Bicycle Drift, revisited...

Paul M. Hobson said:

A while back, there was a thread discussing the technique, equipment,
and road conditions required to "peel out" on a bicycle like this:

I won't pretend to know exactly where this footage was shot.  But I
wonder if the video below could possibly shed some insight into the road
surface that allows such a feat to be possible:

Any thoughts?
\\paul

Yeah, I've got a thought.
Arab roads are paved with glass.
Or petroleum jelly.

ABS

Paul M. Hobson said:

A while back, there was a thread discussing the technique,
equipment, and road conditions required to "peel out" on a bicycle
like this:

Quoted message said:

I won't pretend to know exactly where this footage was shot. But I
wonder if the video below could possibly shed some insight into the
road surface that allows such a feat to be possible:

You'll notice the bicyclists are riding in winter with gloves and warm
clothes and if you look even closer, I am sure they are riding on a
street with ice on it. Their skid paths leave white ice granules on
the otherwise uniformly slick surface.

Besides, their traction is so poor that they don't lean in turns and
don't have much propulsion traction either.

Jobst Brandt

In article <[email hidden]>, Paul M. Hobson

Quoted message said:

A while back, there was a thread discussing the technique, equipment,
and road conditions required to "peel out" on a bicycle like this:

I won't pretend to know exactly where this footage was shot. But I
wonder if the video below could possibly shed some insight into the road
surface that allows such a feat to be possible:

Any thoughts?
\\paul

I suspect the condition of the road has less to do with the particulars
than the condition of the tire (in video one) and the sandals (in video
2).

In the first video it seems a white residue is present in the wake of
the hotdogger's burn outs. Perhaps the cyclist dipped applied a can of
Pam or lard to his rear tire. ;-)

Quoted message said:

Paul M. Hobson said:

A while back, there was a thread discussing the technique,
equipment, and road conditions required to "peel out" on a bicycle
like this:

Quoted message said:

I won't pretend to know exactly where this footage was shot. But I
wonder if the video below could possibly shed some insight into the
road surface that allows such a feat to be possible:

You'll notice the bicyclists are riding in winter with gloves and warm
clothes and if you look even closer, I am sure they are riding on a
street with ice on it. Their skid paths leave white ice granules on
the otherwise uniformly slick surface.

Besides, their traction is so poor that they don't lean in turns and
don't have much propulsion traction either.

Jobst Brandt

Dear Jobst,

Yes, you just as sure that it was ice the last time that this video
was discussed:

http://groups.google.com/group/rec.bicycles.tech/browse_frm/thread/1d2c2d866244f2fe/682fdf61c4070286?lnk=gst&q=drifting+bleach#682fdf61c4070286

But everyone seemed to disagree with your theory.

Most people ended up thinking about bleach on the rear tire or the
extremely fine sand that's found in some areas.

The gloves aren't exactly an indicator of frost. After all, lots of
people wear gloves when they do bicycle stunts, regardless of the
temperature.

As for the poor traction, the rider's front wheel never seems to slip
as if it was on any icy surface.

Bleach or fine sand might explain both the bicycle video _and_ the car
video, but it's not likely that there was any ice on that Arabian
highway.

Cheers,

Carl Fogel

<[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Quoted message said:

Paul M. Hobson said:

A while back, there was a thread discussing the technique,
equipment, and road conditions required to "peel out" on a bicycle
like this:

Quoted message said:

I won't pretend to know exactly where this footage was shot. But I
wonder if the video below could possibly shed some insight into the
road surface that allows such a feat to be possible:

You'll notice the bicyclists are riding in winter with gloves and warm
clothes and if you look even closer, I am sure they are riding on a
street with ice on it. Their skid paths leave white ice granules on
the otherwise uniformly slick surface.

Besides, their traction is so poor that they don't lean in turns and
don't have much propulsion traction either.

Jobst Brandt

Dear Jobst,

Yes, you just as sure that it was ice the last time that this video
was discussed:

http://groups.google.com/group/rec.bicycles.tech/browse_frm/thread/1d2c2d866244f2fe/682fdf61c4070286?lnk=gst&q=drifting+bleach#682fdf61c4070286

But everyone seemed to disagree with your theory.

