1,216 miles in a day
tal...@spanky.sps.mot.com
Following was reported in The Arizona Republic, Saturday, April 28, 1990.
Mike Secrest set a world record Friday, bicycling 1,216.81 miles in
24 hours.
Secrest, 37, pedaling in the draft of a tractor-trailer around a one-mile
oval at Phoenix International Raceway, averaged 50.66 mph...
The old motor-paced record for a bicycle in 24 hours was 860 miles at
38.5 mph, set in 1932 by Hubert Opperman of Sydney, Australia...
Steve Talent, Motorola Semiconductor Products Sector CAD
Mesa, AZ 602-994-6801, ...!{oakhill, sun!sunburn, uunet}!dover!talent
Les Earnest
>Mike Secrest set a world record Friday, bicycling 1,216.81 miles in
>24 hours.
>
>Secrest, 37, pedaling in the draft of a tractor-trailer around a one-mile
>oval at Phoenix International Raceway, averaged 50.66 mph...
Not at all remarkable. You see, we all travel about 1.6 million miles
every 24 hours with negligible effort because of the Earth's motion
around the Sun. This happens because the Earth sucks even better than
a tractor-trailer.
All motor-paced records are dreck.
--
Les Earnest Phone: 415 941-3984
Internet: L...@Sail.Stanford.edu USMail: 12769 Dianne Dr.
UUCP: . . . decwrl!Sail.Stanford.edu!Les Los Altos Hills, CA 94022
jobst_b...@hp1900.desk.hp.com
>...
>All motor paced records are derck.
Anyone who has ridden in a convertible car with the top down will
recall that your hair, if any, gets blown forward over your face.
It should be evident, 1) that with a suitable wind screen, air can
be turned around to blow in the direction of travel, 2) that records
are set behind windscreens that are designed to turn air around are
usd to push the rider, 3) that these record breakers often must
brake to avoid being pushed into the pacing vehicle, 4) that the
power required to spin bicycle wheels in still air at these record
speeds generally exceeds human ability by a large degree (see John
Howard's land speed record).
I am not impressed mainly because this record misrepresents bicycling
effort and is more a test of not falling off the bike than athletic
performance. I find it similarly significant to swallowing live
goldfish for the record.
Daniel Mocsny
>Les Earnest writes:
>>All motor paced records are derck.
Isn't that derckz, as in Emmy Derckz, the professional rider with
585 DNF's, five Tours-de-France Lanterne Rouge titles, and three
starting-line flats in the Worlds? The rider who proved that the
best way to set the Hour Record was to go to low altitude, where
the athlete can obtain a higher oxygen density, by building the
custom floating velodrome on the Dead Sea? And then motorpacing
after the officials on hand collapsed from heat stroke?
>Anyone who has ridden in a convertible car with the top down will
>recall that your hair, if any, gets blown forward over your face.
That all depends of course on where your date is sitting; if in your
lap, (s)he may disrupt the normal airflow to send this prediction
out the window (so to speak).
>I am not impressed mainly because this record misrepresents bicycling
>effort and is more a test of not falling off the bike than athletic
>performance. I find it similarly significant to swallowing live
>goldfish for the record.
The cycling record I want is to be the first human to attain
orbital velocity unaided on any celestial object with circular
cross-section and a diameter of 1500 km or more.
--
Dan Mocsny Snail:
Internet: dmo...@minerva.che.uc.edu Dept. of Chemical Engng. M.L. 171
dmo...@uceng.uc.edu University of Cincinnati
513/751-6824 (home) 513/556-2007 (lab) Cincinnati, Ohio 45221-0171
Alex Matthews
>In article <3231628...@HP1900UX.HPDESK> jobst_brandt%4...@hp1900.desk.hp.com writes:
>>I am not impressed mainly because this record misrepresents bicycling
>>effort and is more a test of not falling off the bike than athletic
>>performance. I find it similarly significant to swallowing live
>>goldfish for the record.
>
>The cycling record I want is to be the first human to attain
>orbital velocity unaided on any celestial object with circular
>cross-section and a diameter of 1500 km or more.
Interesting goal, but impossible if unaided. First, you need a bike.
