Do cyclists make better motorcyclists?

On Tue, 31 Aug 2004 18:38:31 GMT, "Callistus Valerius"
wrote:

Are you riding your kids BMX bike on the little hill behind your
house?
When I'm descending 8% grades, I sometimes pass motorcyclists at 55 mph.
Bicycling, like what we are talking in this newsgroup (not kids BMX
bikes)
takes much more talent. For one, your center of gravity is so much
higher
than on a motorcycle.

Dear Cal,

When I plug in 0 watts for coasting and -0.08 for an 8%
grade, it appears that you and your bicycle need to weigh
around 273 pounds to reach 55 mph (24.6 meters per second):

http://www.analyticcycling.com/ForcesSpeed_Page.html

Even if you and your bike really are reaching 55 mph on 8%
grades, I suspect that the motorcycles could out-corner you
if they were interested. And if you're braking, you're no
longer doing 55 mph.

I'm talking about a screamer, slight curves. Did you figure wind in
your calculation? Of course, a motorcycle is easier, they can use their
transmission, and disc brakes to keep everything under control. A road bike
has a pair of crummy rim brakes, and by sitting up as a wind brake to
control things. I've done both, and it's a mix. The one thing I would
totally agree with you, is that the engine of a motorcycle can get you into
a lot more trouble than a bicycle engine can, if you ride outside your
ability.


Dear Cal,

I don't know what kind of wind you might have in mind when
you believe that you're passing motorcycles downhill on an
8% grade at 55 mph.

You can get a depressingly good idea of how fast objects
shaped like normal touring bicycles carrying objects shaped
like normal riders roll downhill by plugging 0 into the
watts and the total weight in kg into this calculator and
leaving the defaults alone:

http://www.analyticcycling.com/ForcesSpeed_Page.html

You can convert just about any speed short of furlongs per
fortnight instantly for all values at this page:

http://members.aol.com/javawizard/speed.html

Or just convert meters per second to miles per hour by
multiplying mps x 2.25 = mph (actually 2.236, but two and a
quarter is easy to remember).

A 200 pound (91kg) bicycle and rider coasting down an 8%
grade with the other defaults set reaches about 47 mph.
Adding 8 mph to reach 55 mph takes another 73 pounds (124kg
total). At such speeds, enormous force is needed to overcome
the wild increase of wind drag with each additional mile per
hour.

You could raise the speed estimate a bit if you know the
altitude--there's a field for adjusting that value.

A tailwind, of course, helps. My daily ride involves
dropping down a curve over the bluffs down to the Arkansas
River. Day in, day out, the speedometer records a maximum
speed of 39 mph for a rider coasting down and imitating an
egg. But every few years, I break 50 mph because the wind is
blowing just right. I once hit 54 mph long enough for it to
register. On a bicycle, tucked in, this seems fast, but
easily controllable. On a motorcycle, it's a ho-hum
one-handed stretch of smoothly curving road posted at 65
mph.

A surprising number of speed estimates for bicycling turn
out to involve grades that magicallly steepen, winds that
weren't mentioned to start with, and aerodynamic secrets
unknown to anyone else. They also turn out to be hard to
reproduce.

Of course, the analytic cycling calculator may not be
infallibly accurate, and there are all sorts of interesting
parameters that can be changed to improve theoretical
speeds. But it's a useful tool for understanding why I can
roll downhill faster at around 220 pounds of bike and rider
than Lance Armstrong, while Chalo Colina (around 400 pounds
total) enjoys thrills unknown to the rest of us.

On a long 8% grade, Chalo is likely to hit around 66 mph,
I'm hoping for 49 mph, and a 163 pound racer with a 17 pound
bike is probably rolling at just under 45 mph. Frontal area
and drag coefficient can alter these speeds, but even
someone as big as Chalo can tuck in surprisingly well.

The weight factor, incidentally, is why loaded trucks worry
so much about downhills that tourists in sedans hardly
notice. The trucks have to ride their brakes all the way
down the pass, or else they coast up, like Chalo, to
impressively faster speeds.

