That's certainly possible; I misunderstand people on occasion; so let's review:
The OP asked a question about a tire he had removed a screw from that wasn't leaking. He was concerned that it might begin leaking. He received advice ranging from:
to:
Opinions both, and not dissimilar from other advice one might find on an internet forum.
I came down on the position that:
Note that this opinion in no way contradicted your post:
Someone else gave an opinion that only a "patch" type repair is acceptable (but also sounded like they said if it wasn't leaking leave it alone.):
I have been told elsewhere (sometimes by tire engineers) that plugs won't work in general and specifically won't work on radials because:
I don't agree with the general premise that modern plugs don't work or that patches are always superior, regardless of belting type or tire construction. So I burned some internet bandwidth talking about my personal experiences with tire repairs, tire repair shops and tire manufacturing companies and basically said 3 things:
1. An internal tire repair (e.g. patch) is technically difficult to do correctly.
2. My personal observations and experience with plugs does not indicate they are more prone to failure, in fact the success rate is probably higher when taking typical tire repair "technician" skill into account.
3. Given *my* evaluations of tire failures, while any damage to a tire may contribute to tire failure, I didn't see that the presence of a plug type repair was a significant cause of catastrophic (i.e. "sudden" or "blowout" see quotes above) tire failure.
Your response was:
Which reads an awful lot like you're saying, while repairs of any kind are relatively cheap compared to a new tire, unless the new tire costs more than someone's life you should replace the tire.
Of course you go on to add:
This is written apparently to protect the readership lest anyone actually follow my stupid advice or believe my misguided stories. (Which as a statistical matter may actually be in alignment with about 99% of the tire repair advice you'll get from commercial tire operations.)
You go on (at length) to describe your fleet experience with a company that used plugs as a repair method and develop some "statistics" based on a mechanics' anecdotal data on plug repair failures. You then extrapolate failure rate data to suggest plugs fail about 10% of the time. Even though you discredit this already shaky statistic ( shaky due to the fact that your "data" isn't actually "data" but somebody's recollection of past events) in the middle of your story:
Well, I'll put my story and experience up against some third party report of a one-in-ten failure rate that was blamed on a bad batch of plugs any day of the week.
As you mentioned, you like the "Point/Counterpoint" format and:
and:
So I will try to ask some questions and make observations that maybe some of us can learn from along the way:
1. The statistic on plug failures
is not useful unless better repair population data is known and failure modes are separated for special causes (e.g. bad batch of plugs or other reasons). If I ask some guy I know about how many UFO's he's seen or how many times he's been abducted, are you prepared to accept this "data" as proof of some hypothesis I may hold? Why is your data source more inherently reliable than any person that may or may not remember what he had for breakfast two weeks ago?
2. If we were somehow able to clean up your "data" and prove some failure rate on a large enough population of plug repairs; how would that data be useful to the general public without observations on alternate repair populations (cold patching, hot patching) and at least a token control group of tires that had no repairs? Let's pretend the failure rate on plugs is 10%, on what basis do you propose that say, cold or hot patching is lower, the same, or higher?
3. While it's fine to self identify as an expert in a wide range of technical specialties (I'm sure we all do from time to time) when rebutting someone's opinion that they have presented as opinion based on experience, you may want to consider using "Better Data" to make said rebuttal. Particularly if you are as boorish as to state a particular poster is "not in a position" to state their opinion on a particular matter.
I think I can state, based on your postings, that you either haven't studied statistics and statistically valid observations of products and processes, or you flunked the class and have been operating on "opinion" and "anecdotal" data as a "Tire Engineer". That's nothing to be particularly ashamed of, I see it all the time in industry; it just happens to be worst among "experts".
It also doesn't mean you can't give your "title" and state your opinion. In spite of your lack of observation and DOE skills, you may actually know something. If you are what you say you are, I would like to know your opinions.
But don't think that just because you are a self-identified expert, that people like me are going to wilt away because you've got some story to tell, from some guy you know, that had something happen, and that supports your pet theory.
The basic flaw in your analysis is that you can't tell the difference between Opinion based roughly on undocumented experience, and Fact that is statistically verifiable with real data. This is compounded by the belief that as a self-identified expert your "opinion" should count more for some reason because it is your opinion.
Have "we" learned anything yet? Let me summarize:
1. For some reason you took exception to the opinions I posted and stated I wasn't qualified to state my opinions. I basically blew it off and quoted your own post in support of my hypothesis that tire geeks and salesmen tend to tell you to buy a new tire no matter what happens because it's just not worth the risk to repair or use a "damaged" tire. I still think I'm on pretty solid ground on that point.
2. You then propose that I must have misunderstood you and go on to quote anecdotal data that you then extrapolate into a failure rate for plug repairs. Besides the fact your data collection methods and statistical analysis would earn you an "F" in a statistics (FMEA, MEOST, DOE, SPC) 101 class, you seem to think your little story proves...something.
What exactly I misunderstood is still unclear; you say you know of a situation (involving defective plugs) that somebody thinks they remember resulted in a 10% failure rate. That proves, *what*? That you *don't* recommend replacement for all damaged tires? Just for the reading audience, what is your recommended course of action for dealing with a flat tire?
Here’s a tip: You log on here and post your opinions and I’ll respect that and post my opinions and I may even post hard data if it exists to support my positions. You do the same (and learn the difference between opinion and data based fact) and I won’t feel compelled to tarnish your image as a Tire Engineer by pointing out your obvious lack of skill in data collection and analysis; not to mention people skills.
