Tires

[carlkeigley]

I put nitrogen in my new car tires because I read an article that air leaks through the sidewall? and nitrogen because of cell structure is less likely to leak as much maintaining tire pressure. But how big a problem is it to check pressures once a week?

[carlkeigley]

Originally Posted by Byron Kinnaman

Is this the modern day 100 mpg carburetor?

Remember Obama's solution? Air up your tires. Don't drill for oil.

[floyd]

Originally Posted by Darwin Maring

According to Aircraft manufacturers the reason they inflate their tires with nitrogen is because they run cooler than regular air.

Imagine that! with all the miles aircraft put on their tires it could make a big difference...right? So how long before they impose a nitrogen surcharge?
I woulda thought they'd use Helium to lighten the aircraft!Probably stopped that when they heard a bunch of flight mechanics sounding like Mickey Mouse on the radio?

[floyd]

Originally Posted by Byron Kinnaman

Is this the modern day 100 mpg carburetor?

What's a carburetor?

[floyd]

Originally Posted by carlkeigley

I put nitrogen in my new car tires because I read an article that air leaks through the sidewall? and nitrogen because of cell structure is less likely to leak as much maintaining tire pressure. But how big a problem is it to check pressures once a week?

Since air is 78% nitrogen then all that other stuff should be gone after a couple of top-offs, leaving pure nitrogen... Right?.

[Francesca Knowles]

Originally Posted by floyd

Imagine that! with all the miles aircraft put on their tires it could make a big difference...right? So how long before they impose a nitrogen surcharge?
I woulda thought they'd use Helium to lighten the aircraft!Probably stopped that when they heard a bunch of flight mechanics sounding like Mickey Mouse on the radio?

Do you suppose the airlines are tracking nitrogen use to make sure that the mechs aren't using it to quick-chill their beer?

Francesca

[floyd]

Hey, why not use tires for CO2 sequestration and get a tax break?

[Jared J]

Originally Posted by Darwin Maring

According to Aircraft manufacturers the reason they inflate their tires with nitrogen is because they run cooler than regular air.

Yes, but if you've ever felt how hot they are after a landing, if the ones on your car were that hot, you were a runaway down a mountain, or on fire.

[Jared J]

Originally Posted by carlkeigley

I put nitrogen in my new car tires because I read an article that air leaks through the sidewall? and nitrogen because of cell structure is less likely to leak as much maintaining tire pressure. But how big a problem is it to check pressures once a week?

Again, air is already 78% nitrogen. I aired up my tires in both vehicles last fall, both of them are still good. Camper tires were aired up in October or November, still good. My 4x8 trailer sat unused for 4 years, they dropped down to 20.

It's not worth bothering about. I check them before a big trip and at fillups on big trips.

[Darwin Maring]

Just allot of hot air I guess.

[carlkeigley]

Originally Posted by Darwin Maring

Just allot of hot air I guess.

Probably.

I've concluded everything in life these days boils down to advertising.

[Brian B-P]

The air in your tires is not unstable - it's not breaking down.

Originally Posted by SilverGhost

The main advantage of NitroFill for tyres is the removal of moisture and oxygen. The oxygen likes very much to react with eveything it touchs - hence oxidation (rust). The moisture will expand and contract much more with temperature, especially if it changes state (vapor, liquid, solid) and will help along oxygen's work.

But, if you have a decent air drier on your air compressor the difference between with or without nitrogen is small. Definitely not worth paying extra for, but I'll take if if it's free.

Jason

Double Ditto!

[Brian B-P]

Originally Posted by Francesca Knowles

I thought you'd be interested to read that despite its business decision not to make trailer tires for smaller vehicles, Michelin does indeed subscribe to the notion that trailer tires are different in function and design.

That's not news to me - I mentioned it back in post #73, and in various previous discussions.

The optimization for a specific service is mostly about maximizing tread life. Since tread life is irrelevant to most recreational users, this optimization is of little value to us. Similarly, while Michelin builds specific drive and steer axle tires for commercial truck use, their model for motorhomes (the XRV) is an all-position tire: it is more like an all-season to the non-RV's straight summer tire, because traction matters more than tread life on a motorhome that will likely rot of old age before accumulating the hundred thousand of kilometers it would take to wear out.

Originally Posted by Francesca Knowles

You'll find their brief description of a trailer tire's form/function at this link. It's remarkably similar to Carlisle's, by the way...

There is a similarity in that both describe the optimization of tires for trailer service, although Carlisle says "a free-rolling trailer tire isn’t called on to turn, swerve and grab the pavement like a steer or drive tire" (apparently Carlisle-equipped trailers are guided around corners by some unseen hand from above), while Michelin says "trailer tires must withstand strong lateral and braking forces".

On the more controversial points that routinely arise in this forum, Carlisle and Michelin do not appear to agree:
Use of non-trailer-specific tires

While Carlisle's published statements have been interpreted here to mean that anything but an ST tire is inappropriate, in the sizes for which Michelin offers trailer-specific tires (only big commercial stuff), they also offer all-position tires (yes, the same tire on a steer axle, a drive axle, and a trailer axle).

Inflation pressure

While Carlisle apparently advises owners to always inflate to the sidewall maximum, Michelin says this in the Michelin X One Air Pressure Maintenance Practices (and example, the only document I noticed with inflation pressure right in the title):

Cold inflation pressure should be based on maximum axle load in daily operation

... followed by the usual load/inflation table. This is the same document, and the same advice, for both drive and trailer service (for which they have different optimized versions). It does not at any point suggest running tires at their maximum inflation pressure regardless of load, and does not direct air pressure to be handled any differently for trailer tires than for drive tires (this particular model is not typically used in steer applications because it is so wide).

