Nitro filled tires.

[rockport]

Originally Posted by whj77372

Am I missing something, my D rated tires run with 65 psi?

No D rated is 65. My C rated are max 50 psi.

[OldCoot]

Originally Posted by rockport

No D rated is 65. My C rated are max 50 psi.

Don't understand, No D rated is 65, are you implying that D rated is not 65?

[jacknel]

One of the main reasons for using nitro is that it is not affected by temperature change. This is why it is used in racing tires. All the research I have done says it won't hurt but don't waste your money. If pressure drops you can simply add compressed air. I used nitro when I was a refrigeration mechanic to leak test because it was not affected by temperature, and a drop in pressure meant a leak in the system, not simply a drop in temperature.

[rockport]

Originally Posted by OldCoot

Don't understand, No D rated is 65, are you implying that D rated is not 65?

Saying d is 65, c is 50 and e is 80.

[B47]

Originally Posted by F and E Damp

The only tires that NEED nitrogen are those on jet airplanes. When I was at Boeing, I researched landing gear tire bursts. In the early 1960s there were several accidents that resulted from in-flight bursts of retracted tires, one with 70 fatalities.

The research showed that, if an airplane took off after taxying a long way with a dragging brake, there was a risk of either an over-pressure burst or a tire explosion in the first hour of the flight. We had a 727 case where the tire exploded from gases being released from the rubber compound and then spontaneous combustion. Analysis of the failed tire bead steel cords indicated a pressure of about 12,000 psi!

If your rig can do 150 mph for a couple of miles (with a dragging brake) and then retract the wheels, by all means spend the extra.

The landing gear tire bursts were not the only reason. The FAA issued Airworthiness Directive 87-08-09 requiring nitrogen to be used to prevent explosions resulting from overheated brakes and the subsequent explosions.

[denandra2]

you mean no one else changes their air from summer to winter? just BURST my bubble!!!!!!!!

[B47]

Originally Posted by denandra2

you mean no one else changes their air from summer to winter? just BURST my bubble!!!!!!!!

Sorry

[garbonz]

Originally Posted by kb4srn

I'll let them down to 50 psi tomorrow. Meanwhile, Old Coot, I'll make sure not to jar them. Thanks for the advice.

Collect the air in a bag and then hook it up to your compressor inlet when you fill again, and you can recycle it. I wish they would use helium so that our rigs were lighter. Or maybe nitrous oxide so we could laugh while we fill.

LOL

I LET 5psi out of mine and felt a little guilty.

[rockport]

I was surprised with the pressure change while driving, went from 50psi cold at start of trip, up to 60-61 psi after driving for a couple of hours. This was according to my TST tpms system..

[garbonz]

Air pressure changes about 1psi for every 10 deg of pressure. So if your tires were at 70 deg F to start they were at 170 deg at the end. What did your TPMS say about temps?

[rockport]

Originally Posted by garbonz

Air pressure changes about 1psi for every 10 deg of pressure. So if your tires were at 70 deg F to start they were at 170 deg at the end. What did your TPMS say about temps?

That's a good question. Trip was couple weeks ago and I don't remember temp numbers, I'm sure it wasn't 170 or I probably would have been freaking out thinking that's way to high. Seems like I remember around 100 degrees or so.

[garbonz]

At 100 deg you should have only seem a 3 psi increase.

Hmmmm. I wonder what is up here.

[rockport]

Originally Posted by garbonz

At 100 deg you should have only seem a 3 psi increase.

Hmmmm. I wonder what is up here.

Next trip I will keep a log of psi and temps to try and figure out.

[OldCoot]

Originally Posted by garbonz

At 100 deg you should have only seem a 3 psi increase.

Hmmmm. I wonder what is up here.

Ours gain from 5-10 lbs also and the temp never gets close to 170° I have the alarm set at 157° and it has never gone off.

Maybe your data is not applicable to tires?

[BarryD0706]

Originally Posted by OldCoot

Ours gain from 5-10 lbs also and the temp never gets close to 170° I have the alarm set at 157° and it has never gone off.

Maybe your data is not applicable to tires?

X3

Perhaps the issue is the vaporization of the water in the tire. It doesn't follow the "ideal gas" rules.

[jadatis]

I once asked a stemm-importer about the pressures for stemms.
The information I got was that the stemms are tested to stand the pressure-rising from 18 dgr C /65dgr F to 100dgrC wich is boilingpoint of water, convert it yourselves. This can happen incidentically by the heat of the brakes transported trough the rimms. The maximum pressure of normal rubber snap in stemms ( the 400 series) is 4,5 to 4,8 bar ( 65 to 70 psi ) at 18 dgr C/65F filled, and an extra pressure by temperature rising of 1,8bar/26psi they are tested for at the mildest american standard.
Thought it might be interesting to know.

The 1 psi at 10dgrF rising is a rule of tumb, wich does not go for larger temperature or pressure risings. I once made a spreadsheet for playing with the temperature and pressure, and filled in the 50 to 60psi rising rockport gave
here the picture
Mind that what the tpms gives is not always accurate

[OldCoot]

Originally Posted by OldCoot

Ours gain from 5-10 lbs also and the temp never gets close to 170° I have the alarm set at 157° and it has never gone off.

Maybe your data is not applicable to tires?

According to http://members.home.nl/jadatis/press...onwithtemp.xls

My tires would have to gain 14 lbs to set the alarm off @ 157° if I set them @ 65# when the temperature was 65°.

[OL Creeker]

I hope you guys are kidding about the nitro tires going bang! You do realize "N" is an inert gas, right?

[OldCoot]

Originally Posted by arjerram

I hope you guys are kidding about the nitro tires going bang! You do realize "N" is an inert gas, right?

Understand exactly that nitrogen is an inert gas, but nitro which is what the op posted is slang term for nitroglycerin which will go BANG!

[roanmountaincampers]

I'm the OP and the sticker on the side of my TT says tires are filled with "Nitro". I go over speed bumps very slow. ( Just kidding).