Most people ended up thinking about bleach on the rear tire or the
extremely fine sand that's found in some areas.

The gloves aren't exactly an indicator of frost. After all, lots of
people wear gloves when they do bicycle stunts, regardless of the
temperature.

As for the poor traction, the rider's front wheel never seems to slip
as if it was on any icy surface.

Bleach or fine sand might explain both the bicycle video _and_ the car
video, but it's not likely that there was any ice on that Arabian
highway.

You'll also notice that the rider is leaning very far forward reducing
the weight on the rear wheel. When he sits on the seat traction returns.

Phil H

Paul M. Hobson said:

A while back, there was a thread discussing the technique, equipment,
and road conditions required to "peel out" on a bicycle like this:

I won't pretend to know exactly where this footage was shot.  But I
wonder if the video below could possibly shed some insight into the road
surface that allows such a feat to be possible:

Any thoughts?
\\paul

Yeah, two of them:

1. It's lucky for those guys that lanes on a Riyadh highway are
delineated with paint, not Botts' dots.

2. It's almost surely fine sand in the second video. Ice in Riyadh?
There's a reason they built a place called "Snow World" there. At
about 24 degrees North latitude and 2000 feet elevation, they don't
exactly get a lot of snow and ice. Even if it did happen, those cars
on the highway would not be driving at that speed. Further, if it was
cold enough to sustain a thin layer of ice on a black roadway in the
sun, those men would not be enjoying themselves with exposed skin in
the wind at highway speeds. You can be certain it is not ice. If it
were some sort of slippery substance on the men's shoes, the substance
would be consumed. The distance they travel during the video indicates
that the roadway is almost surely the source of the friction-reducing
material. And since it isn't ice, what else can it be other than fine
sand? And in light of that, it's likely that the phenomenon in the
second video is the same as the one in the first.

Stephen Greenwood

On Sun, 6 Jan 2008 19:41:02 -0800, "Phil Holman"

piholmanc@yourservice said:

<[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Quoted message said:

Paul M. Hobson writes:

> A while back, there was a thread discussing the technique,
> equipment, and road conditions required to "peel out" on a bicycle
> like this:

> I won't pretend to know exactly where this footage was shot. But I
> wonder if the video below could possibly shed some insight into the
> road surface that allows such a feat to be possible:

You'll notice the bicyclists are riding in winter with gloves and warm
clothes and if you look even closer, I am sure they are riding on a
street with ice on it. Their skid paths leave white ice granules on
the otherwise uniformly slick surface.

Besides, their traction is so poor that they don't lean in turns and
don't have much propulsion traction either.

Jobst Brandt

Dear Jobst,

Yes, you just as sure that it was ice the last time that this video
was discussed:

http://groups.google.com/group/rec.bicycles.tech/browse_frm/thread/1d2c2d866244f2fe/682fdf61c4070286?lnk=gst&q=drifting+bleach#682fdf61c4070286

But everyone seemed to disagree with your theory.

Most people ended up thinking about bleach on the rear tire or the
extremely fine sand that's found in some areas.

The gloves aren't exactly an indicator of frost. After all, lots of
people wear gloves when they do bicycle stunts, regardless of the
temperature.

As for the poor traction, the rider's front wheel never seems to slip
as if it was on any icy surface.

Bleach or fine sand might explain both the bicycle video _and_ the car
video, but it's not likely that there was any ice on that Arabian
highway.

You'll also notice that the rider is leaning very far forward reducing
the weight on the rear wheel. When he sits on the seat traction returns.

Phil H

Dear Phil,

True.

However, the sandal-skidders appear to have full weight on their feet
for about a mile of apparently dry asphalt on a busy highway at much
higher speeds.

If it's something on their shoes (like bleach), I'm astonished that it
lasts so long, but a really slippery sole would explain why their feet
aren't smoking.

I like to think that, somewhere out there, happy young Arabs are
having a wonderful time, sliding wildly on bicycles and sandals and
laughing about how clueless and easily astonished certain posters on
RBT are.