In any case, you're saying now that this section of road is
"a screamer, slight curves." It may be a "screamer" on a
bicycle if you're not used to an 8% grade, but "slight
curves" doesn't sound like any impressive cornering is
involved.

I try to keep an open mind, but in general it seems to me
that most bicyclists rarely approach the limits of traction
when cornering and that most of them over-estimate their
speeds. The same thing seems to be true of motorcyclists.

Carl Fogel

On Tue, 31 Aug 2004 13:49:16 -0700, "Tom Nakashima"
wrote:


wrote in message
.. .

That we're going back 18 years to find impressive cornering
suggests how rarely it matters even in the most important
races.

And it's likely that the other riders could have kept close,
if not up--they just didn't see any point. In fact, given
motivation, it's likely that some of the other hundred or so
racers could have cornered faster--Hinault and Lemond would
have been in front and competing because their overall times
made the competition worth while, but they got to the front
by pedalling faster in the earlier stages, not by brilliant
cornering skills.

Carl Fogel

Actually going back 18 years was just an example of how cyclist can take the
corners, lean angle.
Today of course most all the Tour de France riders can corner like that, I'm
sure you know.

Getting back to the subject, "do cyclist make better motorcyclists?" I'll
have to say no, two different machines.

I was a cyclist before I was a motorcyclist. One of the worst things I
tried to do was ride the motorcycle like a bicycle. Hello, there's a
throttle there! After many years of motorcycling and non cycling, I got
back into bicycles, and did a complete opposite, I tired to ride the bicycle
like a motorcycle, no possible way.
As far as picking your lines in the corners, it's the same, but not the same
leaning into the curve and or accelerating out of the curve.

I'm wondering if you ever rode motorcycles Carl? You just can't compare the
two if you haven't.
http://www.research-racing.de/mex154.jpg
-tom


Dear Tom,

Apart from reaching master class status in the Rocky
Mountain Trials Association in 1974, setting up events,
teaching in trials schools, and--let's see--thirty-six years
of off-road riding in the Rocky Mountains since I was twelve
years old, I can scarcely claim to know one end of a
motorcycle from the other.

But somewhere or other I've heard that the fastest lines
through corners are actually quite different for bicycle and
motorcycles.

The racing bicyclist's aim is to maintain as high a speed as
possible throughout the entire turn because a bicycle
accelerates like a snail. What matters is not letting your
speed drop any lower than absolutely necessary, so you take
the widest, smoothest, most symmetrical line consistent
with the apex of the corner, something like this ) curve.

The racing motorcyclist, on the other hand, benefits from
braking far harder into the beginning of a turn and making a
much sharper, shorter, and uglier turn in order to get
squared away as soon as possible and use the engine to
drag-race to the next corner. The fastest motorcycle line
through a corner is more like an L than the ( of a bicycle..

Bicyclists strive to glide smoothly through turns without
losing speed, while motorcyclists stuff the front wheel into
turns, throw out the anchor, get lined up for the next turn,
and pull the trigger.

In addition to braking harder, the motorcyclist has to worry
about not accelerating too hard or too soon because his
engine can break his rear tire loose when he opens the
throttle, a danger unknown to bicyclists.

Of course, either technique can be used by either vehicle.
It's just that the wrong technique is slower.

As for the importance of cornering in motorcycling, I once
had my nose rubbed in it quite unintentionally. Near the end
of the 2-day Ute Cup Trial, I stopped to open a stubborn
barb-wire gate on a fast mountain trail. While I was rolling
my machine through, a wiry fellow twice my age arrived,
rolled through, parked his machine, and said here, let me
help you shut that. My contribution consisted of slipping
the wire loop over the wooden stick while he effortlessly
pulled the rusty, tangled mess close to the post.

After we kicked our machines back to life, he set out with
about a ten-yard head start. Our machines were effectively
identical Bultaco Sherpa T 326cc trials bikes. Back then, I
was a young and fairly fast rider for Colorado.

