I lol'd

The guy wasn't drifting when it happened, probably was over inflated though, 40-45psi.

I know the guy. lmao Just throwing that out there.

The truth of the matter is I'm not going to waste my time and vacation doing the math when you admit the followingDo you see the issue? What's the point in doing something when you don't understand it from the get go? I mean, I don't sit down and work with viscoelastic materials for a living, I don't work with aluminum impregnated 'tire rubber' and run simulation after simulation of stress and strain in FEA for both pressure and temperature variations. Perhaps you should look at some of my posts before pretending you know the first thing about what I can and can not do. I mean, solid rocket motors have no bearing on anything engineering related... oh wait.

Let me put it another way; why should I waste 1-4 hours of my life to prove something to you that you would not believe or understand in the first place.
Let alone do it pro bono?

You're right. Good thing I'm not pretending. Material Science, Computational Fluid Dynamics, Kinematics, Thin wall structures are just a small portion of my interests and occupation. Do you really want me to teach you the very basics so you can even hope to understand the math behind non-linear material deformation and stress levels? How about I just hand you a book for you to read so you understand the basics.

You change you're own points, and have yet to address the issues I've raised. I've already given you enough information to understand the science on a basic level. Which according to your previous posts show that you have yet to even attempt to understand but attempt to dismiss Material Science as theory (which you still have yet to concede).

Yeah, but not everyone is able to cut through your BS as effectively as me and waste my time in responding to you (remember you said I belittle you in one of your first posts, this is what belittling from me feels like and I have a large resivour to pull from if you want to keep going).
Unfortunately I have justified my point using material science (which contrary to your made up definition is not theory).
Then you have no idea what theory and science is and how they work together. Let me put it this way: Science is the application of laws and mathematics to model and derive real world outcomes from basic knowledge. Theory is used to test via the scientific method. For instance: Material science allows you to design, build, and test various materials and their behavior under duress. From the wiki article previously posted:
No. Sorry. It's not.
As has already been shown. The science I've stated is fact. Whether YOU choose to believe it is of little consequence to me. You have as of yet, failed to address any of the numerous points I've brought up. It also appears to me that you fail to understand the basics of this science on a fundamental level. Which leads me all the way back to this point: If you don't understand how the tire is deforming or being stressed, what are you doing stretching the tire in the first place.

In an effort to help YOU better understand the science behind the deformation of the tire. Let's start even more basic than material science. What forces are acting on a tire (entire wheel assembly rim-tire combo mounted on a running car--We'll keep it simple. 2D only for right now)?

I dunno if this was a joke...

40 - 45psi "overinflated"?
We've run 60psi+ in autocross without any ill effects during the runs.
I've seen guys run inflations up to 80psi at the autocross without blow-out's.

Of course, this is with PROPERLY sized tires to wheels.


-Ted

I've ran 60psi too. I'm just guesstimating. I don't know why you'd wanna run tire pressure that high though, especially during autox. Hell, I seldom go over 35psi while drifting now. I'm just saying, since people are bringing up factory recommendations. I don't really think I've ever seen any cars with a suggested tire pressure close to 50psi.

There are BMW's with recommended tire pressure above the normal level (at least that's the rumor I've heard).

I guess it would depend on the setup/track. On the smoother courses I find myself running higher pressures, on the lumpier tracks I find that tire deformation is my friend.... as is the case in the vid I posted were the tire was moving all over the rim but traction was maintained even when exiting a corner HARD on the gas...


Of course your experience may and probably will differ

Yeah, I can see what you mean. Can't really say a lot, just due to the fact that I've never really done the whole autox thing before. So I don't have any experience there.

Vex...

Note how the application of laws AND MATHEMATICS are used to model and derive real world outcomes? You're refusing to do the math under the premise that you're right? Prove it. As for thinking you're so intelligent that I wouldn't understand the math because I'm somehow beneath you for not going to the same classes as you in college? Jumping to conclusions again. I can't write programming for shit either, but it doesn't mean when a program isn't working I can't look at the code and see flaws in it. That doesn't mean I can program from scratch though.

The part I don't get is how you still can't understand that without the math you're speculating based on your understanding of the materials. YES, IT IS WEAKER. NO, THAT DOESN'T MEAN IT WILL BREAK. The math is what ties your your information about the materials to the theory that it is unsafe or will break. Without the math, you're talking theory.