[rabbit]

Hmmm. Dare I ask if the prescription of prestigious and respected Michelin holds any water--er--I mean air? I do.

jack

[floyd]

Originally Posted by Brian B-P

That's not news to me - I mentioned it back in post #73, and in various previous discussions.

The optimization for a specific service is mostly about maximizing tread life. Since tread life is irrelevant to most recreational users, this optimization is of little value to us. Similarly, while Michelin builds specific drive and steer axle tires for commercial truck use, their model for motorhomes (the XRV) is an all-position tire: it is more like an all-season to the non-RV's straight summer tire, because traction matters more than tread life on a motorhome that will likely rot of old age before accumulating the hundred thousand of kilometers it would take to wear out.


There is a similarity in that both describe the optimization of tires for trailer service, although Carlisle says "a free-rolling trailer tire isn’t called on to turn, swerve and grab the pavement like a steer or drive tire" (apparently Carlisle-equipped trailers are guided around corners by some unseen hand from above), while Michelin says "trailer tires must withstand strong lateral and braking forces".

On the more controversial points that routinely arise in this forum, Carlisle and Michelin do not appear to agree:
Use of non-trailer-specific tires

While Carlisle's published statements have been interpreted here to mean that anything but an ST tire is inappropriate, in the sizes for which Michelin offers trailer-specific tires (only big commercial stuff), they also offer all-position tires (yes, the same tire on a steer axle, a drive axle, and a trailer axle).

Inflation pressure

While Carlisle apparently advises owners to always inflate to the sidewall maximum, Michelin says this in the Michelin X One Air Pressure Maintenance Practices (and example, the only document I noticed with inflation pressure right in the title):

... followed by the usual load/inflation table. This is the same document, and the same advice, for both drive and trailer service (for which they have different optimized versions). It does not at any point suggest running tires at their maximum inflation pressure regardless of load, and does not direct air pressure to be handled any differently for trailer tires than for drive tires (this particular model is not typically used in steer applications because it is so wide).

Yes sir... Just as soon as I can figure how to cram a 445mm+ wide 22.5" tire into the wheel wells of my 13 Scamp I guess I would follow that particular Michelin chart!
They do warn that those are minimum pressures, but I could maybe run those tires with no air at all since the chart starts at 14000#. Now to find me some hoops to fit 'em up with a 5 on 4.5 bolt pattern!
Right now I can't even install 14s, so there's likely gonna be some needed mods But at nearly 4ft tall they're gonna look great on my Scamp and they're only a grand apiece!

[rabbit]

Thanks Floyd. Smelled the bait in the last parentheses.

jack

[Brian B-P]

I assume that both Floyd and Jack are bright enough to understand that the Michelin examples are large because they don't sell small trailer tires, and that the principles are the same in any size. I do appreciate the bit of humour. My parenthetical comment was about being wide compared to other heavy truck tires.

The point about pressure is that Michelin says explicitly to adjust pressure to suit load - obviously to at least the minimum - which clearly means not at the tire's maximum regardless of load.

[Brian B-P]

Originally Posted by floyd

Yes sir... Just as soon as I can figure how to cram a 445mm+ wide 22.5" tire into the wheel wells of my 13 Scamp I guess I would follow that particular Michelin chart!

Just one tire in a big well in the middle, facilitating a walk-around bed configuration, but unfortunately requiring the use of a special hitch to keep it from leaning over (custom built by Can-Am RV, of course).

[ruscal]

Back in the late 50's my dad bought a new Ford T bird. The car handled poorly and followed grooves in the freeway. The oem tires were probably Firestone bias plys and were so lumpy and worn out at 10.000 miles that my dad wanted to trade the car in for something else. He went up to Sears to get new tires before selling the vehicle. The tire salesman told him to try some Michelin X's, that were working really well on big heavy American cars. So they installed a set. No white sidewalls, only black. When inflated to the recommended pressure they appeared under-inflated. I remember my dad coming home and raving how the T Bird was a whole different animal. It drove smooth and quiet virtually transforming the car into something pleasurable to drive. Needless to say he kept the car! After about 50,000 miles the tires were looking about half worn, so he popped on another set. The ones he took off were worn evenly with no cupping or anything like the Firestone bias tires. Michelin was so far ahead back then it was a no brainer to keep buying them over the American options. They do know how to make tires. Radials by design seem to be laterally soft which may not be desirable for a trailer. Michelin is a radial tire company primarily, so may not want to build small trailer tires. The big truck michelins are often a lot wider than conventional tires which may provide some lateral stiffness. They take the place of duals in some cases. Most of the concrete trucks around here use them.
Russ

[floyd]

Originally Posted by Brian B-P

I assume that both Floyd and Jack are bright enough to understand that the Michelin examples are large because they don't sell small trailer tires, and that the principles are the same in any size. I do appreciate the bit of humour. My parenthetical comment was about being wide compared to other heavy truck tires.

The point about pressure is that Michelin says explicitly to adjust pressure to suit load - obviously to at least the minimum - which clearly means not at the tire's maximum regardless of load.

Nope, just not bright enough to equate semi-trailer tires with Scamp tires. Too many years as a fleet mechanic have driven the differences home. Heck, I'm so dumb that I see differences in P metrics among different profiles, brands, and compounds.
Besides even in the chart cited,they do warn that those are minimum pressures for the load. Anything below that on a road truck is a threat to other driver's safety. Pressures above the chart and below the maximum...not so much.
BTW,Am I to assume that Michelin wants you to decrease pressures at the unloading dock and increase them again at the loading dock? Doesn't happen... Fleet tires are set at least to the maximum expected load plus a margin up to the maximum sidewall pressure.