On 07/19/2017 12:00 AM, Mad Roger wrote:
What's the *performance* difference between 15 inch, 16 inch and 17 inch
tires (all else being equal)?

Let's say that the stock wheel is 16 inch and let's ignore sheer looks, and
the fact the speedometer will read differently, and let's ignore obvious
non-performance wheel-well fitment issue since they're obviously not
performance changes.

What *performance* changes will the one inch larger or smaller tire cause?

Basically, I'm wondering why people almost universally want larger wheels,
where all I'm asking about are what the performance tradeoffs are.


Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

On Wed, 19 Jul 2017 11:06:54 -0600,
rbowman wrote:

Basically, I'm wondering why people almost universally want larger wheels,
where all I'm asking about are what the performance tradeoffs are.


Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

The psychological problem I'm having with "bling" with respect to race cars
is that there seem to be zero performance benefits of larger wheels, even
for race cars.

What race car benefits from 25% less torque at the driving wheel contact
patch for example?

On 7/19/2017 10:50 AM, Mad Roger wrote:
On Wed, 19 Jul 2017 11:06:54 -0600,
rbowman wrote:

Basically, I'm wondering why people almost universally want larger wheels,
where all I'm asking about are what the performance tradeoffs are.


Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

The psychological problem I'm having with "bling" with respect to race cars
is that there seem to be zero performance benefits of larger wheels, even
for race cars.

What race car benefits from 25% less torque at the driving wheel contact
patch for example?


They change the gear ratio, eliminating the difference. Jeeeze!

And that 25% difference is going from a 15" to a 19" wheel, and
similarly larger tire diameter. Who does that without changing the gearing?

On Wed, 19 Jul 2017 11:28:11 -0700,
Bob F wrote:

They change the gear ratio, eliminating the difference. Jeeeze!

And that 25% difference is going from a 15" to a 19" wheel, and
similarly larger tire diameter. Who does that without changing the gearing?

Thank you for pointing out my error of the 25% loss in torque being from
only a 1 inch change.

I misinterpreted the Ed Pawlowski article.
https://www.carthrottle.com/post/how...t-performance/

The 25% loss of torque came with a four inch change in diameter!

But it's still a loss in torque.
The Car and Driver article said the fuel mileage suffered also.

Effects of Upsized Wheels and Tires Tested
http://www.caranddriver.com/features...d-tires-tested

"What's immediately apparent from the results is that as the wheel-and-tire
packages get larger and heavier, acceleration and fuel economy suffer.
Neither is a huge surprise, but we measured a 10-percent drop in fuel
economy and a four-percent degradation in 0-to-60-mph acceleration from the
15s to the 19s"

rbowman posted for all of us...



On 07/19/2017 12:00 AM, Mad Roger wrote:
What's the *performance* difference between 15 inch, 16 inch and 17 inch
tires (all else being equal)?

Let's say that the stock wheel is 16 inch and let's ignore sheer looks, and
the fact the speedometer will read differently, and let's ignore obvious
non-performance wheel-well fitment issue since they're obviously not
performance changes.

What *performance* changes will the one inch larger or smaller tire cause?

Basically, I'm wondering why people almost universally want larger wheels,
where all I'm asking about are what the performance tradeoffs are.


Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

I think this guy is the same argumentative/troll about weight weights and
Horror fright bead breakers, etc. He just changed hosts.

--
Tekkie

On 7/19/2017 12:18 PM, Mad Roger wrote:
On Wed, 19 Jul 2017 11:28:11 -0700,
Bob F wrote:

They change the gear ratio, eliminating the difference. Jeeeze!

And that 25% difference is going from a 15" to a 19" wheel, and
similarly larger tire diameter. Who does that without changing the gearing?

Thank you for pointing out my error of the 25% loss in torque being from
only a 1 inch change.

I misinterpreted the Ed Pawlowski article.
https://www.carthrottle.com/post/how...t-performance/

The 25% loss of torque came with a four inch change in diameter!

But it's still a loss in torque.
The Car and Driver article said the fuel mileage suffered also.

Effects of Upsized Wheels and Tires Tested
http://www.caranddriver.com/features...d-tires-tested

"What's immediately apparent from the results is that as the wheel-and-tire
packages get larger and heavier, acceleration and fuel economy suffer.
Neither is a huge surprise, but we measured a 10-percent drop in fuel
economy and a four-percent degradation in 0-to-60-mph acceleration from the
15s to the 19s"


But of course, that fuel economy was based on odometer readings, which
are reading 26% low with the 19" tires. And the acceleration was only
slightly different because only the 1st gear part of the acceleration is
going to be changed much. After that, the gears keep the engine near
it's optimal power range for acceleration. On the highway, the engine
will be operating at 26% lower RPM, so depending on the power curve of
the engine, mileage could go either way.

On 07/19/2017 11:50 AM, Mad Roger wrote:
The psychological problem I'm having with "bling" with respect to race cars
is that there seem to be zero performance benefits of larger wheels, even
for race cars.

Bling and performance have no correlation. Race cars generally have to
meet specifications. For example NASCAR calls for 15" steel wheels. F1
is even more restrictive. The wheels RE 13" and all tires are supplied
by Pirelli. Pirelli has several different models based on stiffness,
wet/ dry, and so forth but they're all Pirelli. At one time Bridgestone
was in but they were dropped. I don't know why. IndyCars run Firestone
on 15" wheels.

I'm curious what race cars run 17/18/19" wheels.

On Wednesday, July 19, 2017 at 3:58:17 PM UTC-4, Bob F wrote:
On 7/19/2017 12:18 PM, Mad Roger wrote:
On Wed, 19 Jul 2017 11:28:11 -0700,
Bob F wrote:

They change the gear ratio, eliminating the difference. Jeeeze!

