Comments by "EarthSurferUSA" (@EarthSurferUSA) on "Engineering Explained"
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When you add the effects of compression and rebound dampening (oil damper), this gets much more complicated than just a spring with no damper. In fact, a spring alone does a terrible job of keeping the wheel on the ground.
Playing with dirt bike suspension in the good old days of Motocross (using about 12" of travel), I found I actually got a plusher ride with a stiffer spring (front forks, and very little preload on the springs), that still resisted big bumps with less compression dampening, and more rebound dampening (assuming the dampers were set correctly with the stock springs).
As for the preloaded travel of a dirt bike, you pretty much want your suspension to have eaten up about 33% of the total travel with you on the bike, no matter what your spring rates are, and that is adjusted by a preload ring that compresses the spring.
But, if you add the dampening,--I bet the math work goes up exponentially---but it still has to work as well in the real world, and will need field testing to fix.
Sophisticated suspension, (depending on the demands and severity of the application), seems to be one of those things that almost never comes off the drawing table very well.
You should look at some of the front forks of MX bikes today. Nobody knows how to adjust them, there are so many knobs and air chambers. But one fork on Yamaha the kabaya (sp) SSS forks, that is over 10 yer old technology, and still uses a spring, romps them all in overall performance and probably every category.
You post great stuff young man. I hope there are more like you.
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+Engineering Explained
For a very stiff spring, yes, but what about a very soft spring?
Now the spring is under control of the dampening (compression and rebound dampening), to help the tire follow the road. But, for a hypothetical example, if the spring rate is soft (or not hard enough to rebound quickly), over stutter bumps, the shock could actually "pack" up into it's travel, because the next bump and next bump and the next bump compressed the shock more, and more, and more, until the spring rate is in a stiffer range of motion or the suspension bottoms out. When that happens, it could act a lot like a overly stiff spring, forcing the chassis upwards.
Selecting the correct spring rate for your application is probably more important than getting the dampening dialed in, but they have to work together, and it is usually futile to try to tinker with dampening if you have the wrong spring rate.
I learned something during the dirt bike suspension evolution from about 3" of travel to about 12" of travel. It was not always the longer travel that made a suspension perform better, but how well the spring and dampening handle the travel you have.
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If you fix a problem, don't you expect it to work better? The only problem with the car in the USA, (according to marx, your teachers, sorry), is that is peasant citizens made money and profit with them. commies hate profit,---but only when we make it son. You will figure it out,----------------------eventually.
Your entire generation, (worse than mine), better understand that education can only stat after graduation today. You should sue. Redefine "class action law suit", and sue for destroying your minds. You kids were figuring out reality better when you were learning to talk at the age of 2. Sue sue sue!!!! It's way past due.
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I was going to tear you apart, but you do make some valid points and have put a lot of thought into what you said. I have to respect that.
But you are wrong,-when you turn green for energy, (and I 'see being reliant on hydrocarbons as a problem at all, (I will refrain from the progressive terms "fossil fuel" and a new one to me, "Artificial fuel". The designer of that last one must have dreams of eating burritos to produce gas to power a bicycle that runs on the methane combustion,-- Oh, shoot, he won't burn his own "natural fuel" either. Damn it. :)
Now, if we want to "sustain" or even grow our lifestyles, I suggest we study the actual "dollar/power" (total cost per power generated) between all the power sources available, and I think you will find the only power sources that compete with the hydrocarbon in Nuclear.
But, if sustaining our way of life and comfort is not a concern, if our decline is not a concern--then by all means, (and all will be used),---save the planet.
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Be careful of the indoctrination word "sustainable", because it does not mean "growth". (do you want to grow?)
Sure, higher RPM's will mean more wear and tear, but with "growth" we can figure out how to make it work for their application, (tougher materials, better lubrication, etc. etc,--thinking). We are thinking man, and we can do anything that is possible, but only if we believe in "growth".
"sustainability" in reality, is actually a pretty dirty word, if you have any intention on growing. Consider it sabotage, as that is want the word represents in the context of mans "growth". I would love to see you young guys sue your teachers,---collectively.
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How would the oil companies, or any other industry, make it so other people can not compete with a new idea. You have the idea that is is all the companies fault, but if they did not get favors from our government, they would have to compete with the new idea. That is called economic fascism, and the "Tucker" automobile got destroyed by it in 48-49 after WW2. (Buy that 1988 movie, "Tucker", it is really good,but BS at eh end. It shows how government destroyed Tucker. It is true the auto companies did not want to compete, (The "Tucker" was a good, fast, durable, and safest car of it's time. 50 were made), but they would have had to if we had a true free market instead of the economic fascism that keeps you and I from the fun of competition.
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