If you want to argue dick size or IQ I've got enough of both. I'm not trying to argue that, I'm trying to argue that you can't stamp something as a fact without testing it or doing anything to prove it. I can cut through your BS and see that you aren't willing to do the math because of one of 2 options, 1) you don't know how (which based on your line of work I'd imagine you probably have the formulas) or 2) you're afraid that the math might give me more to argue with.

I understand the laziness factor; I wouldn't want to do 1-4 hours of math either to prove a point. But without it you're speculating. If you just admit that without the math you're speculating, then we can move on. As someone in the field of this type of mathematics I would venture to say that if you can't admit the math ties your premise to facts then I wouldn't imagine you're very good at your job. It's cool, some engineers get into the field because they heard there is money in it, not because they're naturally good at it.

Oh as for your question, I'm not sure what you're looking for here so I'll just list some stuff off the top of my head and let me know if I'm close to what you're looking for...
Tire pressure, weight on the particular wheel/tire, temperature of all materials and outside temperature, what the tires are filled with (nitrogen, air, helium), The stretch of the tire (still an inch and 1/2 of difference between the recommended wheel widths for a given tire without being outside of spec), the materials used for the wheel and tire, and camber.

Once in motion I would guess...
friction, shock/spring combination, lateral forces and additional compression from the various loads during cornering, braking, acceleration, bumps in the road, wheel/tire balance, toe, and caster.

I'm sure you'll find something I missed, but that's a basic list of shit off the top of my head.

I really can't understand why it's so hard to admit that mathematics is required to prove your point. Without it the only thing that you can say for a fact is that the tire is weaker, weaker =/= failure or unsafe.

@Rotordad
Your argument is valid. If it's not your preference don't do it. I agree and I'm not saying it's the coolest or that anyone should do it. I'm just arguing with Vex about concepts of calling something a fact without proving it. EVERYTHING in this thread is speculation. Lots of facts have been stated, but none prove much. I haven't argued at all (not thinking it was directed at me but just commenting) about people needing to slam their cars or stretch their tires. I have my drift car highly modified that is slammed and stretched, but I have stock cars too. I understand the desire for a comfortable street car. Stretched tires aren't horrible on the street, but if your suspension is stiff they remove even more absorption.

@RETed
The 80psi argument sounds remarkably similar to the stretched tire argument. Though you appear to be backing the inflation out of spec, but not stretching out of spec. Just pointing out the similarities of the arguments, not trying to debate another one. I can see that you're also arguing for track purposes and not street driving. I also wouldn't be able to perform math to prove the air pressure thing either way. But I definitely see similarities between the arguments.

Holy shit. Do you know how uneducated you sound when you typed that? Here's some sample FEA, tell me if it's going to fail:

http://www.designworldonline.com/upl.../mar-fea-1.jpg
http://www.schultz-creehan.com/Porta...-pic-FEA-2.jpg
http://www.ctd-materials.com/images/FEA%20Tank.JPG

Look up spring mass damper systems if you're a little hard pressed to understand. From there pick this book up:
http://www.amazon.com/Deformable-Bod...662630&sr=1-10

Once you understand those we'll have something to discuss.



There is not a face palm big enough for what you just typed.
Apparently not, but your foot size sure seems sufficient to keep putting in your mouth.
Do you need to do math to understand a weaker material is present based on geometry? Nope. Do you need to do the math to tell you a material is an insulator or a conductor? Nope. Your argument is a logical fallacy.
We'll work with what you posted.
YesAre not forces and are not needed for a preliminary analysisAgain not really needed, but good to know.This confuses me a little. Are you saying preload of the tires deflection? Yes Yes, but only dictates the location of the force acting on the tire.
Okay, how are you going to calculate that force? Static friction, dynamic friction, all are based of the weight of the wheel in question. Furthermore different compounds have different friction values. Only matters if you're doing an unsteady deformation analysis (which isn't even done for rocket engines)Then it's not exactly 2D is it, but for 3D analysis is spot on. Which are... what exactly? Again, dynamic, but not really needed for preliminary analysis. Is not a force. Is not a force. Only needed for 3D analysis.
Which has basics of it, but are not everything we need. I'm keeping it simple for your benefit.
Nor have I intimated it as such. I have stated that deforming a tire outside of manufactures spec prior to normal driving forces will weaken the tire. The difference is do you know how much weaker the tire has become? The obvious answer through your posts is of course, no; you do not.