And that 25% difference is going from a 15" to a 19" wheel, and
similarly larger tire diameter. Who does that without changing the gearing?

Thank you for pointing out my error of the 25% loss in torque being from
only a 1 inch change.

I misinterpreted the Ed Pawlowski article.
https://www.carthrottle.com/post/how...t-performance/

The 25% loss of torque came with a four inch change in diameter!

But it's still a loss in torque.
The Car and Driver article said the fuel mileage suffered also.

Effects of Upsized Wheels and Tires Tested
http://www.caranddriver.com/features...d-tires-tested

"What's immediately apparent from the results is that as the wheel-and-tire
packages get larger and heavier, acceleration and fuel economy suffer.
Neither is a huge surprise, but we measured a 10-percent drop in fuel
economy and a four-percent degradation in 0-to-60-mph acceleration from the
15s to the 19s"


But of course, that fuel economy was based on odometer readings, which
are reading 26% low with the 19" tires.

I would give Car and Driver credit for accounting for that in their
testing. What;s also interesting is that they made a 4" change in
diameter and saw only a 4% decrease in acceleration, which is very
different than what was claimed in that other article, where there
was huge alleged difference in acceleration with just a 1" change.

On Wednesday, July 19, 2017 at 3:19:01 PM UTC-4, Tekkie® wrote:
rbowman posted for all of us...



On 07/19/2017 12:00 AM, Mad Roger wrote:
What's the *performance* difference between 15 inch, 16 inch and 17 inch
tires (all else being equal)?

Let's say that the stock wheel is 16 inch and let's ignore sheer looks, and
the fact the speedometer will read differently, and let's ignore obvious
non-performance wheel-well fitment issue since they're obviously not
performance changes.

What *performance* changes will the one inch larger or smaller tire cause?

Basically, I'm wondering why people almost universally want larger wheels,
where all I'm asking about are what the performance tradeoffs are.


Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

I think this guy is the same argumentative/troll about weight weights and
Horror fright bead breakers, etc. He just changed hosts.

--
Tekkie

Stifle yourself! I made one sarcastic remark to the poster, after about
6 exchanges where he's going in circles, and I was accused of being nasty
to everyone on the internet!

On Wed, 19 Jul 2017 13:57:54 -0700 (PDT), trader_4
wrote:


I think this guy is the same argumentative/troll about weight weights and
Horror fright bead breakers, etc. He just changed hosts.

--
Tekkie

Stifle yourself! I made one sarcastic remark to the poster, after about
6 exchanges where he's going in circles, and I was accused of being nasty
to everyone on the internet!

Not the Internet son, "Usenet". Do you not know the difference?

On Wed, 19 Jul 2017 13:57:54 -0700 (PDT), trader_4
wrote:

Stifle yourself!

ROFL - "Stifle", who dug up Carroll O'Connor and gave him access to
Usenet?

"Stifle yourself Edith, dummy up"

- Carroll O'Connor as Archie Bunker, All in the Family, 1971 - 1979

On Wed, 19 Jul 2017 17:50:17 -0000 (UTC), Mad Roger
wrote:

On Wed, 19 Jul 2017 11:06:54 -0600,
rbowman wrote:

Basically, I'm wondering why people almost universally want larger wheels,
where all I'm asking about are what the performance tradeoffs are.


Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

The psychological problem I'm having with "bling" with respect to race cars
is that there seem to be zero performance benefits of larger wheels, even
for race cars.

What race car benefits from 25% less torque at the driving wheel contact
patch for example?
When it has 1000 plus horsepower to the rear wheels, that decrease in
torque CAN mean he doesn't burn the tires off as easily - and on a
drag car, the tire diameter can be adjusted to get the car to launch
better, and to top out it's speed at the right point on the track

On Wed, 19 Jul 2017 11:28:11 -0700, Bob F wrote:

On 7/19/2017 10:50 AM, Mad Roger wrote:
On Wed, 19 Jul 2017 11:06:54 -0600,
rbowman wrote:

Basically, I'm wondering why people almost universally want larger wheels,
where all I'm asking about are what the performance tradeoffs are.


Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

The psychological problem I'm having with "bling" with respect to race cars
is that there seem to be zero performance benefits of larger wheels, even
for race cars.

What race car benefits from 25% less torque at the driving wheel contact
patch for example?


They change the gear ratio, eliminating the difference. Jeeeze!

And that 25% difference is going from a 15" to a 19" wheel, and
similarly larger tire diameter. Who does that without changing the gearing?
"tuner kids"

On Wed, 19 Jul 2017 12:53:25 -0700, Bob F wrote:

On 7/19/2017 12:18 PM, Mad Roger wrote:
On Wed, 19 Jul 2017 11:28:11 -0700,
Bob F wrote:

They change the gear ratio, eliminating the difference. Jeeeze!

And that 25% difference is going from a 15" to a 19" wheel, and
similarly larger tire diameter. Who does that without changing the gearing?

Thank you for pointing out my error of the 25% loss in torque being from
only a 1 inch change.

I misinterpreted the Ed Pawlowski article.
https://www.carthrottle.com/post/how...t-performance/

The 25% loss of torque came with a four inch change in diameter!

But it's still a loss in torque.
The Car and Driver article said the fuel mileage suffered also.

Effects of Upsized Wheels and Tires Tested
http://www.caranddriver.com/features...d-tires-tested

"What's immediately apparent from the results is that as the wheel-and-tire
packages get larger and heavier, acceleration and fuel economy suffer.
Neither is a huge surprise, but we measured a 10-percent drop in fuel
economy and a four-percent degradation in 0-to-60-mph acceleration from the
15s to the 19s"


But of course, that fuel economy was based on odometer readings, which
are reading 26% low with the 19" tires. And the acceleration was only
slightly different because only the 1st gear part of the acceleration is
going to be changed much. After that, the gears keep the engine near
it's optimal power range for acceleration. On the highway, the engine
will be operating at 26% lower RPM, so depending on the power curve of
the engine, mileage could go either way.
I REALLY doubt it was "uncorrected" data, and the shiftpoints need
to be reprogrammed (if it is an automatic) or shift points changed by
the driver to optimize either mileage or accelleration. It is NOT a
simple calculation to determine which way mileage will go, or how to
drive the modified vehicle for best results.