Cheers,

Carl Fogel

Stephen Greenwood said:

Paul M. Hobson said:

A while back, there was a thread discussing the technique, equipment,
and road conditions required to "peel out" on a bicycle like this:

I won't pretend to know exactly where this footage was shot.  But I
wonder if the video below could possibly shed some insight into the road
surface that allows such a feat to be possible:

Any thoughts?
\\paul

Yeah, two of them:

1. It's lucky for those guys that lanes on a Riyadh highway are
delineated with paint, not Botts' dots.

2. It's almost surely fine sand in the second video. Ice in Riyadh?
There's a reason they built a place called "Snow World" there. At
about 24 degrees North latitude and 2000 feet elevation, they don't
exactly get a lot of snow and ice. Even if it did happen, those cars
on the highway would not be driving at that speed. Further, if it was
cold enough to sustain a thin layer of ice on a black roadway in the
sun, those men would not be enjoying themselves with exposed skin in
the wind at highway speeds. You can be certain it is not ice. If it
were some sort of slippery substance on the men's shoes, the substance
would be consumed. The distance they travel during the video indicates
that the roadway is almost surely the source of the friction-reducing
material. And since it isn't ice, what else can it be other than fine
sand? And in light of that, it's likely that the phenomenon in the
second video is the same as the one in the first.

Stephen Greenwood

Dear Stephen,

Fine sand and bleach were the most popular theories with the original
bicycle video.

***

The trouble with bleach is that it seems to last an awfully long time
down that highway, though I suppose that if you soaked the sandals
overnight bleach (or something similar), it might last longer than
expected.

***

The trouble with fine sand is that the sandals show no sign of
smoking, much less being sandpapered off under full body weight for
over a mile at high speed.

Nor does there seem to be any sand blown up by the draft of the
numerous cars. If it's really fine sand, you'd expect to see a least a
little sand storm. The white robes aren't getting dirty, as far as I
can see.

The cars on the busy road show no sign of poor traction, but the
sandals are probably much more lightly loaded per square inch than car
tires.

And maybe ultra-fine free sand doesn't work like sand glued to a belt
sander.

***

I'd love to have the trick explained by someone who actually does it.

I'd like it even more if it turns out to be something none of us have
thought of.

Cheers,

Carl Fogel

Quoted message said:

The trouble with bleach is that it seems to last an awfully long time
down that highway, though I suppose that if you soaked the sandals
overnight bleach (or something similar), it might last longer than
expected.

Hi Carl,

Maybe. It would have to be a *lot* longer than I expect. I've heard of
people pouring bleach on the ground to help initiate a burnout with
cars and motorcycles, but never heard of anyone pouring it on the tire
itself.

Quoted message said:

The trouble with fine sand is that the sandals show no sign of
smoking, much less being sandpapered off under full body weight for
over a mile at high speed.

Nor does there seem to be any sand blown up by the draft of the
numerous cars. If it's really fine sand, you'd expect to see a least a
little sand storm. The white robes aren't getting dirty, as far as I
can see.

I thought of that, but assumed it was simply beyond the camera's
resolution in the second video. There is a little "trail" visible in
the first one.

Quoted message said:

The cars on the busy road show no sign of poor traction, but the
sandals are probably much more lightly loaded per square inch than car
tires.

My thought also.

Quoted message said:

And maybe ultra-fine free sand doesn't work like sand glued to a belt
sander.

Yes, I imagine the fine sand acts more like tiny spheres rolling,
rather than translating and abrading the sandals or tires.

Quoted message said:

I'd love to have the trick explained by someone who actually does it.

Indeed that would be cool. I still vote for the sand, though. Check
this one out:

The spray (for lack of a better word) and the "trail" are clearly
visible. How can any tire, even a bleach-impregnated one, fling up so
much material? A glance at the guy's clothing suggests it isn't ice in
that one, either.

Bettery yet, try this one:

Look at the part at about 0:35. Even with the poor video quality, a
significant amount of spray is visible when the fellow crashes. His
falling body produces a little cloud of dust. That can't come from
bleached tires, but sure is consistent with fine sand. And I can't
help but notice that all four of these videos appear to be from Arab
or Middle Eastern countries.

Stephen Greenwood

Stephen Greenwood said:

Quoted message said:

The trouble with bleach is that it seems to last an awfully long time
down that highway, though I suppose that if you soaked the sandals
overnight bleach (or something similar), it might last longer than
expected.