Now that we have a rough idea of forces I'm going to ask you to draw a picture. Draw a circle. This circle is representative of a tire. Draw the forces on that tire. (I'm thinking of the view you'd get if you looked at a tire from the side) Draw the forces for friction, weight, pressure, etc.

In determining the stress levels we have to use statics (unless you want to do dynamic analysis which is a whole bunch of worms worse than what you think is possible). That means, application of the forces must result in 0 displacement of the body--or the body must undergo stress to maintain unity. But that's getting ahead of ourselves. Lets keep it simple.

Draw a circle and place those forces you've described.


(Just for future reference:
In mathematics, a proof is a convincing demonstration (within the accepted standards of the field) that some mathematical statement is necessarily true. Proofs are obtained from deductive reasoning, rather than from inductive or empirical arguments. That is, a proof must demonstrate that a statement is true in all cases, without a single exception. An unproven proposition that is believed to be true is known as a conjecture.)

Nor do you without the math, and thus stating it's unsafe, or stupid would be a statement of your opinion. Thus you have in fact intimated it as such by going on with all this scientific bullshit that's unrelated. All you had to say 25 posts ago was that you're not stating fact, you're stating your opinion.

Cool, an obscure definition. English is sweet how all common words have multiple meanings. I'm looking for proof as in definition 7, not definition 8.
http://dictionary.reference.com/browse/proof
Can you provide it or are you just rambling to make people think you're smart? I wasn't the one that insisted on having it all posted public, I genuinely want see proof (definition 7) stating that it's unsafe. When the argument was deleted I sent a PM (which you posted up here on the new topic so I didn't have to) that said I'm not trying to be an attention whore, I'm trying to get you to prove your point. You replied:
Which leads me to think that it's more important for you to sound like an asshole trying to talk over my head than proving anything. I already said I am not an engineer, nor do I plan to be. That doesn't mean I'm not intelligent and can't debate. Be a condecending asshole if it makes you feel good inflating your ego because you went to college and learned some shit. I can talk over your head on subjects too, but I don't think that makes me smarter, just means I know some shit that you don't. If I spent the time I could do the classes for engineering, seemed boring to me so I went to school to work with computers.

Now for the sake of argument I'll show where you implied (and even stated directly), but flat out stated that it's unsafe to stretch tires...
Page 3
Page 3
Page 4
Page 5Those are all verifiable proof (definition 2) that you stated that it's unsafe and will prematurely fail. Now provide proof (definition 7) that the sidewall failure will happen before the tread, or remove the premise that it's unsafe. I am not arguing that it won't weaken the tire, I'm arguing that based on experience I think the tires will last through the tread before the sidewall fails on my stretch.

Being an asshat trying to flex your brain doesn't usually work like this, huh? Most people just roll over and die. I'm not wrong, you're just requiring every possible variable. How very, engineer of you. Can't think for yourself or understand plain fucking english until everything is defined. Now that you have the exact definition of proof I'm looking for I look forward to your next attempt to pick apart my words to some rediculous definition that I clearly don't mean. Being a condecending dick only works on someone who doesn't share high IQs, I choose not to be a part of MENSA, I do qualify. I found a lot of your type of people there and didn't enjoy the company. (Intellectual types that get off on being better than the rest of humanity)

As for your exercise in physics in 2 dimentional form, I see no point in going through this because you're not trying to teach me anything, you're trying to point out how much more intelligent you are. Which is to say how much more you know on the topic. I listed all the factors I could think of that would relate to the topic, 2 or 3 dimensional. If the car is parked or moving would define other metrics. Caster would effect it on 2 dimensions based on the angle the weight is applied. Toe would only effect it while moving. Bumps in the road while moving I would think would be considered a force, but I'm willing to listen to any reasoning you have there. And how is acceleration not a force? Centrifugal force? Torque? These things appear to be forces to me unless we're using an obscure definition of force. I'm using 12a, which one are you using?
http://dictionary.reference.com/browse/force
Answering beyond what you asked for recieves much criticism as I expected from replying to just what you said. Fuck yourself, you think as an engineer that acceleration isn't force on a tire yet braking is? Awesome, please continue to take me to school. Why don't you draw the diagram and make your point, though I'm not sure what information we're going to gain from calculating the 2 dimentions of a 3 dimentional object. Hopefully we can skip to that too.