On Wed, 19 Jul 2017 19:36:21 -0400,
wrote:

But of course, that fuel economy was based on odometer readings, which
are reading 26% low with the 19" tires. And the acceleration was only
slightly different because only the 1st gear part of the acceleration is
going to be changed much. After that, the gears keep the engine near
it's optimal power range for acceleration. On the highway, the engine
will be operating at 26% lower RPM, so depending on the power curve of
the engine, mileage could go either way.
I REALLY doubt it was "uncorrected" data, and the shiftpoints need
to be reprogrammed (if it is an automatic) or shift points changed by
the driver to optimize either mileage or accelleration. It is NOT a
simple calculation to determine which way mileage will go, or how to
drive the modified vehicle for best results.

I don't know how Car & Driver compensated for the things you guys talk
about, but what I find interesting is that they were not in the least
surprised that they had a relatively huge decrease in MPG when they ran
their tests.

Seems like they were not expecting an increase in MPG, that's for sure.

On Wed, 19 Jul 2017 12:53:25 -0700,
Bob F wrote:

But of course, that fuel economy was based on odometer readings, which
are reading 26% low with the 19" tires. And the acceleration was only
slightly different because only the 1st gear part of the acceleration is
going to be changed much. After that, the gears keep the engine near
it's optimal power range for acceleration. On the highway, the engine
will be operating at 26% lower RPM, so depending on the power curve of
the engine, mileage could go either way.

Even worse, it could be argued that "standard methods" of calculating mpg
are off by a factor of about a mile per gallon either way, which means
that, say, 20mph is anywhere from 19mpg to 21mpg.

Certainly anyone who calculates mpg with decimal places is ignoring sig
figs in their measurement capabilities in that nobody does a reliable test
loop (and even those who do, in Austin Texas for example, get sig figs not
much better than that).

WARNING: I have to look up if challenged the actual reliability but I
"assume" that most people think their measurements are infinitely more
accurate and repeatable than they really are. If it's not as big as +1 and
-1 mpg accuracy, it's not that far off. Certainly there is no decimal place
in typical mpg calculations by a consumer.

On Wed, 19 Jul 2017 11:06:54 -0600,
rbowman wrote:

Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

I searched for that thread.

Is it this one?
Why 20" wheels, by Micky, May 8, 2017
https://groups.google.com/forum/#!to...ZxvM%5B1-25%5D

If so, I'll read it to see if there was more accurate information there
than here.

On Thu, 20 Jul 2017 02:13:30 -0000 (UTC), Mad Roger
wrote:

On Wed, 19 Jul 2017 11:06:54 -0600,
rbowman wrote:

Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

I searched for that thread.

Is it this one?
Why 20" wheels, by Micky, May 8, 2017
https://groups.google.com/forum/#!to...ZxvM%5B1-25%5D

If so, I'll read it to see if there was more accurate information there
than here.
Nothing of value there.

On 07/19/2017 01:53 PM, Bob F wrote:

But of course, that fuel economy was based on odometer readings, which
are reading 26% low with the 19" tires.

That would be a real half-assed test. It's not rocket science. Japanese
bikes are notoriously inaccurate for both speed and odometer so I use a
GPS. Harley's, strange to say, tend to be quite accurate. Unfortunately
the LED display on mine is getting hard to read unless it's hot out so I
use a $20 Sigma bicycle computer. Measure the rolling circumference of
the tire, program the computer, check it with a GPS, and you're good to go.

On 07/19/2017 07:45 PM, Mad Roger wrote:
WARNING: I have to look up if challenged the actual reliability but I
"assume" that most people think their measurements are infinitely more
accurate and repeatable than they really are. If it's not as big as +1 and
-1 mpg accuracy, it's not that far off. Certainly there is no decimal place
in typical mpg calculations by a consumer.

I use a Scangauge II plugged into the OBDII port. It's sort of accurate

On 07/19/2017 08:13 PM, Mad Roger wrote:
On Wed, 19 Jul 2017 11:06:54 -0600,
rbowman wrote:

Bling. This topic was beaten to death a month or two ago. When someone
says larger diameter wheels must be effective because they are used on
race cars ask them what size wheels are mandated for F1 or NASCAR and
what sort of racing they had in mind outside of the Fast & Furious
franchise.

I searched for that thread.

Is it this one?
Why 20" wheels, by Micky, May 8, 2017
https://groups.google.com/forum/#!to...ZxvM%5B1-25%5D

If so, I'll read it to see if there was more accurate information there
than here.


Don't bother. There was more bull**** in that thread than in a feedlot.

On Wed, 19 Jul 2017 23:08:20 -0600,
rbowman wrote:

I searched for that thread.

Is it this one?
Why 20" wheels, by Micky, May 8, 2017
https://groups.google.com/forum/#!to...ZxvM%5B1-25%5D

If so, I'll read it to see if there was more accurate information there
than here.


Don't bother. There was more bull**** in that thread than in a feedlot.

Thanks. By now you can tell that I care about two things:
+ I have an "opinion" about everything, but I don't trust my opinion, so,
+ I try to get facts that either support or contradict that opinion.
If those facts are reliable, I change my opinion.