He disappeared from sight in the pine trees in a minute or
two. My engine was just as powerful as his, but some
mysterious force kept my throttle from opening as wide as
his opened, possibly my firm belief that it was insane to go
that fast.

He was retired, you see, and riding in the exhibition class,
but he knew a lot more than most people about cornering on
that kind of motorcycle. After all, he developed it. He also
won 7 Scott Trophies, several Scottish Six Day Trials, three
World Trials championships, numerous International Six Day
Trials, several Welsh Three Day Trials, and was champion of
Britain eleven years in a row in an era when that meant more
than the world trials championship. All that was after he
gave up a decent road racing career.

What really hurt my feelings was that Sammy Miller was on
vacation and just enjoying the Colorado scenery, not trying
to show off by going fast. He just didn't know how to corner
as slowly as riders like me. When not rocketing between
sections on the two 20-mile daily loops, he spent so much
time chatting with observers that he ended up with 0.3
penalty points for being 3 minutes late the second day.

He also didn't know how to put his feet down. S. Miller won
that Ute Cup handily, losing only 16 marks on observation in
the obstacle sections, half as many as L. Leavitt, the best
U.S. rider at the time, with a score of 32.

C. Fogel disgraced the Don's Cycles team by losing 163
marks, but learned that he was actually nowhere near the
limits of his machine's cornering abilities.

Carl Fogel

On Tue, 31 Aug 2004 13:49:16 -0700, "Tom Nakashima"
wrote:


wrote in message
.. .

That we're going back 18 years to find impressive cornering
suggests how rarely it matters even in the most important
races.

And it's likely that the other riders could have kept close,
if not up--they just didn't see any point. In fact, given
motivation, it's likely that some of the other hundred or so
racers could have cornered faster--Hinault and Lemond would
have been in front and competing because their overall times
made the competition worth while, but they got to the front
by pedalling faster in the earlier stages, not by brilliant
cornering skills.

Carl Fogel

Actually going back 18 years was just an example of how cyclist can take the
corners, lean angle.
Today of course most all the Tour de France riders can corner like that, I'm
sure you know.

Getting back to the subject, "do cyclist make better motorcyclists?" I'll
have to say no, two different machines.

I was a cyclist before I was a motorcyclist. One of the worst things I
tried to do was ride the motorcycle like a bicycle. Hello, there's a
throttle there! After many years of motorcycling and non cycling, I got
back into bicycles, and did a complete opposite, I tired to ride the bicycle
like a motorcycle, no possible way.
As far as picking your lines in the corners, it's the same, but not the same
leaning into the curve and or accelerating out of the curve.

I'm wondering if you ever rode motorcycles Carl? You just can't compare the
two if you haven't.
http://www.research-racing.de/mex154.jpg
-tom


Dear Tom,

Apart from reaching master class status in the Rocky
Mountain Trials Association in 1974, setting up events,
teaching in trials schools, and--let's see--thirty-six years
of off-road riding in the Rocky Mountains since I was twelve
years old, I can scarcely claim to know one end of a
motorcycle from the other.

But somewhere or other I've heard that the fastest lines
through corners are actually quite different for bicycle and
motorcycles.

The racing bicyclist's aim is to maintain as high a speed as
possible throughout the entire turn because a bicycle
accelerates like a snail. What matters is not letting your
speed drop any lower than absolutely necessary, so you take
the widest, smoothest, most symmetrical line consistent
with the apex of the corner, something like this ) curve.

The racing motorcyclist, on the other hand, benefits from
braking far harder into the beginning of a turn and making a
much sharper, shorter, and uglier turn in order to get
squared away as soon as possible and use the engine to
drag-race to the next corner. The fastest motorcycle line
through a corner is more like an L than the ( of a bicycle..

Bicyclists strive to glide smoothly through turns without
losing speed, while motorcyclists stuff the front wheel into
turns, throw out the anchor, get lined up for the next turn,
and pull the trigger.