I didn't say I know the specifics, I could do the math and give you a made up number that has no bearing with the discussion because you'll reduce your stance to the point of absurdum. Let me see if I can be plain for you: From what you've quoted of me in this thread (here comes your reading comprehension).
This you agreed with when you stated:
and from a tire company itself:
So, I think your point becomes moot in that respect.

Is there anything in particular you find incorrect about that statement? If so, please, pretell what is it? Incorrectly mounted tires also negates the speed rating (as the speed rating is set by standard mounting of the tire). Any issue there? Didn't think so.
Lol, mathematic proofs are not obscure in any sense of the word. But from your link:
You do realize we are not discussing arithmetic at all yes? If you did not know that, let me help you: Arithmetic
Differential Equation
Is more closely related to the science at hand, and hence not arithmetic. If it were simple arithmetic then sure I would do a problem for you without protest. Hell I imagine you could do arithmetic without issue.

Now, back on point: Proof. I personally like definition 7 as it works fine for me, but definitions 1-4, 6-9 (just as a point of clarification I'm attempting to help you along definition 8 in understanding the application), the remaining definitions are of non-use in this application. So I do not think you helped your case any. Just sayin'.

Now back to that quote of mine.

Which is not as reality is playing out in any regard; an asshole attempts to talk over your head. As I'm taking my time to respond to you in depth about what you post you are free to take it as you want, but I'm only stating what I know. If you have issue with what I post, be specific so I can address it. If you just take issue with what I say only because it doesn't jive with what you want; that's a personal problem. More to the point, I posted it up in public because I said I would, and hey, I did! More to the point you didn't voice any objections to it, so why bring it up? Seems like an attention whore thing to do.
There you go with that foot in your mouth again: You are arguing an engineering issue. IE; how does improperly mounting a tire effect the strength of the tire itself. You want numbers, will you understand the math behind those numbers? Will you be able to make an educated decision about stretching from that math? I dare say you won't if you don't understand the logic/science behind it. Again, I highly doubt you could talk over my head if you wanted to, but if you want, you're welcome to try. I am very able to live up to your requests of being an asshole, belittle you, smarter than you, and artificially inflate my ego. Just remember you stated these things before I ever started doing them.
Congratulations. Perhaps you should apply that knowledge here as you can easily simulate the tire as a series of circuits (again, look up spring-mass-damper systems).

Let me help you. The first sentence of that portion was directly to the first sentence in the one I quoted:
Nor have I intimated it as such.
I have stated that deforming a tire outside of manufactures spec prior to normal driving forces will weaken the tire. The difference is do you know how much weaker the tire has become? The obvious answer through your posts is of course, no; you do not.

Better? Now that I have that out of the way. Plastic deformation on a tire is always unsafe and can lead to failure. If you don't agree with that, I don't know if going over the very basics is going to help you. But continuing on...
See above clarification as I think you may be constructing a strawman.See above. I'm willing to help you understand, but as I already stated I'm not going to waste my time to do it for you.
Maybe, maybe not. Depends on the stretch now doesn't it (and more so to the point of this whole rabbit hole we're in)?
You mean like arithmetic? LOL (did you at least look up that definition before you posted?)
And I find it hard to believe you were able to figure out how to decline MENSA. See, this is what belittling feels like. Get used to it. You wanted it, remember? You're not helping your case much with these posts.
No, if I wanted to do that I'd waste my time and do the math myself, and then suffer through the same umbrage you present throughout this thread.
Lets look at what force is: F=ma, does it look like acceleration is a force? Is acceleration force? Nope. Sorry. Which I didn't see listed. Torque is not considered a force, but a force acting along a moment arm. An easy check is to look at the units. lbs, Newtons, are forces. ft-lbs, Newton-Meters are torques. These do play in to material mechanics but are usually derived out from the forces placed on the Free Body Diagram (FBD--which by the way I was attempting to get you to do). Nope, I'm just using the regular old mathematical definition of Force
You do realize that the force would be affecting the acceleration, or in other words if you draw a FBD with all the forces than acceleration is a byproduct of the calculation, but only matters if you're doing kinematics (which we are not) or inertial forces (which is currently outside your ball park).
Lol, I didn't criticize, I just stated what you posted was beyond the mark. Hey, look you said the same thing.Lets see, braking is a force as it works through friction, no? Acceleration still isn't a force. Sorry. Baby steps to understand the 3 dimensional issues. Guess what's after that... Heat addition. If you'd like, we can skip directly to 3D analysis with heat addition and embrittlement.