My original opinion was that there was a performance benefit to
larger-diameter fitments, but my new opinion is based on the facts
unearthed in this thread, which is that you'd be hard pressed to gain the
one known performance advantage, which is to put the engine into a sweeter
spot on the torque curve.

However, even if you did that, there are many other factors, the
next-biggest of which is the contact patch, but there are others such as
the weight change, materials change, suspension change, etc.

Hence, larger fitments have, essentially, no performance advantage and most
likely have a negative effect on performance overall in most cases.

If anyone has data that contradicts that opinion, I'm all ears.

On Wed, 19 Jul 2017 22:36:21 -0600,
rbowman wrote:

I use a Scangauge II plugged into the OBDII port. It's sort of accurate

I'm still looking for where I got that 4% accuracy figure for mpg
calculations.

This article describes the two-part problem correctly but the article
doesn't put a percentage on the results calculated at home.
How accurate are gas mileage monitors?
http://electronics.howstuffworks.com...ge-monitor.htm
"If your car's mileage varies by about 10 percent based on driving
conditions, how do you know if the improvement you see after, say, adding
acetone to your gas tank is a result of the additive or of the weather?"

Basically, everyone who gives you a MPG claim is wrong (IMHO) because they
actually *believe* their accuracy and repeatability to figures which are,
in reality, a figement of their imagination.

Sure, they can *see* the decimal places, but it's my current statement that
I need to prove that anyone quoting numbers within + or - 1 mpg is probably
fooled by lack of knowledge about what they're actually doing.

The two areas of huge inaccuracy a
a. The test conditions
b. The test equipment

I'll check out these references which are in the back of the article.
Allen, Mike. "3 Gadgets That Really Work." Popular Mechanics. DIY Auto.
December
2008.http://www.popularmechanics.com/auto...23.html?page=2
Allen, Mike. "How to Monitor Your Fuel Economy in Real Time on the Road."
Popular Mechanics. June 9,
2008.http://www.popularmechanics.com/auto...o/4267957.html

On 07/20/2017 05:59 AM, Mad Roger wrote:
I'll check out these references which are in the back of the article.
Allen, Mike. "3 Gadgets That Really Work." Popular Mechanics. DIY Auto.
December
2008.http://www.popularmechanics.com/auto...23.html?page=2
Allen, Mike. "How to Monitor Your Fuel Economy in Real Time on the Road."
Popular Mechanics. June 9,
2008.http://www.popularmechanics.com/auto...o/4267957.html

That link didn't work for me but

http://www.popularmechanics.com/cars...12057/4267957/

appears to be the same article.

"There are some tech tricks you can use to help monitor your fuel
economy as you drive. I'm fooling around with a couple of devices right
now. I just installed a Scangauge on my motorcycle. This $180 device
plugs into the On Board Diagnostic System (OBD II) port under the dash
of virtually any post-1996 car or light truck. It operates as a scan
tool (much more on that here), so it gives me trouble codes and
streaming data, but it also works as an electronic gauge cluster and
trip computer. I can track battery voltage, coolant temp and sundry
while tooling down the interstate. But one feature is invaluable: the
instantaneous fuel economy readout. It gets fuel quantity data from the
injection timing--the longer the injectors are open, the more fuel they
squirt. It's amazingly accurate, too."

The ScanGauge can be calibrated for the actual rolling circumference of
the tires. It does instantaneous, which I don't find to useful, as well
as daily or tank mileage reporting. On a fillup it predicts the gallons
you will put in. That's the least accurate because I always use the
automatic shutoff but even that is usually within a couple of tenths of
a gallon.

Using the car odometer and a notebook with your gas purchases is
strictly for the Luddites. It's like measuring acceleration with a stop
watch and the seat of your pants when you can use an accelerometer.

On 07/20/2017 05:59 AM, Mad Roger wrote:
Hence, larger fitments have, essentially, no performance advantage and most
likely have a negative effect on performance overall in most cases.

But they look kewl... There is a similar phenomenon with motorcycles.
The first thing many Harley owners do is replace the stock exhaust with
aftermarket pipes. While they've gotten better at hiding it, the OEM
exhaust has a cross over between the two pipes that people find
unappealing. The new pipes may have less restriction and be louder. They
may be shinier. In most cases they also result in a slight reduction in
power. Most of the people aren't doing baseline dyno runs and retesting
after modifications. They are buying bling and working on the intuition
that more noise == less back pressure == more power.

On Thu, 20 Jul 2017 09:02:15 -0600,
rbowman wrote:

Hence, larger fitments have, essentially, no performance advantage and most
likely have a negative effect on performance overall in most cases.

But they look kewl...

Yup. We agree.

Putting an M3 badge on an otherwise 3-series bimmer makes it look faster
too!

And, whitewall tires look kewl to some, where nobody thinks that there's an
inherent performance benefit (I hope!).

There is a similar phenomenon with motorcycles.
The first thing many Harley owners do is replace the stock exhaust with
aftermarket pipes. While they've gotten better at hiding it, the OEM
exhaust has a cross over between the two pipes that people find
unappealing. ]

Interesting.
The whole point of exhaust pipes on a motorcycle are, I would assume
+ Get the hot gas out the bike without burning the rider (or the bike)
+ Get it out fast without hindering the engine HP to push it out
+ Keep the sound to a "sane" level (as determined by all within earshot)
+ Look ok to the buyer of the bike (e.g., shiny things look good to fish)

My problem with bike "sounds" is that the potato-potato-potato sound isn't
so much an issue with me as is the presumably child-like psychology of
someone whose pipes are unreasonably loud.

Why?
Do they need attention *that* badly and can't get it any way else?

Please note that I am not a psychologist so take my quick psychoanalysis of
the loud-pipe crowd with a grain of salt and some humor.