In addition to braking harder, the motorcyclist has to worry
about not accelerating too hard or too soon because his
engine can break his rear tire loose when he opens the
throttle, a danger unknown to bicyclists.

Of course, either technique can be used by either vehicle.
It's just that the wrong technique is slower.

As for the importance of cornering in motorcycling, I once
had my nose rubbed in it quite unintentionally. Near the end
of the 2-day Ute Cup Trial, I stopped to open a stubborn
barb-wire gate on a fast mountain trail. While I was rolling
my machine through, a wiry fellow twice my age arrived,
rolled through, parked his machine, and said here, let me
help you shut that. My contribution consisted of slipping
the wire loop over the wooden stick while he effortlessly
pulled the rusty, tangled mess close to the post.

After we kicked our machines back to life, he set out with
about a ten-yard head start. Our machines were effectively
identical Bultaco Sherpa T 326cc trials bikes. Back then, I
was a young and fairly fast rider for Colorado.

He disappeared from sight in the pine trees in a minute or
two. My engine was just as powerful as his, but some
mysterious force kept my throttle from opening as wide as
his opened, possibly my firm belief that it was insane to go
that fast.

He was retired, you see, and riding in the exhibition class,
but he knew a lot more than most people about cornering on
that kind of motorcycle. After all, he developed it. He also
won 7 Scott Trophies, several Scottish Six Day Trials, three
World Trials championships, numerous International Six Day
Trials, several Welsh Three Day Trials, and was champion of
Britain eleven years in a row in an era when that meant more
than the world trials championship. All that was after he
gave up a decent road racing career.

What really hurt my feelings was that Sammy Miller was on
vacation and just enjoying the Colorado scenery, not trying
to show off by going fast. He just didn't know how to corner
as slowly as riders like me. When not rocketing between
sections on the two 20-mile daily loops, he spent so much
time chatting with observers that he ended up with 0.3
penalty points for being 3 minutes late the second day.

He also didn't know how to put his feet down. S. Miller won
that Ute Cup handily, losing only 16 marks on observation in
the obstacle sections, half as many as L. Leavitt, the best
U.S. rider at the time, with a score of 32.

C. Fogel disgraced the Don's Cycles team by losing 163
marks, but learned that he was actually nowhere near the
limits of his machine's cornering abilities.

Carl Fogel

Carl Fogel wrote:

A 200 pound (91kg) bicycle and rider coasting down an 8%
grade with the other defaults set reaches about 47 mph.
Adding 8 mph to reach 55 mph takes another 73 pounds (124kg
total). At such speeds, enormous force is needed to overcome
the wild increase of wind drag with each additional mile per
hour.

Based on personal experience, those speeds seem a little low. My
bike+rider weight is 165 lb, and I regularly exceed 50 mph on long
grades of 8%. That does require a pretty tight tuck, though.
--
terry morse Palo Alto, CA http://bike.terrymorse.com/

Carl Fogel wrote:

A 200 pound (91kg) bicycle and rider coasting down an 8%
grade with the other defaults set reaches about 47 mph.
Adding 8 mph to reach 55 mph takes another 73 pounds (124kg
total). At such speeds, enormous force is needed to overcome
the wild increase of wind drag with each additional mile per
hour.

Based on personal experience, those speeds seem a little low. My
bike+rider weight is 165 lb, and I regularly exceed 50 mph on long
grades of 8%. That does require a pretty tight tuck, though.
--
terry morse Palo Alto, CA http://bike.terrymorse.com/

Chalo wrote:

...
If a high center of gravity makes a pushbike harder to ride than a
motorbike, then why are tallbikes easier than regular bikes, all else
equal? And why are lowracer recumbents almost unridable for most
cyclists? You are simply mistaken about CoG and its relation to
difficulty....

Thanks for reminding me that my lowracer recumbent [1] is almost
unrideable. I have found steering and balance to be easy [2], even
when I was not functioning properly from heat exhaustion and hyponatremia.

