Interesting Youtube video regarding bent wheels and yes, bent tires and an oven

Kestas

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The video talks about how bouncing strapped new tires on the ground will damage the beads. I find that hard to believe. I can't believe tires are that sensitive and not resilient enough to withstand what I would consider normal handling. Also, this video doesn't show how to repair a bent aluminum wheel as much as it underscores the importance of balance and runout.
 
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^ That and it was stretching truth that if the rim were perfectly true that they couldn't balance it. They just don't want the ever escalating amount of labor it would take to get it closer and closer to 0 runout.
 
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Originally Posted by Kestas
The video talks about how bouncing strapped new tires on the ground will damage the beads. I find that hard to believe. I can't believe tires are that sensitive and not resilient enough to withstand what I would consider normal handling. Also, this video doesn't show how to repair a bent aluminum wheel as much as it underscores the importance of balance and runout.
X2. There were a lot of wives tales about tires told in this video. I can tell you that as a tire manufacturer, the company I worked for treated tires a lot worse than the guy was explaining - and we have the data to back up that the damage is minimal. But he actually had a point about leaving a low spot in the rim so the tire's high spot can be matched up with it. That effectively cancels the 2. Ya' see, it's actually the 1st harmonic of run out that is the important value - the 1st harmonic being the best fit of a sine wave to the runout curve, The 1st harmonic is a calculated value that requires a computer to calculate and is typically lower than peak-to-peak value and is only sort of matched to the highest and lowest run out values. But it isn't critical to get the position exactly right - which why most people think in terms of the high and low spot. Why the 1st harmonic? Because vehicle suspensions act like spring-mass-damper systems and have a resonant frequency in the 50 mph to 70 mph range. Outside that range, the shock absorber partially dampens out the vibration, but within the range, the vibration is only out of phase with the input. Yes, there is more to this than just the 1st harmonic, but the 2nd and higher harmonics are generally smaller in value and the suspension resonates at different frequencies that are harder for humans to pick up. There's a long story about the time the company made a square(ish) tires where the 4th harmonic was the largest of the values and caused a rhythmic vibration that phased in and out at about 40 mph in an E-350 cargo van that set off the large side panels in the body of the van. The noise would drive you out of the van, it was so annoying.
 
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I took my Camry rims to this shop for straightening and powder coating Wasn't cheap, but a first class job Owner Mario was a stand up guy
 
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