The new pipes may have less restriction and be louder. They
may be shinier. In most cases they also result in a slight reduction in
power. Most of the people aren't doing baseline dyno runs and retesting
after modifications. They are buying bling and working on the intuition
that more noise == less back pressure == more power.

Understood completely.
It's sad, but loud pipes exist, so, there must be a *lot* of people working
on those same (probably scientifically flawed) assumptions.

In a very real way, the loud pipes = more power argument stands on the same
fundamentals that the bigger wheels = more performance argument.

Sure, you can get it - but you'd be hard pressed to beat the manufacturer
in most cases, and even if you did - there are almost always engineering
(aka scientific) cons for every pro.

For example, why not just get rid of the pipes altogether?
Then you'd have the least resistance (although no tuning) of the air
outflow from the engine.

I guess the argument is that would be too loud (but some pipes I hear
riding past my house, which is on a busy street, seem *that* loud!).

On Thu, 20 Jul 2017 08:29:53 -0600,
rbowman wrote:

Using the car odometer and a notebook with your gas purchases is
strictly for the Luddites. It's like measuring acceleration with a stop
watch and the seat of your pants when you can use an accelerometer.

Thanks for checking out the articles because they were ancillary to our
conversation on tire-diameter effects on performance, but it's an
interesting question so there's now a new thread opened to iron it out.

What is the realistic accuracy & precision of typical consumer MPG
calculations (tripmeter miles/pump gallons)
https://groups.google.com/forum/#!to...ir/PT3YdPClM7g

My contention is, at the start anyway, that it's going to be really bad for
the people who love decimal places - but - let's see how it turns out
scientifically because I don't want to make unfounded claims without
stating their foundation realistically.

On Thursday, July 20, 2017 at 2:13:58 PM UTC-4, Mad Roger wrote:
On Thu, 20 Jul 2017 09:02:15 -0600,
rbowman wrote:

Hence, larger fitments have, essentially, no performance advantage and most
likely have a negative effect on performance overall in most cases.

But they look kewl...

Yup. We agree.

Putting an M3 badge on an otherwise 3-series bimmer makes it look faster
too!

And, whitewall tires look kewl to some, where nobody thinks that there's an
inherent performance benefit (I hope!).

There is a similar phenomenon with motorcycles.
The first thing many Harley owners do is replace the stock exhaust with
aftermarket pipes. While they've gotten better at hiding it, the OEM
exhaust has a cross over between the two pipes that people find
unappealing. ]

Interesting.
The whole point of exhaust pipes on a motorcycle are, I would assume
+ Get the hot gas out the bike without burning the rider (or the bike)
+ Get it out fast without hindering the engine HP to push it out
+ Keep the sound to a "sane" level (as determined by all within earshot)
+ Look ok to the buyer of the bike (e.g., shiny things look good to fish)

My problem with bike "sounds" is that the potato-potato-potato sound isn't
so much an issue with me as is the presumably child-like psychology of
someone whose pipes are unreasonably loud.

Why?
Do they need attention *that* badly and can't get it any way else?

Please note that I am not a psychologist so take my quick psychoanalysis of
the loud-pipe crowd with a grain of salt and some humor.

The new pipes may have less restriction and be louder. They
may be shinier. In most cases they also result in a slight reduction in
power. Most of the people aren't doing baseline dyno runs and retesting
after modifications. They are buying bling and working on the intuition
that more noise == less back pressure == more power.

Understood completely.
It's sad, but loud pipes exist, so, there must be a *lot* of people working
on those same (probably scientifically flawed) assumptions.

In a very real way, the loud pipes = more power argument stands on the same
fundamentals that the bigger wheels = more performance argument.

I think like with wheels you'll find that most people aren't
doing it for the power. They like louder pipes because they
sound cool. There is also the saying that loud pipes save lives.
I don't know if that's true or not, but it seems logical that
drawing attention to the fact that a MC is there, is a benefit,
because most of the car and bike accidents occur when the car
driver for whatever reasons, behaved like the bike never registered
in their mind.






Sure, you can get it - but you'd be hard pressed to beat the manufacturer
in most cases, and even if you did - there are almost always engineering
(aka scientific) cons for every pro.

For example, why not just get rid of the pipes altogether?
Then you'd have the least resistance (although no tuning) of the air
outflow from the engine.

I guess the argument is that would be too loud (but some pipes I hear
riding past my house, which is on a busy street, seem *that* loud!).

That's probably because they are straight pipes. A MC normally
has not only pipes, but mufflers.

On Thu, 20 Jul 2017 18:13:54 -0000 (UTC), Mad Roger
wrote:

On Thu, 20 Jul 2017 09:02:15 -0600,
rbowman wrote:

Hence, larger fitments have, essentially, no performance advantage and most
likely have a negative effect on performance overall in most cases.

But they look kewl...

Yup. We agree.

Putting an M3 badge on an otherwise 3-series bimmer makes it look faster
too!

And, whitewall tires look kewl to some, where nobody thinks that there's an
inherent performance benefit (I hope!).

There is a similar phenomenon with motorcycles.
The first thing many Harley owners do is replace the stock exhaust with
aftermarket pipes. While they've gotten better at hiding it, the OEM
exhaust has a cross over between the two pipes that people find
unappealing. ]

Interesting.
The whole point of exhaust pipes on a motorcycle are, I would assume
+ Get the hot gas out the bike without burning the rider (or the bike)
+ Get it out fast without hindering the engine HP to push it out
+ Keep the sound to a "sane" level (as determined by all within earshot)
+ Look ok to the buyer of the bike (e.g., shiny things look good to fish)

My problem with bike "sounds" is that the potato-potato-potato sound isn't
so much an issue with me as is the presumably child-like psychology of
someone whose pipes are unreasonably loud.

Why?
Do they need attention *that* badly and can't get it any way else?

