess it has to do with age and skill. Too young and your reckless and inexperienced, too old and you loose the need for excitment and your skills decline. It seems a few have a picture in thier minds of a truck flying down the roads at excessive and uncontrolled speeds with a mad man behind the wheel...its not the case. With the proper rig it is perfectly safe and advisable to let the suspension do the work and not beat the crap out of your vehicle. When the road permits its also fun and safe to get after it! There are many places where the road is fairly wide, semi flat with a little wash board and nothing for hundreds of yards on either side except for a few cacti. You can see for miles and to let loose in these places is what off road enthusiests dream of. Take the turn off at Chapala to Gonzaga...the first 5 miles is an example of what I am talking about. driving 50-60 MPH on a road like that is almost a must. ANYWAY...I am not looking for anyones opinion of HOW to drive. Pleas refer back to my original posting and comment on tire presure, if you dont have any opinion about tire presure please reserve your opinions to yourself :smug:

bancoduo - 7-3-2007 at 06:47 PM

Join SCORE and learn something, instead of being a runAway cowboy. The nature of your question tells me you are nothing but a Baja menace.:P

bajabum - 7-3-2007 at 06:52 PM

You must be one of the old ones...

bajabum - 7-3-2007 at 07:21 PM

Pro amnesty...what the heck does that have to do with tire preasure or driving skills? Too funny! I guess I should let this thread die and come back another day to get advice. I hope retirment solves the angst that seems to be embedded in your persona. PEACE, LOVE & FISH TACOS to ya.

DavidT - 7-3-2007 at 07:35 PM

I was on one of the straightaways between Puertocitos and Gonzaga Bay, running 70-75 mph.
And was passed from behind my a military Humvee running about 90, two of the soldiers were even standing up, and still had ahold of their rifles.
Used to rent a minivan from Avis, which we would drive to BOLA. Runs to La Gringa up to about 80 mph. Never lowered air pressure on any of those runs, so I can't answer your question.

I've ridden with Bajabum a couple of times, on the off roads on visible open straight runs he will crank it up. On the highways and in town he is one of the easiest going, alert drivers around.
He must be doing something right, 30+ years of driving in Baja without even a fender bender.
And no lost mirrors.

how low can you go

BFS - 7-4-2007 at 12:16 AM

Ive been running around with 12 lb and 15 lb (cold) pressure on the horrendous pothole roads around Todos Santos and it has made a huge difference. Fillings intact. But this is slow driving. On the long (rare) straights of washboard I tend to go fast too and with the low pressure it feels nice! Have not experienced more flats due to the low pressure. I used to run much higher pressure but after snapping a suspension thingie I was advised to air down and I feel it has made a big difference.
Aq

805gregg - 7-4-2007 at 07:11 AM

Cool bajabum, I feel the same way about rough roads. I will be driving Puerticetos, Chalpala next month, I usually don't air down (just lazy) but I will be going fast enough to smooth out the studder bumps, look for a cloud of dust.

BAJACAT - 7-4-2007 at 09:20 AM

It all depents on what your baja rig is equiped with,if you are running Fox suspention or equivalent,tire preasure it's not a issue, unless you are driving on some deep sand.
Im running Rancho's RX 9000 XL on my rig and on my last trip to Gonzaga,coming back via Gonzaga puertecitos Rd, I air down to 25 psi and I was averaging 45 to 50 /HR in some sections.If you don't have a high price suspention on your rig,lower tire preasure it's your best friend,air down to suit the terrain and your needs or may I say your knees hahahaahahha..

Gonzaga bay trip Memorial Day 5-07 072.JPG - 46kB

Cypress - 7-4-2007 at 11:31 AM

Been thru a mile or two of rough roads at work and at leisure.:biggrin: Wouldn't recommend zipping over miles of washboard with low pressure tires, sidewalls are thin and easy to puncture. :D Low pressure is great for sand, mud, snow, etc. Washboard is caused by the harmonic oscillation of tires on the road surface. You just have to adjust your speed to the washboard and be in harmony with the oscillations.:lol::biggrin: A smooth ride will be your reward.:bounce::biggrin:

Barry A. - 7-4-2007 at 12:32 PM

It has been my experience that "high speed coupled with low pressure" is not good-------it is a good way to pinch the tire against the rim when hitting rocks, thus causing tire failure, as well as exposing the sidewalls to rock damage, as has already been pointed out.

Slower speed (much slower than what you are talking about) and lower pressure IS good, and is usually the way I drive rough roads, the actual pressure depending on how heavy my rig is----heavy = higher pressure.

Shimmer - 7-4-2007 at 05:00 PM

I drive a '99 3/4 ton Suburban around the roads in and out of Todos Santos. I found that 25lbs saves the rig alot of ware... even over 30 lbs, which I used to run before I made my last discovery. As mentioned above the weight is the factor. I was surprised to find the difference in such a few pounds, but it is noticeable. I'm going to try working down to 20 to see which is the best for my weight.

S

Barry A. - 7-5-2007 at 08:04 AM

Shimmer----------

IMHO 25 is perfect if you don't carry a lot of stuff and drive at reasonable speeds-------I would not go lower unless driving really slowly, or you have super big tires and/or are in mostly sand.

For over 13 years of driving the dirt roads in the California desert, our fleet of 10 lightly-loaded full size 4x4 pickups used 10:00 x 15 tires, load range C, on 8" wide rims, and ran them at 26 lbs. and seldom had any problems, and they wore great, often getting over 30K miles before discarding.

We arrived at that tire pressure after much trial and error.

ClimbBaja - 7-6-2007 at 06:09 PM

There are some variables missing from your post, esp, the brand, size, and load range of your tires. Also the weight of cargo and/or camper.
Off hand, I'd say 22 to 25 psi would give you a significantly softer ride. That should also improve braking distance, provide better traction and steering control as the "footprint" or "contact patch" of the tire increases on the dirt.

As you air down, you should be looking for a smooth bulge of the sidewall. Some tires have stiff sidwall characteristics which don't show a progressive bulging, but rather do almost nothing until they begin to fold or crease. Crease = bad.
A smoothly bulging sidewall can probably be aired down to 12 psi for running sand (no rocks). 8 to 10 psi briefly to get unstuck. Running pressure in these low numbers will require you to carry a souce of compressed air.

[Edited on 7-7-2007 by ClimbBaja]

David K - 7-7-2007 at 09:13 AM

ClimbBaja is right on...

I have noticed that BFG All Terrain T/A's do not buldge very well and are thus not the best sand tire. Aggressive (mud/ snow) treads are also poor sand tires... In fact, the smoother the tire, the better, in sand.

In the 'old days' Armstrong Hi-Way floatation tires (sold by Dick Cepek) were great... they resembled aircraft tires.

Barry A. - 7-7-2007 at 09:27 AM

-------------and in the even "older days" David, we used aircraft tires with their straight grooves, and they also worked very well in the soft sand, as I know you know. :yes:

Things certainly have changed over the years. I still am a fan of BFG-AT all-terraigns, and have them on all 3 of my 4x4's.

TMW - 7-7-2007 at 09:53 AM

In the 2004 SF250 race Mike Doherty broke an axle in his class 8 truck. With one wheel drive he was getting stuck in the sand. We aired his 35x12.50 BFG tires down to 5 lbs (all 4) and he went thru the sand with no problem, running race speed, until near Matomi and hwy 5 he had to stop behind a stuck buggy and he too get stuck and timed out. At 5 lbs you could hardly tell they were low on air. Vanderway ran the entire Baja 2000 on 24psi in his class 8.