Thinking about tires
With the issue of the tire/wheels I bought from Northern Tire having an under rated wheel got me to looking deeply into tires and have come to a simple conclusion. A tire's enemy is heat.
From that simple statement comes a wealth of concepts and considerations.
First: an overloaded tire will run hot. A tire rated at 2150 lbs at 65 psi may have an effective rating under 1800 at 50 psi. Underinflation is your worst enemy.
Second: radials run cooler than bias ply tires, bias ply tires have no place on modern vehicles.
Third: drum bakes transfer heat directly to the wheel. If the brake is dragging even lightly, it will run hotter than it should.
Fourth: a narrow wheel will load the center of the tire and it will run hot. With a wider wheel the proper inflation will put more of the load at the edges. Even a 205 should have at least a 6" wheel. 225 a 7".
Fifth: Trailers in general have a higher CG than a car. This puts a higher load on the outside tire in a turn than on a car tire. It also has a fixed camber (usually zero). (Note: if a tire is rolling a lot in turns, you will see a scuffed area extending up the sidewall from the tread. The more you see, the worse the roll.
Sixth: If the tire has a "ST" anywhere in the model name or size designation (e.g. ST225x75R15) that means "Special Trailer" and it has a maximum speed rating of 65 mph. Period.
Seventh: Salesmen do not know. Always check specifications at the manufacturers, they all have a web site with specs.
OK so the worst thing you can do is to come down a long mountain Interstate with a lot of curves maybe a little too fast and riding the brakes. The engine/oil/trans will cool right down but not the tires which will be getting hotter and mose stressed by the mile. Hot day won't help but we are talking 200F and beyond.
Just as an aside back in my yout the SCCA had a class called Showroom Stock Sedan which was mainly econoboxes under 2000cc. One of the requirements was 165 section width tires and no more. Must be DOT approved. The hot ticket was Michelin XASs which essentially became slicks when pushed hard.
I had a Mazda 808 coupe that had better gears/power to weight/few other things than others. It would fly.
For the first outing I just left the stock 165s on which were not Michelins. Now I tend to be a bit of a squirrel and figure the only time I should be pointed straight is when exiting a turn ( not travelling straight, just pointed that way (later when serious about a 78 Sunbird I used to break a right front wheel nearly every weekend).
So spent a full practice session learning the car which for me means pushing too hard and seeing how it recovered. At the end of the session I pulled into the pits and stopped for a bit before heading back to the paddock. Except the car would not move, the thoroughly ex stock tires had melted into the pavement. When we pried it loose the cord was visible.
Next outing I had XASs.
Bottom line: heat is your enemy and much more than any brand, with a few exceptions (anyone remember the Firestone 500 ?) they are all made well and those with a nylon cap are better.
Tires do seem considerably better now than just a few years ago but the major problem is heat. If you can't rest you hand comfortably on the tread at a rest stop, something is rong IMNSHO. A little Harbor Freight IR gun can be very handy as the tread should be an even temperature across the width (good for a lot of things from measuring ac performance to identifying a misfire but this is an important one).
So keep inflated, don't pull over curbs, try to miss potholes, slow down on long downgrades, and "drive gentle". Given that, the brand probably does not matter much. They may all be from the same plant anyway.
Comment ?
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Looking for a 24/17 in or near Florida.
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