5/26/2019 0 Comments The Hype Theory Glory Days ZipHow does rim width actually affect the stresses on a tire's casing. Lennard Zinn digs deeper into the physics of it. Dear Readers, Since, I have had some back-and-forth email exchanges with some readers about it. It’s evident that how I’ve explained it thus far has not been clear enough — some obviously intelligent readers remain unconvinced that increasing the rim width increases the stress on the casing of the same tire run at the same pressure. First, here is an interesting graphic on this subject sent in by a reader named Ross, followed by distilled versions of email exchanges with two other readers. I’m hoping that Ross’s graphic as well as some of the alternative ways of explaining it that I came up with will clarify it for those who still don’t see how increasing the rim width increases the stress on the casing of the same tire run at the same pressure. ― Lennard Dear Lennard, A few years ago, when wide rims and tires were getting a lot of press and hype with no apparent scientific evidence/backing, I went looking but came up short. I was most interested in quantifying the width and volume increase in going from a 20mm to 30mm inner-width MTB rim. Or road rims and 25mm tires. Long story short, I did a little calculation where I assumed that a tire would take a circular (this is a “first principle” type calculation) profile and have a constant distance from rim hook to rim hook for any rim (constant casing length). Then I grabbed a 25mm tire and measured the distance from bead to bead (basically just the casing “circumference”) and plotted the portion of the circular arc that would be formed for different rim widths. I’ve attached this plot for you. — Ross Dear Lennard,, you say that removing a 23C tire from a narrow rim and placing it in a wider one makes the tire wider, and then you must reduce the pressure slightly to have the same outward force on the rim. Paruthiveeran mp3 song download. I disagree, and here’s why: Yes, the tire gets wider. Download buku pdf biologi sma kelas 11 ktsp penerbit erlangga. But I think it surely also must get lower, meaning, smaller in overall diameter. When you pull the sidewalls farther apart, the outside area of the tire shouldn’t change. Instead, the center of the tread is pulled downward, in the direction of the hub, if that makes sense. If I’m right about that, the tire changes shape, but not volume. It just becomes more squat in section. So, the pressure should remain the same, and the force on the bead doesn’t change. ![]() Just thinking of a tire here, unmounted; the outside surface of it has x area. No matter how you wrinkle or fold or flatten it, if you don’t use tension that is constant. So why would it be different when you mount it on a rim and inflate? If the substance from which it’s made has, say, 3 percent elasticity in all directions at 100 psi it stretches to a set surface area that is y. Whether the rim has an internal width of 17mm or 20mm, the distance and construction of tire doesn’t change just because you mount and inflate it. Here is the simple image that troubles me: Take a rectangular piece of cloth (as a former member of a composites engineering team I can’t help but think about, say, biaxial dry carbon, but any cloth will do); set it flat on a table. Then push the long sides in toward each other until in section it is an upside-down “U”, similar to a tire. Now, slowly pull the edges back out — similar to a tire on ever-wider rims. The “U” loses height slowly at first, but eventually it is TOTALLY flat. It has zero height. Stream The Hype Theory - Glory Days, a playlist by Small Town Records from desktop or your mobile device. Oct 30, 2018 - And let's not talk about Auramancer's glory days. To the 'I feel great winning against backpedaler & mouseclicker with no condiclear hype'. At times to pull off but usually I just zip my pants up and use both hands to play just incase im slipping up. My theory is 'Those that can't Mirage, play condi'.
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