Drifting, hellaflush, slammed, tire stretch blog/bash thread.

[sofaking]

Originally Posted by vex

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.

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.

Originally Posted by vex

(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.)

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:

Originally Posted by vex

Posts aren't deleted, they're just in the process of moving to a more appropriate section. I'll respond to your critiques there.

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

Originally Posted by vex

Sidewall deformation caused by stretching not only results in premature tire failure, but also eliminates the speed rating as viable metric to ensure safety of the car.

Page 3

Originally Posted by vex

a family dies because you used your predictable vehicle behavior to slam into them

Page 4

Originally Posted by vex

I stated that it's not wise, and would prove detrimental to the tire.

Page 5

Originally Posted by vex

So what you're saying is that you're willing to sacrifice factors of safety for deforming a tire and putting strain on the shoulder that is not normally there. Thereby negating entirely the built in factors of safety which the company determined prior to construction.

Those 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.

[vex]

Originally Posted by sofaking

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.

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).

Sidewall deformation caused by stretching not only results in premature tire failure, but also eliminates the speed rating as viable metric to ensure safety of the car.

This you agreed with when you stated:

Meanwhile arguing with no facts about the science of it besides making it "weaker" doesn't prove anything. 1% weaker is nothing, 500% weaker is huge. No numbers are being discussed.

and from a tire company itself:

Mounting a tire on the incorrect size rim could be dangerous and a safety issue. We strongly discourage it.

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.

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:

Lol, mathematic proofs are not obscure in any sense of the word. But from your link:

1.
evidence sufficient to establish a thing as true, or to produce belief in its truth.
2.
anything serving as such evidence: What proof do you have?
3.
the act of testing or making trial of anything; test; trial: to put a thing to the proof.
4.
the establishment of the truth of anything; demonstration.
5.
Law . (in judicial proceedings) evidence having probative weight.
6.
the effect of evidence in convincing the mind.
7.
an arithmetical operation serving to check the correctness of a calculation.
8.
Mathematics, Logic . a sequence of steps, statements, or demonstrations that leads to a valid conclusion.
9.
a test to determine the quality, durability, etc., of materials used in manufacture.
10.
Distilling .
a.
the arbitrary standard strength, as of an alcoholic liquor.
b.
strength with reference to this standard: “100 proof” signifies a proof spirit, usually 50% alcohol.
11.
Photography . a trial print from a negative.
12.
Printing .
a.
a trial impression, as of composed type, taken to correct errors and make alterations.
b.
one of a number of early and superior impressions taken before the printing of the ordinary issue: to pull a proof.
13.
(in printmaking) an impression taken from a plate or the like to show the quality or condition of work during the process of execution; a print pulled for examination while working on a plate, block, stone, etc.
14.
Numismatics . one of a limited number of coins of a new issue struck from polished dies on a blank having a polished or matte surface.
15.
the state of having been tested and approved.
16.
proved strength, as of armor.
17.
Scots Law . the trial of a case by a judge alone, without a jury.
–adjective
18.
able to withstand; successful in not being overcome: proof against temptation.
19.
impenetrable, impervious, or invulnerable: proof against outside temperature changes.
20.
used for testing or proving; serving as proof.
21.
of standard strength, as an alcoholic liquor.
22.
of tested or proven strength or quality: proof armor.
23.
noting pieces of pure gold and silver that the U.S. assay and mint offices use as standards.
–verb (used with object)
24.
to test; examine for flaws, errors, etc.; check against a standard or standards.
25.
Printing . prove ( def. 7 ) .
26.
to proofread.
27.
to treat or coat for the purpose of rendering resistant to deterioration, damage, etc. (often used in combination): to proof a house against termites; to shrink-proof a shirt.
28.
Cookery .
a.
to test the effectiveness of (yeast), as by combining with warm water so that a bubbling action occurs.
b.
to cause (esp. bread dough) to rise due to the addition of baker's yeast or other leavening.

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 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.

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.

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.

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.

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.

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).

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...

Let me help you. The first sentence of that portion was directly to the first sentence in the one I quoted:

I really can't understand why it's so hard to admit that mathematics is required to prove your point.

Nor have I intimated it as such.

Without it the only thing that you can say for a fact is that the tire is weaker, weaker =/= failure or unsafe.

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...

Those are all verifiable proof (definition 2) that you stated that it's unsafe and will prematurely fail.

See above clarification as I think you may be constructing a strawman.

Now provide proof (definition 7) that the sidewall failure will happen before the tread, or remove the premise that it's unsafe.

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.

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.

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)?

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.