Please note that I am not a psychologist so take my quick psychoanalysis of
the loud-pipe crowd with a grain of salt and some humor.

The new pipes may have less restriction and be louder. They
may be shinier. In most cases they also result in a slight reduction in
power. Most of the people aren't doing baseline dyno runs and retesting
after modifications. They are buying bling and working on the intuition
that more noise == less back pressure == more power.

Understood completely.
It's sad, but loud pipes exist, so, there must be a *lot* of people working
on those same (probably scientifically flawed) assumptions.

In a very real way, the loud pipes = more power argument stands on the same
fundamentals that the bigger wheels = more performance argument.

Sure, you can get it - but you'd be hard pressed to beat the manufacturer
in most cases, and even if you did - there are almost always engineering
(aka scientific) cons for every pro.

For example, why not just get rid of the pipes altogether?
Then you'd have the least resistance (although no tuning) of the air
outflow from the engine.

I guess the argument is that would be too loud (but some pipes I hear
riding past my house, which is on a busy street, seem *that* loud!).
A good friend of mine designed and built pipes for bikes and formula
cars - and believe me, a good pipe can make a LOT more power - but it
can also be pretty quiet - and a lot of loud pipes waste more power
making noise than turning wheels.

On Thu, 20 Jul 2017 17:30:49 -0400,
wrote:

A good friend of mine designed and built pipes for bikes and formula
cars - and believe me, a good pipe can make a LOT more power - but it
can also be pretty quiet - and a lot of loud pipes waste more power
making noise than turning wheels.

I'm not gonna agree with you 'cuz that gets me into trouble.

On Thu, 20 Jul 2017 12:10:52 -0700 (PDT),
trader_4 wrote:

There is also the saying that loud pipes save lives.

Looking up the most common types of fatal motorcycle accidents, it seems
that cars almost never rear end a motorcycle (5%).

About three quarters of the fatal accidents occur as head-on collisions,
with the other quarter being mostly the motorclists losing control of their
bike on their own.

Half of the accidents are when cars turn left into the motorcyclist.
http://www.nolo.com/legal-encycloped...ses-30330.html

There's nothing there about loud pipes but obviously visibility is always a
critical factor.

If you look at common causes of crashes, almost none of them would be
avoided by loud pipes (e.g., losing control of the bike).
https://www.bestmotorbikejackets.com...cle-accidents/

I don't know if that's true or not, but it seems logical that
drawing attention to the fact that a MC is there, is a benefit,
because most of the car and bike accidents occur when the car
driver for whatever reasons, behaved like the bike never registered
in their mind.

I did a quick skim of the common types of motorcycle accidents
http://www.mackesysmye.com/articles-...ycle-accidents
https://www.habbaspilaw.com/5-common...cle-accidents/

Where most, if not almost all of them, wouldn't make any difference with or
without loud pipes. Given that light moves faster and further than sound
(so to speak), one has to wonder if someone doesn't "see" you coming the
other way (which is the most common and most dangerous crash), are they
really going to hear you while they're in their luxurious cage?

Doubt it.
But I'm open to research that says otherwise.

It's interesting that I looked at about a dozen articles, almost all of
which suggested how to avoid the accidents, where none suggested loud
pipes.
https://rideapart.com/articles/10-co...-to-avoid-them

Of course, there are plenty of articles titled
"Do loud pipes save lives"
https://motorbikewriter.com/challeng...-pipes-theory/
http://motorcyclesafetynews.com/?p=878
http://motorcycleintelligence.com/do...ve-lives/1119/
https://www.autoevolution.com/news/m...t-1-45969.html

Yikes! Look at just that *last* article.
"The truth behind such a claim disproves this myth on so many levels:
simple, common physics, common sense or plain reason can bring in countless
reasons because this is just a myth. Let's tread the path of physics a bit
and analyze what's happening from a strictly mechanical point of view."

You can read them, but I skimmed them, with the result being it's a myth.

On Thursday, July 20, 2017 at 8:14:37 PM UTC-4, Mad Roger wrote:
On Thu, 20 Jul 2017 12:10:52 -0700 (PDT),
trader_4 wrote:

There is also the saying that loud pipes save lives.

Looking up the most common types of fatal motorcycle accidents, it seems
that cars almost never rear end a motorcycle (5%).

About three quarters of the fatal accidents occur as head-on collisions,
with the other quarter being mostly the motorclists losing control of their
bike on their own.

Half of the accidents are when cars turn left into the motorcyclist.
http://www.nolo.com/legal-encycloped...ses-30330.html


There's nothing there about loud pipes but obviously visibility is always a
critical factor.


Did you really expect there to be something about loud pipes?
The only way you'd find that was if there was an actual study.




If you look at common causes of crashes, almost none of them would be
avoided by loud pipes (e.g., losing control of the bike).
https://www.bestmotorbikejackets.com...cle-accidents/


Yet you just said that half of all accidents occur with cars turning
in front of bikes. If the bike is loud, it seems that there is a
better chance the car driver might notice it coming, from 100 ft
ahead, instead of turning
in front of it. That happens very frequently, a car is waiting to
make a turn, a bike is coming in the opposing lane, and they just turn
in front of it anyway, as if the bike did not register with their brain.




I don't know if that's true or not, but it seems logical that
drawing attention to the fact that a MC is there, is a benefit,
because most of the car and bike accidents occur when the car
driver for whatever reasons, behaved like the bike never registered
in their mind.

I did a quick skim of the common types of motorcycle accidents
http://www.mackesysmye.com/articles-...ycle-accidents
https://www.habbaspilaw.com/5-common...cle-accidents/

Where most, if not almost all of them, wouldn't make any difference with or
without loud pipes.

Give it up already. Don't you have anything better to do?
Now your trying to read tea leaves. You don;t have any valid
data to even begin to work with.