As I hit the post limit, here's the last point you raised:

:dunno: Will you understand the science and math behind it?

It was done old-school way...
One "owner" was an exec at the local Toyota dealership.
For shits and giggles, he brought out a brand new Tercel - very soft suspension with very tall tire profiles.
The autocross track was VERY rough and uneven - old airfield tarmac.

White shoe polish on the sidewall
Bump up the pressure until traction was OFF the sidewall
Nothing fancy

Us newbs were just horrified with how high the (hot) pressures were.
He comforted us saying that he's run tire pressures up to 80psi on very heavy Supras on the autocross course.
Scary...but you can't argue results.


-Ted

Please keep me out of your bullshit replies.
Until you learn how to comprehend properly, keep me out of it.
I NEVER said hippari stretch doesn't work - even though you seem to insist I did.
I'm against drift fanbois who call tire engineers idiots and dumbasses cause they can't run hippari stretch while the tire engineers don't recommend it.

Get it fuckin' right already.


-Ted

What your dealing with here is darwinism.

If these guys are willing jeopardize their contact point with the road, in which failure could lead to catastrophe at any speed over something that will help them slide if by the rare chance they ever attend a drift day or for the look of it, despite the advice of every tyre company/person that has a clue things will sort themselves out.

That's pretty neat. I by no means claim to be an expert on autox stuff so that just kinda threw me off for a huuuuuge loop. lmao Learn somethin' new every day I guess!

@Sofaking

There was no 80psi argument, I wasn't trying to argue, I was just stating that I've never heard of anything like that before, so it kinda blew my mind.

I bought a lazer/infared/however it works temp thingy but in the old days it was the shoe polish or the chalk method. Luckily today we have lower profile tires so the pressures don't need to be nearly as high

Honestly my fear is that they'll sort themselves out into a family vehicle. Not only killing/injuring themselves but doing likewise to that family.

Unless I'm mistaken, isn't that how Guitar Junkie(I think that's his name... I had just joined right after that happened) died/was killed?

This was my argument all along. Your conveluted subject changes and misdirection while pulling apart each sentence without reading the point of the post is what caused the argument. Notice how the original posts say that it WILL lead to failure (certainty) and this one said it CAN lead to failure (possibility). Without the math niether of us can be certain. But if it doesn't lead to failure I'm not sure how it's reasonable to argue it's unsafe.The failure rate of anything is 100% on a long enough timeline. If we don't define when its going to happen then to argue the safety of it is pointless.

Also for clarification, the whole science arguement that started wasn't by me. You felt the need to justify what you were saying by trying to bury me in science that I clearly didn't go to school for. I understand basic concepts of physics and how they apply in the world. I never argued that you weren't scientifically acurate to say that it's weaker, I only argued that nothing definitive about the safety concerns can be determined from the information except the single thing defined (weakness).

I don't feel a need to continue with you picking apart every word I say, but I would like some clarification in acceleration not being a force.
Acceleration changes the tire speed in relation to the ground, the direction of the tire (from a stop), and the shape of the tire through centrifugal force and friction with the pavement. Can you clarify why acceleration would not be a force? I'm sure you would break it down into different factors of acceleration, but as a broader term why would it not be right? It doesn't look as simple as placing it in Newton's second law because there are variables to rotation, but it still seems to apply to the description. I would think that if acceleration isn't a force then braking (the removal of rotation) would not be a force. Can you clarify please with a concise thought instead of breaking down each sentence?


@RETed, Sorry about that. I re-read your posts to be clear on your stance and it purely seems to be from a performance/style standpoint. I don't see anything arguing about it not being safe or not working. Clearly my argument with Vex got applied to more people than it should've. Again, sorry.

