Do cyclists make better motorcyclists?

wrote:
On Thu, 2 Sep 2004 11:39:45 -0700, "Tom Nakashima"
wrote:



wrote in message
. ..

On Thu, 2 Sep 2004 07:33:13 -0700, "Tom Nakashima"

Yes, Mark, one who understands motorcycling.
Here's another link on a motorcycle slide bike course that one can enroll
in.
http://www.motorcycle.com/mo/mccustom/slide.html
-tom


Dear Tom,

The page seems to suggest only rear-wheel power slides
exiting paved corners.

The apparatus appears to be designed to prevent the
motorcycle rider from falling down if he exceeds the limits
of traction.

Am I mistaken?

Carl Fogel

Yes Carl Fogel that is correct,
the lean slide bike apparatus is to keep the rider from falling down,
however it not only suggest power sliding the rear wheel, but the front
wheel also slides as well. I actually spoke with a motorcycle rider
(co-worker) this morning who took the Keith Code course here at SLAC, the
rear tire, as well as the front tire does slide in the corners with the
control of the throttle. The front not as much as the rear. He also said
your gauge for your limits of slide and lean angle is your knee touching the
ground. Did you also read about the paragraph about controlled slide?
Are you convinced now? Maybe you should take the Keith Code course
yourself if you're still not convinced.
-tom


Dear Tom,

Well, no, to be frank, I'm not convinced that racers are
cornering so hard on pavement that their front tires lose
traction and slide.

The word "slide" might be a bit imprecise. However, wide
tires rolling under high lateral force do exhibit what is
known as a slip angle, caused as the rubber deforms as it
rolls through the contact patch. This action of the rubber
"walking" or "squirming" laterally makes the wheel act as if
slipping sideways as it rolled.


http://www.msgroup.org/TIP076.html


What path would a motorcycle or bicycle follow if the front
tire began to slide sideways under hard cornering?

On a motorcycle, riders describe the feeling as "understeer"
or "oversteer" (depending on which tire is slipping more),
causing the path of the motorcycle to turn at a greater or
less radius, respectively, than the steering angle would
indicate.

The contact patch of a bicycle tire isn't large or wide
enough to exhibit any significant slip angle. Under hard
cornering, a bicycle either tracks exactly as the steering
angle requires, or the tire slides out and the rider falls.

Mark McMaster

On Sat, 04 Sep 2004 03:34:01 GMT, Mark McMaster
wrote:

wrote:
On Thu, 2 Sep 2004 11:39:45 -0700, "Tom Nakashima"
wrote:



wrote in message
...

On Thu, 2 Sep 2004 07:33:13 -0700, "Tom Nakashima"

Yes, Mark, one who understands motorcycling.
Here's another link on a motorcycle slide bike course that one can enroll
in.
http://www.motorcycle.com/mo/mccustom/slide.html
-tom


Dear Tom,

The page seems to suggest only rear-wheel power slides
exiting paved corners.

The apparatus appears to be designed to prevent the
motorcycle rider from falling down if he exceeds the limits
of traction.

Am I mistaken?

Carl Fogel

Yes Carl Fogel that is correct,
the lean slide bike apparatus is to keep the rider from falling down,
however it not only suggest power sliding the rear wheel, but the front
wheel also slides as well. I actually spoke with a motorcycle rider
(co-worker) this morning who took the Keith Code course here at SLAC, the
rear tire, as well as the front tire does slide in the corners with the
control of the throttle. The front not as much as the rear. He also said
your gauge for your limits of slide and lean angle is your knee touching the
ground. Did you also read about the paragraph about controlled slide?
Are you convinced now? Maybe you should take the Keith Code course
yourself if you're still not convinced.
-tom


Dear Tom,

Well, no, to be frank, I'm not convinced that racers are
cornering so hard on pavement that their front tires lose
traction and slide.

The word "slide" might be a bit imprecise. However, wide
tires rolling under high lateral force do exhibit what is
known as a slip angle, caused as the rubber deforms as it
rolls through the contact patch. This action of the rubber
"walking" or "squirming" laterally makes the wheel act as if
slipping sideways as it rolled.


http://www.msgroup.org/TIP076.html


What path would a motorcycle or bicycle follow if the front
tire began to slide sideways under hard cornering?