Given that light moves faster and further than sound
(so to speak), one has to wonder if someone doesn't "see" you coming the
other way (which is the most common and most dangerous crash), are they
really going to hear you while they're in their luxurious cage?

Doubt it.

Well then let;s remove the sirens from emergency vehicles and just
go with the lights.


But I'm open to research that says otherwise.

It's interesting that I looked at about a dozen articles, almost all of
which suggested how to avoid the accidents, where none suggested loud
pipes.

Good grief.



https://rideapart.com/articles/10-co...-to-avoid-them

Of course, there are plenty of articles titled
"Do loud pipes save lives"
https://motorbikewriter.com/challeng...-pipes-theory/
http://motorcyclesafetynews.com/?p=878
http://motorcycleintelligence.com/do...ve-lives/1119/
https://www.autoevolution.com/news/m...t-1-45969.html

Yikes! Look at just that *last* article.
"The truth behind such a claim disproves this myth on so many levels:
simple, common physics,

Yeah, and you know all about physics, right? So tell us by what
physics are you able to determine that a noisy bike isn't more
noticeable to others than a quiet bike?

From idiots like this:


"With the air/ gas jest directed towards the rear of the bike, it's there where all the noise goes. "

Who should I believe, that idiot or my own ears. Sure more of the noise
will go behind the bike, but anyone who's been around a hog coming at
them on the road knows that you can hear those loud pipes coming at you.
Sirens would be of no use on emergency vehicles if that were the case.
In fact, what we again know from physics is that this guy is an idiot.
What you actually have is the doppler shift. There would be no doppler
shift from a noisy vehicle coming towards you, only silence if the
above BS was true.

What you have there are pure opinion pieces, laced with factual BS.
You're one of the sad cases that thinks whatever they find on the internet
on some jazzed up websites must be true because someone posted an
article. Yet when someone tries to explain the actual physics to you,
like I did in the earlier part of this thread, you just ignore it and
go on to the next fluff piece. Sure, you're a "scientist". ROFL


common sense or plain reason can bring in countless
reasons because this is just a myth.

How far did your common sense and intuition get you in the earlier
part, about wheel size and torque and work/energy?



Let's tread the path of physics a bit
and analyze what's happening from a strictly mechanical point of view."

You can read them, but I skimmed them, with the result being it's a myth.

It would be nice if you were a myth.

On Thu, 20 Jul 2017 18:34:32 -0700 (PDT),
trader_4 wrote:

Did you really expect there to be something about loud pipes?

The physics of loud pipes saves lives shows it to be a myth.
https://www.autoevolution.com/news/m...t-1-45969.html

The only way you'd find that was if there was an actual study.

"I almost broke Google looking for a large-scale, objective, scientifically
conducted, peer-reviewed study showing that users of loud pipes have a
lower mortality rate compared to other motorcyclists."
http://www.motorcyclistonline.com/3-...-that-wont-die

"On the surface it seems obvious that the noise emitted by loud motorcycle
exhaust systems would aid in conspicuity and cause more watchful driving by
other motorists. Yet not a single thoughtful study has been done that
supports the theory."
http://www.noiseoff.org/pipes/

See also numerous articles on "Do loud pipes save lives"...
https://motorbikewriter.com/challeng...-pipes-theory/
http://motorcyclesafetynews.com/?p=878
http://motorcycleintelligence.com/do...ve-lives/1119/
http://www.huffingtonpost.com/2016/0...n_9518206.html
http://www.straight.com/life/loud-pi...-riders-safety
http://tucson.com/news/opinion/colum...f975d8564.html
http://noiseoff.org/pipes/foreword.php
http://www.motorcyclecruiser.com/12-...misconceptions

On 07/20/2017 12:13 PM, Mad Roger wrote:
For example, why not just get rid of the pipes altogether?
Then you'd have the least resistance (although no tuning) of the air
outflow from the engine.

I guess the argument is that would be too loud (but some pipes I hear
riding past my house, which is on a busy street, seem *that* loud!).

And you probably wouldn't have much scavenging of the cylinder either.
Best case you have a very low pressure node at the right place in the
exhaust plumbing. The problem with that is it tends toward a narrow
power band, hence the two strokes 'coming on to the pipe'.

We won't even go into rejetting the carb for older bikes or
reprogramming the profile for FI bikes now that you've changed the flow
characteristics.

On 07/20/2017 06:14 PM, Mad Roger wrote:
You can read them, but I skimmed them, with the result being it's a myth.

No argument. When you ride the best approach is to consider your fellow
motorists to be utter assholes who, if not outright homicidal, do not
see or hear bikes.

Loud pipes have one good use. When you're stopped at a light next to
some soccer mom yapping on her cell phone revving it up to 5000 rpm
might ruin her conversation for a bit.

On Thursday, July 20, 2017 at 9:57:20 PM UTC-4, Mad Roger wrote:
On Thu, 20 Jul 2017 18:34:32 -0700 (PDT),
trader_4 wrote:

Did you really expect there to be something about loud pipes?

The physics of loud pipes saves lives shows it to be a myth.
https://www.autoevolution.com/news/m...t-1-45969.html

The only way you'd find that was if there was an actual study.