As for my level of gross motor coordination, it is below average. I did
not learn to ride an upright bicycle until I was 9 years old, have
trouble riding most uprights hands off, and usually crash when trying to
do "simple" maneuvers such as hopping curbs on a MTB.

Chalo has obviously never had the good fortune to ride a lowracer
recumbent with proper steering setup and frame geometry.

[1] http://www.ihpva.org/incoming/2002/sunset/Sunset001.jpg .
[2] This includes my first ride on this particular bicycle.

--
Tom Sherman

Chalo wrote:

...
If a high center of gravity makes a pushbike harder to ride than a
motorbike, then why are tallbikes easier than regular bikes, all else
equal? And why are lowracer recumbents almost unridable for most
cyclists? You are simply mistaken about CoG and its relation to
difficulty....

Thanks for reminding me that my lowracer recumbent [1] is almost
unrideable. I have found steering and balance to be easy [2], even
when I was not functioning properly from heat exhaustion and hyponatremia.

As for my level of gross motor coordination, it is below average. I did
not learn to ride an upright bicycle until I was 9 years old, have
trouble riding most uprights hands off, and usually crash when trying to
do "simple" maneuvers such as hopping curbs on a MTB.

Chalo has obviously never had the good fortune to ride a lowracer
recumbent with proper steering setup and frame geometry.

[1] http://www.ihpva.org/incoming/2002/sunset/Sunset001.jpg .
[2] This includes my first ride on this particular bicycle.

--
Tom Sherman

On Tue, 31 Aug 2004 18:02:34 -0700, Terry Morse
wrote:

Carl Fogel wrote:

A 200 pound (91kg) bicycle and rider coasting down an 8%
grade with the other defaults set reaches about 47 mph.
Adding 8 mph to reach 55 mph takes another 73 pounds (124kg
total). At such speeds, enormous force is needed to overcome
the wild increase of wind drag with each additional mile per
hour.

Based on personal experience, those speeds seem a little low. My
bike+rider weight is 165 lb, and I regularly exceed 50 mph on long
grades of 8%. That does require a pretty tight tuck, though.

Dear Terry,

Here's another calculator that offers different details:

http://www.kreuzotter.de/english/espeed.htm

To see what it calculates for 8%, no pedalling, your weight,
and so forth, set the cadence and power to 0 and the slope
to -8 (not -0.08).

Then plug in your weight, the bike's weight, and your
height, and pick hands on the tops, hands on the drops,
triathalon, or superman for your position.

You can also pick slower tires (front or rear), different
altitudes, and unusual temperatures.

There's even a wind speed field, plus a calculation of the
effective frontal area to plug into the other calculator.

Plus it lets you pick God-fearing Anglo-American units
instead of ending up with bizarre meters per second results.

Best of all, there's a diagram-graph showing the speed
increase for adding watts of pedalling power, plus all sorts
of notes. (It doesn't show much belief in Trevor Jeffrey's 9
stone rider doing 200 rpm on a 10% descent and reaching 70
mph.)

I used 145 lbs of 67-inch Morse, 20 pounds of bicycle, and
hands on the drops--which produced 42.2 mph.

Improving your tuck to triathlon suggested 46.3 mph.

A superman position raises the estimate to 53.1 mph.

I'd guess either a greater than 8% grade, quite an
impressive tuck. a nice tailwind, or a combination of all
three and a fudge factor. (My advice is to go for the tuck
or the tailwind--you need 11% to roll 50 mph.)

In general, speed calculators give lower speed figures for
the same data than most posters on rec.bicycles.tech.
Naturally, I want to believe my fellow posters, but it's odd
how many of them have significantly superior aerodynamic
qualities and enjoy unfailing tailwinds downhill.)

Still, these calculators could be missing something, so I'm
always interested in high speeds on normal bicycles with
grades and weights.

So far, no one has wondered whether riding directly toward
the rising moon might give a tidal advantage.

