Tire pressure

[Oshkosh1]

Re: Tire pressure

Good Gawd...

We're talking a 250lb tinny here. NOT a big rig.

You people are WAAAAAAAAAAAY off in left field with your ridiculous formulas this, and semi-trailer that.

Like I said...deflate 'em down to around 45psi and you'll have a MUCH better ride. All this talk of impending tire failure is utterly nonsenseical when dealing with this load.

 

[dreamfly555]

Re: Tire pressure

If you ever walk across the launch zone of a drag strip you will immediately notice that it is nothing like a public road.
It is so sticky you will almost walk out of your shoes.
The amount of traction IS dependent of the area of contact when Glue is involved.

The friction Formula

F= u x N

Where:
F = Force of Friction
u = Coefficient of Friction
N = Force Normal to the surface. (Weight/Load)

Notice that area is not part of the equation.

There 3 laws of friction are:
1. The force of friction is directly proportional to the applied load. (Amonton's 1st Law)
2. The force of friction is independent of the apparent area of contact. (Amonton's 2nd Law)
3. Kinetic friction is independent of the sliding velocity. (Coulomb's Law)

Friction is counter intuitive. Watch This!
A brick, a block of wood, or even a sheet of plywood will have the same amount of friction no matter which edge or face you place on the bottom and drag across the driveway.

Yes, an empty trailer will be easier to drag with locked brakes than a loaded trailer.
Not because the tires are flattened less, but because it weights less.

Interesting read and I learned something.

From the video and from both 1 and 2 above, indeed the friction is independent of the area. However, the wear is very much depending on the area in contact with the road. If inflated to the max for a light load, the area in contact with the road will be less vs if less inflated. But since the friction will be the same in either case, the more inflated tire will have less contact area with the road. This less contact area will experience the same friction. Thus the wear will be quicker on that area. If it's less inflated, the tire will have more contact area with the road and the wear will be more spread out. Thus it seems we should adjust the tire pressure according to load to have optimal road contact to spread the wear evenly, our main goal.

 

[bigdee]

Re: Tire pressure

Interesting read and I learned something.

From the video and from both 1 and 2 above, indeed the friction is independent of the area. However, the wear is very much depending on the area in contact with the road. If inflated to the max for a light load, the area in contact with the road will be less vs if less inflated. But since the friction will be the same in either case, the more inflated tire will have less contact area with the road. This less contact area will experience the same friction. Thus the wear will be quicker on that area. If it's less inflated, the tire will have more contact area with the road and the wear will be more spread out. Thus it seems we should adjust the tire pressure according to load to have optimal road contact to spread the wear evenly, our main goal.

On the tow vehicle this is good info BUT on a trailer, who cares. Let's not get carried away on a simple issue.

 

[UncleWillie]

Re: Tire pressure

On the tow vehicle this is good info BUT on a trailer, who cares. Let's not get carried away on a simple issue.

Agree!

The trailer straight line Braking forces are independent of the Pressure.
It will make a difference if you are prone to spinning donuts with your boat in tow!

Low pressure causes more flex in the tire and it tends to heat up.
That heat comes from somewhere and that somewhere leads back to higher rolling drag and Lower Gas Millage.

Inflate your trailer tires to the max recommended and reap the benefits at the fuel pump.

 

[Home Cookin']

Re: Tire pressure

I think it's going to be a long winter already

 

[WIMUSKY]

Re: Tire pressure

^^^^^^^^ What he said.........
:deadhorse:

 

[emilsr]

Re: Tire pressure

I guess I need to add tire pressure to the list of emotional topics.....like what oil or wax to use or what brand of truck to drive.

 

[Thalasso]

Re: Tire pressure

I guess I need to add tire pressure to the list of emotional topics.....like what oil or wax to use or what brand of truck to drive.

:facepalm:
Instigator. :lol:

 

[beardeddone]

Re: Tire pressure

Ok our President said it so it is so it's settled

 

[fishrdan]

Re: Tire pressure

Low pressure causes more flex in the tire and it tends to heat up.

That's assuming his trailer/boat even has enough weight to even flex the sidewall of the tire......

He's hauling a 250# tinny, not 10,000# of bricks.

 

[cyclops2]

Re: Tire pressure

After the crummy original trailer tires start weather checking..cracking...I always replace them with Class B rated steel belted tires.

No problems. I do readjust tire pressure as days get hotter or colder.

ST tires are the worst quality you can buy. Why DOT & NHTA has not banned them after thousands of blowouts by unsuspecting people is beyond me.

 

[Hoobz]

Re: Tire pressure

For those of you keeping your tire pressures up to the maximum rating, you are weighing down your trailers to the max permissible load too aren't you?

You know, fill the boat full of bricks or something so it maxes out the trailers weight capacity.

May as well.

May as well hold the accelerator to the floor too, and never let the gas in your tank go below 90% full, just go nuts and go the max on everything.

Maximum, is just that. It's not the 'recommended' for towing a very light load. Only recommended for very light loads by folks who have marginal understanding or what a tire does. It cushions the ride.




Ahhhh...duh.