On a motorcycle, riders describe the feeling as "understeer"
or "oversteer" (depending on which tire is slipping more),
causing the path of the motorcycle to turn at a greater or
less radius, respectively, than the steering angle would
indicate.

The contact patch of a bicycle tire isn't large or wide
enough to exhibit any significant slip angle. Under hard
cornering, a bicycle either tracks exactly as the steering
angle requires, or the tire slides out and the rider falls.

Mark McMaster


Dear Mark and Tom,

I could squirm (pun intended) about which tire the page
describes as slipping more, but I think that it would be
better to say that the slip (versus slide) is close enough
to "a wee bit" to convince me that Tom has a reasonable
point and that I was wrong enough that I need to say so.

Thanks for sticking with your point, Tom.

And thanks for clearing that up, Mark.

Carl Fogel

On Sat, 04 Sep 2004 03:34:01 GMT, Mark McMaster
wrote:

wrote:
On Thu, 2 Sep 2004 11:39:45 -0700, "Tom Nakashima"
wrote:



wrote in message
...

On Thu, 2 Sep 2004 07:33:13 -0700, "Tom Nakashima"

Yes, Mark, one who understands motorcycling.
Here's another link on a motorcycle slide bike course that one can enroll
in.
http://www.motorcycle.com/mo/mccustom/slide.html
-tom


Dear Tom,

The page seems to suggest only rear-wheel power slides
exiting paved corners.

The apparatus appears to be designed to prevent the
motorcycle rider from falling down if he exceeds the limits
of traction.

Am I mistaken?

Carl Fogel

Yes Carl Fogel that is correct,
the lean slide bike apparatus is to keep the rider from falling down,
however it not only suggest power sliding the rear wheel, but the front
wheel also slides as well. I actually spoke with a motorcycle rider
(co-worker) this morning who took the Keith Code course here at SLAC, the
rear tire, as well as the front tire does slide in the corners with the
control of the throttle. The front not as much as the rear. He also said
your gauge for your limits of slide and lean angle is your knee touching the
ground. Did you also read about the paragraph about controlled slide?
Are you convinced now? Maybe you should take the Keith Code course
yourself if you're still not convinced.
-tom


Dear Tom,

Well, no, to be frank, I'm not convinced that racers are
cornering so hard on pavement that their front tires lose
traction and slide.

The word "slide" might be a bit imprecise. However, wide
tires rolling under high lateral force do exhibit what is
known as a slip angle, caused as the rubber deforms as it
rolls through the contact patch. This action of the rubber
"walking" or "squirming" laterally makes the wheel act as if
slipping sideways as it rolled.


http://www.msgroup.org/TIP076.html


What path would a motorcycle or bicycle follow if the front
tire began to slide sideways under hard cornering?

On a motorcycle, riders describe the feeling as "understeer"
or "oversteer" (depending on which tire is slipping more),
causing the path of the motorcycle to turn at a greater or
less radius, respectively, than the steering angle would
indicate.

The contact patch of a bicycle tire isn't large or wide
enough to exhibit any significant slip angle. Under hard
cornering, a bicycle either tracks exactly as the steering
angle requires, or the tire slides out and the rider falls.

Mark McMaster


Dear Mark and Tom,

I could squirm (pun intended) about which tire the page
describes as slipping more, but I think that it would be
better to say that the slip (versus slide) is close enough
to "a wee bit" to convince me that Tom has a reasonable
point and that I was wrong enough that I need to say so.

Thanks for sticking with your point, Tom.

And thanks for clearing that up, Mark.

Carl Fogel

wrote in message
...
On Fri, 3 Sep 2004 19:52:23 +0100, "Trevor"
wrote:


wrote in message ...

Now I'm truly baffled. I was assuming that you meant the
tiny side road off the A494 running up from Bwlch-y-parc
toward Moel Ethinen.

Originally, you estimated a significant stretch of 10%
grade.

Are you saying that the A494 has a 10% grade somewhere
around Moel Ethinen and that you were pedalling 70 mph down
it?

I'm hard pressed to find a drop of a hundred meters on the
unfortunately crowded topo map in several kilometers on the
A494 around Moel Ethinen--and that stretch ends in a
180-degree hairpin into Llanbedr-Dyffryn-Clwd.