@Rotary, I wasn't saying it's an argument from the standpoint of being combative, just that it's something that I'm sure could be debated similarly to the stretch concept because it's out of specifications. Not picking sides or anything, I have no experience with over inflated tires to speak from.

Also, if you'd like to give a physics lesson I'm interested. I've made my point and am fine moving on non-combatively. If you'd like to continue with your point on the forces on a tire please do, I might learn something. I do understand more than you think, and I'm happy to learn more. Having me draw the diagram for your point doesn't make as much sense over the internet as if we were sitting in the same room (so you could more easily correct anything inaccurate), so if you'd like a diagram it probably would make more sense for you to create it.

Starting early are we, lets see if you address any of the points I've raised thus far.

(for review)
Then you dictated that I was belittling you. In all honesty I'm still waiting on those answers from page 3. Care to elaborate?

back to that list:
The list goes on and on, but you have yet to address those, so I'll leave it there for now.




Are you telling me there's tires that will not fail? Obviously not, so it still stands that all tires fail (certainty), as you have stated stretching a tire decreases the time or life of the failure, no? So back to what I said originally; Stretching a tire beyond manufacturers spec can and will cause it to fail. Do you know when or for that matter, if you're encroaching upon the plastic region of deformation of the compound? I've given you a simple test to verify if your specific stretch does, but you refuse to run the simple test that will give you the answer you're looking for. That's your issue. Not ours.
Actually, you don't need math to be certain. You need to understand the science to be certain, otherwise you will always wonder: "Did he just BS me, or did he just pull some number from somewhere?" So in all honesty would you be certain? Thank you for agreeing with me. Is a stretched tire going to fail before or after a properly mounted tire if they undergo the same driving conditions? How about if they hit a pot hole at speed, will they both have the same lifetime?Yes because you don't know when you're going to crash into a wall during a circuit so lets not worry about safety. I mean, seat belts, harnesses , helmets, barriers, they don't stop failure or for that matter know when failure will occur we must not need them. Again, logical fallacy to argue this point.

Oh... you didn't say:
What we've been discussing, and have been for ages is Material Science (which is an applied science, not theoretical). Your statements have been to the effect that unless I generate some random number everything I'm attempting to show you in science is just theory. Unfortunately I'm not that gullible, nor are a majority of the individuals on this board. Now continuing with your post...

Do you remember that little post about elastic and plastic deformation? By weaker, it means you have removed tensile strength from the tire. This translates to a closer proximity on the stress-strain curve to the yield (where plastic deformation begins), and thereby closer to the ultimate yield (where you have catastrophic failure). More to the point, as soon as you encroach upon the plastic region the tire is considered failed (in polymers it's whenever necking occurs in a test sample). Hence, weaker is not some arbitrary term you seem to think it is. It is scientific. It has value.

Be happy to oblige.
Acceleration, by itself, is not a force. If you look at the units of acceleration they are in terms of length per second per second (or second squared). Inertial forces can be derived by using acceleration, but must by definition be coupled with mass. Lets look at a very simple problem. Take a particle of finite mass traveling through space at a constant velocity (a=0). We now wish that particle to travel in some other direction. We therefore impart a force upon the body. At time=0 acceleration is still naught, though the force is applied, the change in direction has not occurred. As time progresses acceleration increases so long as that force is still applied (or in otherwords you have a constant force [lbs] causing an increase in acceleration [ft/s^2] over time)Acceleration is a derivative (as in derived from, not the mathematical operation, though it is that as well) of the forces. For instance; you will not apply an acceleration to a tire to get it to move. You can understand that the tire is accelerating, but the acceleration itself is not the cause. Using one of the previously discussed terms torque; the tire has a torque acting on the center of the hub. In other words you have a force acting through a moment arm which is then resulted into the tires acceleration.If you were using braking as a form of acceleration it would fall under the same as acceleration. I was personally using braking as another metric of force being applied to the brakes via friction which would impart a torque on the hub. Nope. But hopefully that helped.

The FBD is the basics of understanding an engineering problem. Being only concerned with 2 dimensions right now ensures that mistakes are easy to fix. Wiki has a decent article on it:

http://en.wikipedia.org/wiki/Free_body_diagram

You are very mistaken Vex. Dave (GuitarJunkie28) died because he lost control driving down a mountain road that he had driven since his teens and knew very well. It was a 4 lane road with no divider between opposing lanes. Those who knew him knew that he was not a reckless person, it was just a tragic accident. Interestingly enough, one of his tires was flat and very well could have been from a nail stuck in the road, but CHP did not go with this theory, instead stating that he just lost control around a curve. I find this hard to believe considering he knew the road, he knew his car, he wasn't a careless speed demon, and it wasn't wet or icy out.