You mean like arithmetic? LOL (did you at least look up that definition before you posted?)

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.

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?

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)

You're not helping your case much with these posts.

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.

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.

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?

Lets look at what force is: F=ma, does it look like acceleration is a force? Is acceleration force? Nope. Sorry.

Centrifugal force?

Which I didn't see listed.

Torque?

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).

These things appear to be forces to me unless we're using an obscure definition of force.

Nope, I'm just using the regular old mathematical definition of Force

I'm using 12a, which one are you using?
http://dictionary.reference.com/browse/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).

Answering beyond what you asked for recieves much criticism as I expected from replying to just what you said.

Lol, I didn't criticize, I just stated what you posted was beyond the mark. Hey, look you said the same thing.

Fuck yourself, you think as an engineer that acceleration isn't force on a tire yet braking is?

Lets see, braking is a force as it works through friction, no? Acceleration still isn't a force. Sorry.

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[sic] of a 3 dimentional[sic] object.

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.

[vex]

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

Hopefully we can skip to that too.

Will you understand the science and math behind it?

[RETed]

Originally Posted by Rotary no Densetsu

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.

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

[RETed]

Originally Posted by sofaking

@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.

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

[Mazdabater]

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.

[Rotary no Densetsu]

Originally Posted by RETed

It was done old-school way...
-snip-

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.

[TitaniumTT]

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

[vex]

Originally Posted by Mazdabater

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.

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?

[sofaking]

Originally Posted by vex

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.

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.

a force is any influence that causes a free body to undergo a change in speed, a change in direction, or a change in shape.

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.

[sofaking]

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.

[vex]

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

(for review)

And completely negates the speed rating of the tire. Sidewall deformation caused by stretching not only results in premature tire failure, but also eliminates the speed rating as viable metric to ensure safety of the car.

Stretching the tire really has no benefit beyond aesthetics (but last I checked cars were meant to be driven).

On the contrary, see the above quotes from installers and individuals in the business. Even if they tell you it's bad and you insist upon it being mounted, and a family dies because you used your predictable vehicle behavior to slam into them, who's going to take the heat for all those who died? You? Or are you going to let the buck go to the individual that broke the law in mounting your tire?

Do you really want me to get the information I already posted from a tire designer to prove you have altered the tire dynamics to no benefit?

Just out of curiousity as the geometry is deformed, tire pressure is altered (maximum tire pressure--do you still put in the recommended amount, are you eyeballing it, or some other means outside of manufacturers spec)?--With due respect, you answered this by stating you eyeballed it.

Furthermore stretching tires can run aground upon other design features such as Michelin's Stress Equilibrium Casings

What do you mean by technical data? How much tire defelction is altered during a specific corner? Would you like it arranged by contact patch size, wheel size, or some other metric? You seem to demand specifics but be purpously obtuse when it comes to defining the metrics.

Would you like to see acceleration data, lap times, or some other metric? If you have an idea of what you want, I'm sure I can hunt it down for everyone to see. Beyond what I have already posted, what specifically do you have issue with? Is something stated that is not accurate or correct? If so, what is it and why?

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:

What data do you want? Do you want the proper PSI for tire inflation with modified geometry, or would you like something else?

Actually I have never heard of a properly mounted and inflated tire ever breaking the bead without a structural defect manifesting itself. But since this is your allegation, find me a documented incident where one such occurred.

Which begs the question, how do you gage proper inflation when you deform the sidewall that much? You do not fill it to factory spec. What metric do you use to fill it or are you just filling it 'till it's "that'll do?" For all you have shown, you could be driving with it under inflated or over inflated and you wouldn't know would you? You're guessing on something that you have no data on. If you have data on proper pressure filling on deformed sidewall tires then I suggest you enlighten us on how the tensile strength of the sidewall is accounted for.

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

Originally Posted by sofaking

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).

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.

Without the math niether of us can be certain.

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?

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.

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?

If we don't define when its going to happen then to argue the safety of it is pointless.

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.

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.

Oh... you didn't say:

You're dealing with concepts not application, that's theory.

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...

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).

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.

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.

Be happy to oblige.

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?

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.

I'm sure you would break it down into different factors of acceleration, but as a broader term why would it not be right?

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)

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.

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.

I would think that if acceleration isn't a force then braking (the removal of rotation) would not be a force.

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.

Can you clarify please with a concise thought instead of breaking down each sentence?

Nope. But hopefully that helped.

[vex]

Originally Posted by sofaking

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.

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

[mazpower]

Originally Posted by vex

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?

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.

[sofaking]

^that's terrible.