Hi Carl,

Maybe. It would have to be a *lot* longer than I expect. I've heard of
people pouring bleach on the ground to help initiate a burnout with
cars and motorcycles, but never heard of anyone pouring it on the tire
itself.

Quoted message said:

The trouble with fine sand is that the sandals show no sign of
smoking, much less being sandpapered off under full body weight for
over a mile at high speed.

Nor does there seem to be any sand blown up by the draft of the
numerous cars. If it's really fine sand, you'd expect to see a least a
little sand storm. The white robes aren't getting dirty, as far as I
can see.

I thought of that, but assumed it was simply beyond the camera's
resolution in the second video. There is a little "trail" visible in
the first one.

Quoted message said:

The cars on the busy road show no sign of poor traction, but the
sandals are probably much more lightly loaded per square inch than car
tires.

My thought also.

Quoted message said:

And maybe ultra-fine free sand doesn't work like sand glued to a belt
sander.

Yes, I imagine the fine sand acts more like tiny spheres rolling,
rather than translating and abrading the sandals or tires.

Quoted message said:

I'd love to have the trick explained by someone who actually does it.

Indeed that would be cool. I still vote for the sand, though. Check
this one out:

The spray (for lack of a better word) and the "trail" are clearly
visible. How can any tire, even a bleach-impregnated one, fling up so
much material? A glance at the guy's clothing suggests it isn't ice in
that one, either.

Bettery yet, try this one:

Look at the part at about 0:35. Even with the poor video quality, a
significant amount of spray is visible when the fellow crashes. His
falling body produces a little cloud of dust. That can't come from
bleached tires, but sure is consistent with fine sand. And I can't
help but notice that all four of these videos appear to be from Arab
or Middle Eastern countries.

Stephen Greenwood

Dear Stephen,

The more I look at those videos and the related drifting videos that
show up next to them, the more I'm inclined to agree with you that
it's very fine sand.

In many of them, something is being thrown up from the pavement.
probably the fine sand.

In others, the spinning tires leave little tracks behind them that I
suspect are actually sand piles, places where the sand scuffed off the
pavement has piled up. It's so fine that it isn't thrown more than an
inch or two from the bike tire.

Two related things belatedly occur to me.

Long ago, half the Rocky Mountain Trials Association spent an hour
making fools of ourselves on a peculiar rounded bare hillside at Left
Hand Canyon. The surface was very hard, very gritty, and ridiculously
easy to get stuck on. Even on a gentle slope, you could get stuck and
spin the tire on what we called dry ice just by shifting your weight
wrong.

More recently, there's a dull, gentle trail above Wetmore that I hate.

I hate it partly because it's so dull. There's nothing interesting.
much less challenging, on the trail, no ledges, rock fields, mud bogs,
hairpins, climbs, or root walls.

But the real reason that I hate it is thatthere's an innocent looking
stretch of slightly rising trail near the top that's covered with
dust, sand, and grit on loose, flat rocks. It might as well be ice,
because the rear tire spins without provocation, and you can get stuck
when your front tire hits a three-inch rock on what you'd swear is
practically flat ground.

So my vote is drifting toward your sand theory.

I'd love to see some geological site that compares sand grain size in
Arabia and North Africa to whatever we grow around here.

Cheers,

Carl Fogel

Quoted message said:

On Sun, 6 Jan 2008 22:20:19 -0800 (PST), Stephen Greenwood

Quoted message said:

Quoted message said:

The trouble with bleach is that it seems to last an awfully long time
down that highway, though I suppose that if you soaked the sandals
overnight bleach (or something similar), it might last longer than
expected.

Quoted message said:

Hi Carl,

Quoted message said:

Maybe. It would have to be a *lot* longer than I expect. I've heard of
people pouring bleach on the ground to help initiate a burnout with
cars and motorcycles, but never heard of anyone pouring it on the tire
itself.

Quoted message said:

Quoted message said:

The trouble with fine sand is that the sandals show no sign of
smoking, much less being sandpapered off under full body weight for
over a mile at high speed.

Quoted message said:

Quoted message said:

Nor does there seem to be any sand blown up by the draft of the
numerous cars. If it's really fine sand, you'd expect to see a least a
little sand storm. The white robes aren't getting dirty, as far as I
can see.