The young woman that he hit made a full recovery and she was the only person in her car. I remember seeing her family at Dave's funeral. Fine people for sure.

Anyways just wanted to clear that up.

^that's terrible.

I don't feel the need to address a whole bunch of questions directed at a point I wasn't trying to make. I'll answer some though, I find that 1/2 of them are phrased in a sarcastic or rediculous nature because they're asking about things that were clarified in the topic already. The point wasn't if you could give me a million tests and contribute the rest of your life to the concern about tire safety. I was merely stating without said information which niether of us have, we can't determine a whole lot.

As for gauging proper inflation I concede, I don't know how to determine what it should be set at without feeling it out. I addressed that I fill them to 40psi, but I'm not sure what you want there. If you have an answer do share, if not... the question doesn't appear to have a point but to discredit my scientific process for determining proper tire inflation levels which I'm sure would also require math to determine anything specific.

I will offer a link to a tire that de-beaded for no apparent reason (or possibly someone deflated it). The thing is nothing can be proven in that field either without knowing 100% what all the variables are. I have personally had it happen for seemingly no reason... obviously there is a reason, but I don't know it so it's unexplained.
http://answers.yahoo.com/question/in...4221537AA4wUoh
Someone previously in this same topic even mentioned they've seen properly mounted tires debead if I remember correctly.

I did state that I believe you're arguing theory, I don't retract that. But I will happily clarify what I'm refering to. It's not the science you're quoting that I am calling theory. I'm arguing that the conclusion you've come to about the safety is your theory, your opinion, your conclusion. I made a graph to illustrate my point. I never said that your information on tire deformation was wrong or theory. I argued your conclusion of safety concern is jumping to a conclusion from the science and that's the part I wanted proven. Obviously when you change the shape of a material that was designed for a certain shape it will stress or break it. That's common knowledge.
http://carphotos.cardomain.com/ride_...4020_large.jpg

To state where on this graph you should plot a point of stretched sidewall failure would be only theory, speculation, guessing, whatever you care to call it without a pile of math that niether of us want to do, and only one of us knows the formulas (hint: not me).

As for your diagram...
http://carphotos.cardomain.com/ride_...4021_large.jpg
Is this what you want? teach away.

I don't want to be misunderstood, I was under the impression someone else hit him. Thank you for setting the record straight.

I haven't seen 'em answered but if you have a post number to refer me to I'll gladly re-read them.
Unfortunately what you describe isn't scientific. Tensile side wall strength is compromised with stretch.
During normal driving conditions?
Lets link two ideas here. Since you do not know how much air would be required to fill tire properly you do not know how the tire will be stressed. Underinflation will result in the previously posted picture. Overinflation will result in a blow out during normal operation. Couple that with the alteration in the geometry you now have points of stress along the tread and shoulder. The issue of a stretched tire can then be split to different points:

1. Failure due to underinflation or overinflation
2. Failure due to sidewall failure
3. Failure due to tread separation

Tensile strength of the sidewall affects the first two points. Since we're altering the geometry of the tire when it's stretched we can know by your own admission that:
Thereby removing factors of safety.

And I'm attempting to get you to understand the math so I'm not wasting my time. Additionally what tire would are you desiring?

Your forces are off. Displaced air is not needed and can be removed (unless we have lighter molecules than air). You're also missing a normal force (acts perpendicular to the tire) that keeps the tire from pushing through the ground.

That is all

I must say I LOATHE remixes, like when they say the same thing over and over again. I also hate when DJs mix a song on the radio, JUST LET ME HEAR THE FREAKIN SONG! lol

Therefore, I hate that video Brian. lol

I don't feel like going back and quoting, but everytime you asked for information about what I would like it was completely sarcastic and ended with you telling me that you didn't want to do the math. I got as specific as I was looking for and told you that you could use constants for variables if it made it easier. Your response was that you didn't want to waste your time. So quoting myself getting told that you aren't going to do it doesn't help. Move on to the physics lesson if you'd like to make a point, it's the closest thing to figuring anything out we've gotten to.
I already said that was your point... so if you're not adding anything what is the point in saying it again?
So you're saying that there is no possibility that the tire can sustain this, or you're just saying that you know a lot of factors determine the safety of a tire and without the math you can't do anything but speculate what may or may not happen?