Other way 9kms. turn around, read my post, Gwernymynydd believed to be
1:10 not steep for these parts.

Trevor

Dear Trevor,

Here's Gwernymynydd with the A494 running through it:

http://www.streetmap.co.uk/newmap.sr...v=321500,36250
0&st=4&ar=N&mapp=newmap.srf&searchp=newsearch.srf& dn=616

or

http://tinyurl.com/5tdz3

Is this is where you're hitting 70 mph with the help of a 15
mph tailwind and a 10% grade that is not considered steep
for paved roads in this part of Wales?

The contour lines are 10 meters and the map is 3000 meters
wide. While the map is badly cluttered, the rise from the
roundabout to the east to "PH" in the center appears to be
on the order of 60 meters in 1200, rather closer to a
5%.grade.

That'll be the bit I refer to as tapering out. The steeper section is the
1km to the west of Gwernymynydd crossroads and reading from an 1:50 000
sheet the 10m contour lines are less than 2mm apart making the grade steeper
than 1 in 10 The crossroads also contain traffic lights (mostly) ;-} I'll
try for a larger scale, I could then measure steepest grade with greatest
accuracy. What are you disputing?

Trevor

wrote in message
...
On Fri, 3 Sep 2004 19:52:23 +0100, "Trevor"
wrote:


wrote in message ...

Now I'm truly baffled. I was assuming that you meant the
tiny side road off the A494 running up from Bwlch-y-parc
toward Moel Ethinen.

Originally, you estimated a significant stretch of 10%
grade.

Are you saying that the A494 has a 10% grade somewhere
around Moel Ethinen and that you were pedalling 70 mph down
it?

I'm hard pressed to find a drop of a hundred meters on the
unfortunately crowded topo map in several kilometers on the
A494 around Moel Ethinen--and that stretch ends in a
180-degree hairpin into Llanbedr-Dyffryn-Clwd.


Other way 9kms. turn around, read my post, Gwernymynydd believed to be
1:10 not steep for these parts.

Trevor

Dear Trevor,

Here's Gwernymynydd with the A494 running through it:

http://www.streetmap.co.uk/newmap.sr...v=321500,36250
0&st=4&ar=N&mapp=newmap.srf&searchp=newsearch.srf& dn=616

or

http://tinyurl.com/5tdz3

Is this is where you're hitting 70 mph with the help of a 15
mph tailwind and a 10% grade that is not considered steep
for paved roads in this part of Wales?

The contour lines are 10 meters and the map is 3000 meters
wide. While the map is badly cluttered, the rise from the
roundabout to the east to "PH" in the center appears to be
on the order of 60 meters in 1200, rather closer to a
5%.grade.

That'll be the bit I refer to as tapering out. The steeper section is the
1km to the west of Gwernymynydd crossroads and reading from an 1:50 000
sheet the 10m contour lines are less than 2mm apart making the grade steeper
than 1 in 10 The crossroads also contain traffic lights (mostly) ;-} I'll
try for a larger scale, I could then measure steepest grade with greatest
accuracy. What are you disputing?

Trevor

wrote in message
...
On Fri, 3 Sep 2004 19:52:23 +0100, "Trevor"
wrote:


wrote in message ...

Now I'm truly baffled. I was assuming that you meant the
tiny side road off the A494 running up from Bwlch-y-parc
toward Moel Ethinen.

Originally, you estimated a significant stretch of 10%
grade.

Are you saying that the A494 has a 10% grade somewhere
around Moel Ethinen and that you were pedalling 70 mph down
it?

I'm hard pressed to find a drop of a hundred meters on the
unfortunately crowded topo map in several kilometers on the
A494 around Moel Ethinen--and that stretch ends in a
180-degree hairpin into Llanbedr-Dyffryn-Clwd.


Other way 9kms. turn around, read my post, Gwernymynydd believed to be
1:10 not steep for these parts.

Trevor

Dear Trevor,

Here's Gwernymynydd with the A494 running through it:

http://www.streetmap.co.uk/newmap.sr...v=321500,36250
0&st=4&ar=N&mapp=newmap.srf&searchp=newsearch.srf& dn=616

or

http://tinyurl.com/5tdz3

Is this is where you're hitting 70 mph with the help of a 15
mph tailwind and a 10% grade that is not considered steep
for paved roads in this part of Wales?