Quoted message said:

I thought of that, but assumed it was simply beyond the camera's
resolution in the second video. There is a little "trail" visible in
the first one.

Quoted message said:

Quoted message said:

The cars on the busy road show no sign of poor traction, but the
sandals are probably much more lightly loaded per square inch than car
tires.

Quoted message said:

My thought also.

Quoted message said:

Quoted message said:

And maybe ultra-fine free sand doesn't work like sand glued to a belt
sander.

Quoted message said:

Yes, I imagine the fine sand acts more like tiny spheres rolling,
rather than translating and abrading the sandals or tires.

Quoted message said:

Quoted message said:

I'd love to have the trick explained by someone who actually does it.

Quoted message said:

Indeed that would be cool. I still vote for the sand, though. Check
this one out:

Quoted message said:

Quoted message said:

The spray (for lack of a better word) and the "trail" are clearly
visible. How can any tire, even a bleach-impregnated one, fling up so
much material? A glance at the guy's clothing suggests it isn't ice in
that one, either.

Quoted message said:

Bettery yet, try this one:

Quoted message said:

Quoted message said:

Look at the part at about 0:35. Even with the poor video quality, a
significant amount of spray is visible when the fellow crashes. His
falling body produces a little cloud of dust. That can't come from
bleached tires, but sure is consistent with fine sand. And I can't
help but notice that all four of these videos appear to be from Arab
or Middle Eastern countries.

Quoted message said:

Stephen Greenwood

Dear Stephen,

The more I look at those videos and the related drifting videos that
show up next to them, the more I'm inclined to agree with you that
it's very fine sand.

In many of them, something is being thrown up from the pavement.
probably the fine sand.

In others, the spinning tires leave little tracks behind them that I
suspect are actually sand piles, places where the sand scuffed off the
pavement has piled up. It's so fine that it isn't thrown more than an
inch or two from the bike tire.

Two related things belatedly occur to me.

Long ago, half the Rocky Mountain Trials Association spent an hour
making fools of ourselves on a peculiar rounded bare hillside at Left
Hand Canyon. The surface was very hard, very gritty, and ridiculously
easy to get stuck on. Even on a gentle slope, you could get stuck and
spin the tire on what we called dry ice just by shifting your weight
wrong.

More recently, there's a dull, gentle trail above Wetmore that I hate.

I hate it partly because it's so dull. There's nothing interesting.
much less challenging, on the trail, no ledges, rock fields, mud bogs,
hairpins, climbs, or root walls.

But the real reason that I hate it is thatthere's an innocent looking
stretch of slightly rising trail near the top that's covered with
dust, sand, and grit on loose, flat rocks. It might as well be ice,
because the rear tire spins without provocation, and you can get stuck
when your front tire hits a three-inch rock on what you'd swear is
practically flat ground.

So my vote is drifting toward your sand theory.

I'd love to see some geological site that compares sand grain size in
Arabia and North Africa to whatever we grow around here.

Sand plus a very slick, shiny pavement. Guessing, this seems to be
some sort of macadam that is not all melty (tar not flying all over
the place) in the presumed high daylight temps there.

There's some traction, as the autos and bike front wheels aren't just
sliding all over the place as they (probably) would on slick ice.

I also noticed the skating sandal dudes don't leave their feet down
for very long at a time, and the changing-feet intervals seem fairly
regular. "How long does it take to heat up a sandal at 45mph?" --D-y

Quoted message said:

I'd love to see some geological site that compares sand grain size in
Arabia and North Africa to whatever we grow around here.

We have a friend who just visited from Baghdad. He works in the
International Zone.

He describes the sand as being like talcum powder. He says that as
you walk, each footfall raises a little cloud of dust particles. And
that it gets everywhere.

He's a little worried about the effect on his lungs, and is literally
counting the days until he's off that assignment.

He was once a racing cyclist, but I doubt he's even considered riding
there.

- Frank Krygowski

All you guys are way over-thinking this.
It's obviously a miracle from Allah.

ABS

Quoted message said:

All you guys are way over-thinking this.

Over-thinking what?

Quoted message said:

It's obviously a miracle from Allah.
ABS

Anti-Brake Socks?