My speedometer showed a hair under 44 mph down my daily hill
today, an increase of 5 mph that's a tribute to my athletic
prowess (hey, I had to climb the hill before I could coast
down it), my dignified heft (bicycle and rider remain around
220 pounds, a convenient 100kg), my brilliant imitation of
an egg on a bicycle seat (I peek over the bars with one
eye, keep one hand on the rear brake, the other along the
top tube gripping the stem, and do sillythings with my
feet), and--most of all--a lucky tailwind.

Cheers,

Carl Fogel

On Tue, 31 Aug 2004 18:02:34 -0700, Terry Morse
wrote:

Carl Fogel wrote:

A 200 pound (91kg) bicycle and rider coasting down an 8%
grade with the other defaults set reaches about 47 mph.
Adding 8 mph to reach 55 mph takes another 73 pounds (124kg
total). At such speeds, enormous force is needed to overcome
the wild increase of wind drag with each additional mile per
hour.

Based on personal experience, those speeds seem a little low. My
bike+rider weight is 165 lb, and I regularly exceed 50 mph on long
grades of 8%. That does require a pretty tight tuck, though.

Dear Terry,

Here's another calculator that offers different details:

http://www.kreuzotter.de/english/espeed.htm

To see what it calculates for 8%, no pedalling, your weight,
and so forth, set the cadence and power to 0 and the slope
to -8 (not -0.08).

Then plug in your weight, the bike's weight, and your
height, and pick hands on the tops, hands on the drops,
triathalon, or superman for your position.

You can also pick slower tires (front or rear), different
altitudes, and unusual temperatures.

There's even a wind speed field, plus a calculation of the
effective frontal area to plug into the other calculator.

Plus it lets you pick God-fearing Anglo-American units
instead of ending up with bizarre meters per second results.

Best of all, there's a diagram-graph showing the speed
increase for adding watts of pedalling power, plus all sorts
of notes. (It doesn't show much belief in Trevor Jeffrey's 9
stone rider doing 200 rpm on a 10% descent and reaching 70
mph.)

I used 145 lbs of 67-inch Morse, 20 pounds of bicycle, and
hands on the drops--which produced 42.2 mph.

Improving your tuck to triathlon suggested 46.3 mph.

A superman position raises the estimate to 53.1 mph.

I'd guess either a greater than 8% grade, quite an
impressive tuck. a nice tailwind, or a combination of all
three and a fudge factor. (My advice is to go for the tuck
or the tailwind--you need 11% to roll 50 mph.)

In general, speed calculators give lower speed figures for
the same data than most posters on rec.bicycles.tech.
Naturally, I want to believe my fellow posters, but it's odd
how many of them have significantly superior aerodynamic
qualities and enjoy unfailing tailwinds downhill.)

Still, these calculators could be missing something, so I'm
always interested in high speeds on normal bicycles with
grades and weights.

So far, no one has wondered whether riding directly toward
the rising moon might give a tidal advantage.

My speedometer showed a hair under 44 mph down my daily hill
today, an increase of 5 mph that's a tribute to my athletic
prowess (hey, I had to climb the hill before I could coast
down it), my dignified heft (bicycle and rider remain around
220 pounds, a convenient 100kg), my brilliant imitation of
an egg on a bicycle seat (I peek over the bars with one
eye, keep one hand on the rear brake, the other along the
top tube gripping the stem, and do sillythings with my
feet), and--most of all--a lucky tailwind.

Cheers,

Carl Fogel

"Callistus Valerius" writes:

But most bicycling does not involve the kind of braking and
cornering that's routine on motorcycles because most
bicycling takes place at only 10 to 20 mph.

Armstrong averages all of 25 mph for the whole Tour.


Are you riding your kids BMX bike on the little hill behind your house?
When I'm descending 8% grades, I sometimes pass motorcyclists at 55 mph.
Bicycling, like what we are talking in this newsgroup (not kids BMX bikes)
takes much more talent. For one, your center of gravity is so much higher
than on a motorcycle.

What does the height of the CG have to do with anything?