"I almost broke Google looking for a large-scale, objective, scientifically
conducted, peer-reviewed study showing that users of loud pipes have a
lower mortality rate compared to other motorcyclists."
http://www.motorcyclistonline.com/3-...-that-wont-die

"On the surface it seems obvious that the noise emitted by loud motorcycle
exhaust systems would aid in conspicuity and cause more watchful driving by
other motorists. Yet not a single thoughtful study has been done that
supports the theory."
http://www.noiseoff.org/pipes/

See also numerous articles on "Do loud pipes save lives"...
https://motorbikewriter.com/challeng...-pipes-theory/
http://motorcyclesafetynews.com/?p=878
http://motorcycleintelligence.com/do...ve-lives/1119/
http://www.huffingtonpost.com/2016/0...n_9518206.html
http://www.straight.com/life/loud-pi...-riders-safety
http://tucson.com/news/opinion/colum...f975d8564.html
http://noiseoff.org/pipes/foreword.php
http://www.motorcyclecruiser.com/12-...misconceptions

Like I said, you don't understand the difference between an actual
study and opinion pieces. You take anything anyone puts up on a
website as "data", even when it's obviously just opinion. Yet when
someone takes the time to explain the physics of something to you,
like I did with that whole endless BS about torque and work/energy,
you just ignore it, don't even comment on it and it's off to the next
internet fluff piece, which you treat as gospel.

On Thu, 20 Jul 2017 19:43:54 -0700 (PDT),
trader_4 wrote:

Like I said, you don't understand the difference between an actual
study and opinion pieces. You take anything anyone puts up on a
website as "data", even when it's obviously just opinion. Yet when
someone takes the time to explain the physics of something to you,
like I did with that whole endless BS about torque and work/energy,
you just ignore it, don't even comment on it and it's off to the next
internet fluff piece, which you treat as gospel.

What part of your brain didn't get the two direct quotes that clearly
stated that there are no scientifically objective studies to be found?

In fact, you missed both quotes - even though they were the *only* quotes
in the prior post.

And both said exactly what you said.

I can't even *agree* with you, without you vehemently disagreeing with me.

Methinks there's something personal here on your side, but not on mine.

On Fri, 21 Jul 2017 03:04:39 -0000 (UTC), Mad Roger
wrote:

On Thu, 20 Jul 2017 19:43:54 -0700 (PDT),
trader_4 wrote:

Like I said, you don't understand the difference between an actual
study and opinion pieces. You take anything anyone puts up on a
website as "data", even when it's obviously just opinion. Yet when
someone takes the time to explain the physics of something to you,
like I did with that whole endless BS about torque and work/energy,
you just ignore it, don't even comment on it and it's off to the next
internet fluff piece, which you treat as gospel.

What part of your brain didn't get the two direct quotes that clearly
stated that there are no scientifically objective studies to be found?

In fact, you missed both quotes - even though they were the *only* quotes
in the prior post.

And both said exactly what you said.

I can't even *agree* with you, without you vehemently disagreeing with me.

Methinks there's something personal here on your side, but not on mine.
With Trader it's always personal - which is why he's in my bin.

On Thursday, July 20, 2017 at 11:04:43 PM UTC-4, Mad Roger wrote:
On Thu, 20 Jul 2017 19:43:54 -0700 (PDT),
trader_4 wrote:

Like I said, you don't understand the difference between an actual
study and opinion pieces. You take anything anyone puts up on a
website as "data", even when it's obviously just opinion. Yet when
someone takes the time to explain the physics of something to you,
like I did with that whole endless BS about torque and work/energy,
you just ignore it, don't even comment on it and it's off to the next
internet fluff piece, which you treat as gospel.

What part of your brain didn't get the two direct quotes that clearly
stated that there are no scientifically objective studies to be found?

The part that saw that you didn't stop there, you went on to cite
pure opinion pieces one after the other, as if they were gospel.
Including totally stupid ones that claim that *all noise* from loud
pipes goes rearward, not forward. You think that because someone posts
something on a website, that it;s automatically meaningful, even when
it contains total discrediting stupidity like the above.





In fact, you missed both quotes - even though they were the *only* quotes
in the prior post.

And both said exactly what you said.

I can't even *agree* with you, without you vehemently disagreeing with me.

Methinks there's something personal here on your side, but not on mine.

What I think is that while claiming to be a scientist, you clearly
are clueless when it comes to even the most basic science and scientific
methods. Nor do you show any inclination to learn, ie you just totally
ignored it when I immediately pointed out the most basic physics that
even a child would seek to understand. Instead, it's off to find fluff
pieces on the internet.

On Thursday, July 20, 2017 at 11:40:42 PM UTC-4, wrote:
On Fri, 21 Jul 2017 03:04:39 -0000 (UTC), Mad Roger
wrote:

On Thu, 20 Jul 2017 19:43:54 -0700 (PDT),
trader_4 wrote:

Like I said, you don't understand the difference between an actual
study and opinion pieces. You take anything anyone puts up on a
website as "data", even when it's obviously just opinion. Yet when
someone takes the time to explain the physics of something to you,
like I did with that whole endless BS about torque and work/energy,
you just ignore it, don't even comment on it and it's off to the next
internet fluff piece, which you treat as gospel.

What part of your brain didn't get the two direct quotes that clearly
stated that there are no scientifically objective studies to be found?

In fact, you missed both quotes - even though they were the *only* quotes
in the prior post.

And both said exactly what you said.

I can't even *agree* with you, without you vehemently disagreeing with me.

Methinks there's something personal here on your side, but not on mine.
With Trader it's always personal - which is why he's in my bin.

Clare, you're just sore because so many of us have taken you to the
woodshed for all the stupid and incorrect things you've posted here,
especially on electrical issues. Doug Miller hasn't been here in
awhile, but boy he;s got your number too and has called you out
on your BS many times. And I don't just come out of the woodwork and
attack you either. Sure, if I disagree with something you post,
then I;ll say so. But when I agree with what you post, I don't just
sit there like an asshole and take shots at you. Both Bob F and I
were on the same page here, on the same side, as you from the beginning.
And I haven't blocked you either, that's the last refuge of idiots
that aren't man enough to be challenged and defend themselves.
It also leads to perpetual ignorance. Now, like I said, why don't
you go get a room with your new buddy and jerk each other off some
more.