Paul M. Hobson said:

A while back, there was a thread discussing the technique, equipment,
and road conditions required to "peel out" on a bicycle like this:

I won't pretend to know exactly where this footage was shot. But I
wonder if the video below could possibly shed some insight into the road
surface that allows such a feat to be possible:

Some roads in Malta are like that after heavy rain. The buses and cars
slow down to walking pace.

amongst other things

[email hidden] wrote in
news:[email hidden]:

Quoted message said:

***

The trouble with bleach is that it seems to last an awfully long time
down that highway, though I suppose that if you soaked the sandals
overnight bleach (or something similar), it might last longer than
expected.

***

The trouble with fine sand is that the sandals show no sign of
smoking, much less being sandpapered off under full body weight for
over a mile at high speed.

Nor does there seem to be any sand blown up by the draft of the
numerous cars. If it's really fine sand, you'd expect to see a least a
little sand storm. The white robes aren't getting dirty, as far as I
can see.

The cars on the busy road show no sign of poor traction, but the
sandals are probably much more lightly loaded per square inch than car
tires.

Is bleach slippery? I don't have any on hand for a test, but I suspect it
would not be particularly so.

And if those guys sliding along with the car were on anything other than
ice they would be getting mighty hot feet.

Bruce

BJ said:

Is bleach slippery? I don't have any on hand for a test, but I suspect it
would not be particularly so.

And if those guys sliding along with the car were on anything other than
ice they would be getting mighty hot feet.

Bruce

Dear Bruce,

I think that you're right about bleach and that I was wrong.

In the long-ago thread, I mentioned finding suggestions about bleach,
but it turns out to be (I think) more for softening the rubber of drag
strip tires and producing dramatic smoke, not for skidding.

Marcus Coles said so, but I simply forgot the details:
http://groups.google.com/group/rec.bicycles.tech/msg/597f5381d838c666

Sorry, Marcus.

As for the car-skaters, others have pointed out that they switch feet
more often than I thought, so yes, their feet might have been getting
hot through the sandals.

Ice on a busy Saudi highway is an increasingly improbable explanation.

Amazingly fine sand seems to be quite plausible. I can't find anything
like the car-skaters, bike drifters, or spinning cars on U.S. roads,
so I suspect that our sand grains are just too big or too scarce.
Otherwise, teenagers in Texas and Arizona would be imitating the Arab
riders, drivers, and skaters.

You can see Arab drivers spinning cars like tops for crowds on desert
roads in the related videos to the right of the one that Paul posted:

They just keep swapping ends down the roads, right past the crowds, as
if they're on ice, instead of catching traction and swerving off
violently to one side or the other.

Incidentally, thanks, Paul, for starting the thread with that
eye-catching video.

Cheers,

Carl Fogel

Quoted message said:

You can see Arab drivers spinning cars like tops for crowds on desert
roads in the related videos to the right of the one that Paul posted:

They just keep swapping ends down the roads, right past the crowds, as
if they're on ice, instead of catching traction and swerving off
violently to one side or the other.

Incidentally, thanks, Paul, for starting the thread with that
eye-catching video.

Cheers,

Carl Fogel

After marveling at the videos of amazing skid-control on what seem to
be sandy roads, I began wondering whether it was quite as safe as the
videos made it look.

It's not.

Some horrifying examples of what the newspapers mean when they mention
that the driver and passengers were not wearing seat belts and were
ejected from the car:

Cheers,

Carl Fogel

On 2008-01-08, [email hidden] <[email hidden]> wrote:
[...]

Quoted message said:

Amazingly fine sand seems to be quite plausible. I can't find anything
like the car-skaters, bike drifters, or spinning cars on U.S. roads,
so I suspect that our sand grains are just too big or too scarce.
Otherwise, teenagers in Texas and Arizona would be imitating the Arab
riders, drivers, and skaters.

You can see Arab drivers spinning cars like tops for crowds on desert
roads in the related videos to the right of the one that Paul posted:

They just keep swapping ends down the roads, right past the crowds, as
if they're on ice, instead of catching traction and swerving off
violently to one side or the other.

Still they are going quite fast. It looks like they have more grip than
you would on ice, although less than on a good dry road in the summer.

I wonder if the sandal skaters aren't also putting quite a lot of their
weight on the car door rather than on the road. That would help quite a
bit.