Lets define for the sake of discussion that safety is the tire not failing (in any way) before the tread is used up during normal driving conditions. I understand it doesn't meet the original specifications, but the only information we know as of yet is that it will fail to the left side of my graph. Whether it gets even close to the green area is complete speculation.
I'm using a Falken Azenis RT615k 215/40-17 on a 17x9.5 wheel.
This was the point I was making about drawing the diagram and getting to the point. Going back and forth to prove you know where you're going with your point is a waste of both of our time.

oh yes, we hooked a smartphone up to someone's car audio back in Cali and blasted this when we pulled up next to Glenn on the street :rofl:

For the sake of moving this along...
http://carphotos.cardomain.com/ride_...4022_large.jpg

This is so retarded. I love it.

As soon as some mad tyte Affliction 4 Loco retard in a 240 with stretched tires crashes into me, I will have my lawyer/insurance absolutely destroy them based on the fact that the tires are incorrectly sized.

Then, this conversation will be over.

:ugh2:

:lol: :rofl:

Still not as bad as hearing my own balls slap and watching it on a big screen in a Vegas casino bar the night before my wedding. The people's reaction was classic once they figured out what the noise was. :rofl:

As long as they didn't realize who it actually was, everything should be ok :rofl: Should've had you lay some sack on my bumper while I was out there. Could've had Ty make a video called ball slapping turbo shooting sugargliders with RX7 turbo's and pissed off neighbors and recorded him doing the donuts in front of Kevins house and my block long burnout the time before the time I actually left :smilielol5:

I miss Cali, should've just left my car out there :lol:

Yeah dude, if we did that, your evil car would have probably cooperated. :lol:

You should have left it in Cali. You can always come back, I got 1500 square feet of workspace now. Also gonna be getting a used synchrowave, damn thing is water cooled, 100% duty cycle. Like Robert's mangina. :rofl:

I can't tell from how you drew the friction, does it have a direction? If it has a direction you need to apply either a torque or a force to the tire to dictate the impulse of motion (or the force enough to cancel out the 'amount' of friction acting on the tire to keep it from moving). If the tire is static (which would be easier) you have drawn the FBD correctly.

Sorry didn't see this until just now.
Using variables in this sort of math will cause you to get a bunch of variables in equations that do not make much sense. We'll use constants sure enough, but leaving variables into the equations of question is going to be worse than just using real values.

This isn't physics in the true sense of the word (at least not from when I took those classes). This is basic material science.
It seemed to me that you were attempting to sustain this as scientific procedure. If you're no longer sustaining that or if I misinterpreted that from your post then by all means the point is moot now.
This may better help you understand: Factor of Safety. A reduction in the FOS reduces the ability for the tire to handle the same stresses as a properly mounted tire would otherwise be able to endure.
I think this is a failure to communicate what FOS is.
Again, I think you miss the point. Discussing the science isn't for my benefit but yours. If you do not understand where the number comes from at the end of the day all it's going to be to you is a number--But if you understand where that number came from at the end of the day you will know and understand what the material is doing when you stretch the tire and place it under load.

Since I clearly don't understand how to apply a torque to offer a direction because I thought it could be used as a force I wouldn't know how to add it. For the sake of this analysis lets say the tire is static.

I read the FoS link, interesting stuff. To my knowledge (making an assumption without taking hours of classes on the subject)... Passenger tires would have an MoS of +3 or +4 if the sidewall lasts 3-4 times longer than the predicted load, correct? Not to mention that any given tire usually isn't at its maximum load when installed on a passenger vehicle anyway (Which is what the FoS is engineered to. I.E. max inflation pressure/weight), correct?

Also the article covered a sentence on my point as well...
This would lead me to believe that it is possible I am right. I'm not saying that it is or isn't "safe". I'm saying that it's possible that it is safe, correct? If it is possible that it is safe, then the obvious conclusion would be that it would not be a fact to call it "unsafe", correct?