The contour lines are 10 meters and the map is 3000 meters
wide. While the map is badly cluttered, the rise from the
roundabout to the east to "PH" in the center appears to be
on the order of 60 meters in 1200, rather closer to a
5%.grade.

That'll be the bit I refer to as tapering out. The steeper section is the
1km to the west of Gwernymynydd crossroads and reading from an 1:50 000
sheet the 10m contour lines are less than 2mm apart making the grade steeper
than 1 in 10 The crossroads also contain traffic lights (mostly) ;-} I'll
try for a larger scale, I could then measure steepest grade with greatest
accuracy. What are you disputing?

Trevor

wrote in message ...
Wind drag increases markedly for an object moving up and
down or side to side relative to the airstream or for an
object changing back and forth between two shapes.

If you think a moment about a situation in which drag is
more noticeable, such as an object moving underwater, this
should be obvious.

Uphill or on the flat, bicyclists have no choice but to
pedal. The steeper the downhill, the quicker they discover
that rapid leg movement is slower than a motionless tuck.


How have you determined this?
How have you determined this?
How have you determined this?

It is simple to show that two riders side by side at 60mph, that the one who
pedals (presumably correctly trained) will accelerate past his companion.
This is self evident that useful force is being applied via the pedals.

Trevor

wrote in message ...
Wind drag increases markedly for an object moving up and
down or side to side relative to the airstream or for an
object changing back and forth between two shapes.

If you think a moment about a situation in which drag is
more noticeable, such as an object moving underwater, this
should be obvious.

Uphill or on the flat, bicyclists have no choice but to
pedal. The steeper the downhill, the quicker they discover
that rapid leg movement is slower than a motionless tuck.


How have you determined this?
How have you determined this?
How have you determined this?

It is simple to show that two riders side by side at 60mph, that the one who
pedals (presumably correctly trained) will accelerate past his companion.
This is self evident that useful force is being applied via the pedals.

Trevor

wrote in message ...
Wind drag increases markedly for an object moving up and
down or side to side relative to the airstream or for an
object changing back and forth between two shapes.

If you think a moment about a situation in which drag is
more noticeable, such as an object moving underwater, this
should be obvious.

Uphill or on the flat, bicyclists have no choice but to
pedal. The steeper the downhill, the quicker they discover
that rapid leg movement is slower than a motionless tuck.


How have you determined this?
How have you determined this?
How have you determined this?

It is simple to show that two riders side by side at 60mph, that the one who
pedals (presumably correctly trained) will accelerate past his companion.
This is self evident that useful force is being applied via the pedals.

Trevor

wrote in message ...
On Fri, 3 Sep 2004 20:09:52 +0100, "Trevor"
wrote:


wrote in message ...
Why do motorcycle front tires break free just a wee bit in
corners and remain controllable, while bicycle tires do not?
That is, what is the difference? It has something to do with
a "wee bit," but I'd be hard-pressed to try to explain this
theory to an engineer. Give me some help.

As I see it, the width of the tyre allows it to creep sideways at the
limits
of adhesion due to the larger width of the contact patch. Part of the
patch
can be sliding whilst part is still adhering.

Trevor

Dear Trevor,

Sorry, but I can't see how this would occur.

Given that the limit of traction had already been reached in
order for some of the rubber to break free, what extra force
steps in to holding the remaining rubber firmly against the
ground?

Which part of the patch has breaks free to slide in the
corer while the rest of the tire adheres to the road? The
leading edge, the outside edge, the trailing edge, the
inside edge, or the center?

If some part of the tire still adhere to the road, but
another part breaks away, do the two parts rip asunder? Or
does the rubber in between them stretch?

Why would the width of a motorcycle tire's contact patch
allow this phenomenon to occur, while the width of a bicycle
tire's patch does not? Both can be measured with an ordinary
ruler.

Still baffled,

The evidence is in the black tyre marks left on the roadway. If the amount
of rubber left on bends was indicative of the number of full on skids nobody
would finish the race. I could explain but I suggest that you hunt down a
technical book on motor cycle racing if you really want to know. This is
how I learnt what was happening and cannot recall in detail or the name of
the book.

Trevor