Tire Blowout

Discussion in 'Prime Main Forum (2017-Current)' started by Ian Hertz, Apr 12, 2019.

  1. Trollbait

    Trollbait It's a D&D thing

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    I've heard a possible cause for the decrease with new tires is the mold release compound used during manufacturing. Guess it can cause a change to the very top layer of the rubber.
     
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  2. bresna

    bresna Active Member

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    I rotated the tires and have over 5,000 mile on them. I waited until after ~5K miles to post my story just to make sure it wasn't the result of them being new. I just think they don't roll as well as the Nanoenergy OEMs.

    BTW, I'm very happy with the noise and comfort level with the tires, just not so much with the mpg. I will always trade off a bit of mpg for a quieter & smoother ride but I've never taken a 10% hit before. That's just a bit too much with my 125 mile commute. It's even worse in that it kills my E range.

    I'll probably go back to Michelin after these to see how they do.
     
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  3. Trollbait

    Trollbait It's a D&D thing

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    Curiosity had me take a look at Tire Rack, and these may not be the exact same model tires you have and had.
    The AVID is listed at 21lbs per tire.
    The two Nanoenergies that came up in the Prime search are 16 and 17 pounds.
    Those aren't OEM according to Tire Rack. Those are a Ecopia EP422(18lbs) and Enasave 01 A/S(16lbs).

    Twenty pounds doesn't sound like a lot, but adding it to the tire is the absolutely worse place for fuel economy. Now, the AVID does have a max pressure rating of 51psi, which is part of why they are heavier, so increasing the tire pressure a bit could help counter the added weight.

    Funny, the Ascend GTs didn't come up in the Prime search there. They are a pound lighter than the plain Ascends; same pressure rating.
     
  4. BillKoz

    BillKoz New Member

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    I wonder how much air was in the tires that blew at higher speeds. I've read on this forum that some members were inflating their tires higher than the maximum recommended. Every tire is designed and engineered to operate within a safe pressure range. Under and over-inflating tires will have a negative effect on the performance and could cause a blowout at sustained high speeds.
     
  5. Trollbait

    Trollbait It's a D&D thing

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    Inflating a tire to the max pressure on the sidewall will only result in a blow out with a defective tire. They'll actually run cooler than tires set to what the car manufacturer recommends, as the sidewalls will flex less. That is also why the higher pressure is less efficiency. It could lead to uneven tire wear and less traction under some conditions. It will make the ride harsher.

    Under inflating is more likely to lead to a blow out. That was the issue with the Explorers, and why we all have TPMS now. Otherwise, it is a defect or damage in the tire as the main suspect.
     
  6. Mendel Leisk

    Mendel Leisk Obtuse Angler

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    Bridgestone similarly, has tires (Ecopia EP422 Plus) that come in multiple itterations. This tends to raise my consumer resistance "fur", make me look elsewhere.

    My take on overinflation, something I've just come around to in the last few years, is that the tires serve as part of the suspension system. They deflect/flex to absorb bumps/dips in the road. When the manufacturers spec a recommended tire pressure, they're balancing a lot of factors. Raising significantly above that spec, I think you increase the rate of wheel bearing and suspension wear.

    On the other hand, I'd speculate the spec'd pressure considers ride comfort as well.

    Weighing the above, plus the fact that tire pressures tend to gradually drop over time, I try to set pressures just slightly above spec, say a couple of pounds.

    Making that "interesting", I have various gauges, and none of them agree, lol. I use my my most easy-to-use one, but keep in mind it seems to read about 3 pounds high, at least considering the rest of my gauges.
     
    #46 Mendel Leisk, Aug 13, 2019
    Last edited: Aug 13, 2019
  7. BillKoz

    BillKoz New Member

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    I was referring to over-inflating (over max) the tire. You should never run your tires above the max recommended pressure. When you over-inflate a tire get hard and eggs the contact patch which reduces patch. All the contact is concentrated in the center of the tire. This will affect so many things depending on how much extra psi is added. The tire will wear uneven. The car's handling could become unstable (sliding, drifting and plowing). The tire's structural integrity will be compromised and could cause a failure (could see a belt shift or blow out). You have to realize as speed increases the tire heats up (plus overheating the center) the pressure will increase and by itself could cause a blowout, especially under an emergency maneuver or hitting a pothole. You could even damage a wheel when hitting a pothole. The real danger would be during a panic condition or poor weather. Also, the tire (sidewall) is very hard and will not help absorb bumps/impacts, they will be transferred to the suspension that will be overworking (over time). The tire will also transfer more road/tire noise and create a very harsh ride. Riding on the center of the tire will cause the engine to work harder and use more energy because you have less contact surface from the tire. I would not be surprised if overinflated tires could increase the stopping distance during a panic stop.
     
  8. Trollbait

    Trollbait It's a D&D thing

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    The car manufacturer recommended tire pressures are mostly around 35psi. Most tires have a max pressure of 44psi. That is a wide range before over pressure comes into play.

    The max pressure for a tire is for a cold measurement. The rating factors in the increase in pressure that will occur as the tire heats up from driving. Most of that heat is generated by the tire sidewall flexing as the wheel rolls along. Less heat is generated with higher pressures because the sidewall is more rigid and flexes less. The extra heat generation for sidewall flexing in tires underinflated is why they fail.

    The car recommended pressures are a balance between comfort, wear, safety, and tire longevity. The results may not be to the driver's liking. Higher pressures could improve performance, tire wear, efficiency, and resistance to hydroplaning for the potential drawbacks mentioned. The benefits could be seen before reaching the tire's max rating.

    Then the car pressures could simply be wrong. Many gen2 owners reported here that they saw increased wear along the edges of the tire tread with the tires set to the car's recommended pressure; a sign of under inflation. Tire wear along the width of the tread should be monitored no matter what pressure is used.
    How does that work? Higher tire pressures lead to lower rolling resistance, which means less engine work to roll them along the road.
     
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  9. BillKoz

    BillKoz New Member

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    The recommended max air pressure indicated on the tire also correlates with the max load rating. Something like 44psi will be good for 1700 lbs. load on that tire. Lower the psi. and the max load weight drops. ANYTIME you adjust the air pressure it should be done when the car has not been driven (ambient temp cold tire). The key to using the proper pressure is to have the whole contact patch touching the ground and NONE of the sidewall. An old school method of determining the perfect pressure is to chalk a band around the tire from the inside bead to the outside bead and drive the vehicle like you normally do. When you see the chalk worn off right to the edge of the contact patch where it meets the sidewall your good. Each tire may have different pressures.
     
  10. fuzzy1

    fuzzy1 Senior Member

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    This was the case with my 80s Accord ((kept until I bought a 2010 Prius) and spouse's similar vintage Integra (which she still drives). Both also hydroplaned too easily at the door placard pressure. Both were built before the infamous Ford Explorers for roll-over fatality infamy, for which a too-low recommended tire pressure was one of the several culprits.
     
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