Then, you are faced with the intractable physical problem of keeping
the rear wheel (or any wheel, for that matter) on the ground long
enough to accelerate you to escape velocity. Witness:
Escape velocity: V(esc) = sqrt(2GM/R),
where G=gravitational constant
M=mass of spherical celestial object
R=radius at surface.
sqrt() is the square root function.
Limiting velocity (velocity at which one's centripetal acceleration
overcomes surface gravity and one enters into low, not escape, orbit):
V(lim) = sqrt(GM/R).
The alert astrocyclist will note that the limiting velocity is down
a factor of root 2 from the desired escape velocity. So, Dan, you would
require the assistance of a grappling hook to make your wish come
true. Therefore, I am not impressed mainly because this record
misrepresents bicycling effort and is more a test of not falling off
the planet than athletic performance. I find it similarly significant
to swallowing live goldfish for the record.
Alex Matthews matt...@jila.bitnet | "...if you ride too good a horse
al...@lyra.colorado.edu | you will not take the straight
DoD #0010 '84 GS550ES, '81 GS450L | road to town."
'89 Trek 1200, '75 Nishiki Custom Sport | - Carl Sandberg
Daniel Mocsny
>In article <45...@uceng.UC.EDU> dmo...@minerva.che.uc.edu (Daniel Mocsny) writes:
>>The cycling record I want is to be the first human to attain
>>orbital velocity unaided on any celestial object with circular
>>cross-section and a diameter of 1500 km or more.
>
>Interesting goal, but impossible if unaided. First, you need a bike.
>Then, you are faced with the intractable physical problem of keeping
>the rear wheel (or any wheel, for that matter) on the ground long
>enough to accelerate you to escape velocity. Witness:
>
>Escape velocity: V(esc) = sqrt(2GM/R),
Uhm...I said, "orbital velocity." And I assumed I'd have a bike.
To overcome the centripetal acceleration problem, I had pictured
riding a rail-bike with opposing guide wheels. The bike would
probably best be a recumbent, so I could be well strapped in.
The obvious problems include (1) gearing for the enormously wide
speed range (I'd consider ejecting unneeded drivetrain components
as I crossed successive operating ranges); (2) building wheels,
etc., that could handle the high rotational velocities; and (3) the
power requirements of accelerating further when I'm already at
a high velocity. And also, I'd have to haul along enough mass to
keep me alive on an airless celestial body.
Elementary mechanics gives P=FV and F=mA. At a speed of 500 m/s,
if I could develop 200 W, then neglecting frictional losses I
would be exerting 200 (n m/s)/500 (m/s) = 0.4 n of force against
the rail. This would give me the whopping acceleration of
0.4 n / 200 kg = 0.004 m/s^2. (I assume my bike, space suit, and
me will mass 200 kg.) That's going to mean a lot of effort to
tick the Avocet up to the next speed. It also means even feeble
frictional losses could end the whole show.
At 500 m/s, my kinetic energy would be (1/2) m V^2 = 2.5e+6 J.
One Power Bar yields 600 kJ, so that's about four Power Bars.
(Of course, I'm only about 0.3 efficient at converting chemical
energy into mechanical work, so I'd need to eat about 13 of them.)
Assuming a steady output of 200 W, I'd need 12,500 s to build
up this mechanical energy (assuming no friction). That's almost
four hours of steady pounding. Interesting to imagine by the
end of 100 mile hammer ride, I've dissipated enough energy to
be traveling as fast as a high-performance jet fighter...No
wonder I'm tired.
If anyone wants to discount my efforts (I can picture Axel Merckx
sniffing at my moon-circling rail with, "At least *I* rode a bike"),
well, the centripetal acceleration problem could be overcome by
constructing the celestial equivalent of an ultra-high speed
velodrome. A very *large* circular crater would do nicely if we
polished off the walls to form banking with smoothly increasing
slope. Using a large enough radius would let me crank steadily
up to orbital velocity, at which point I would simply steer up
the banking slightly and sail off into space. I'd need an
escape ramp to guide me to a graceful exit, because if I tried
to just fall over the top of the banking I might very well
scrape it along the way, giving me enough road rash to deflate
the whole scheme.
Les Earnest
>All motor paced records are derck.
To which Dan Mocsny responds:
>Isn't that derckz, as in Emmy Derckz, the professional rider with
>585 DNF's, five Tours-de-France Lanterne Rouge titles, and three
>starting-line flats in the Worlds? . . .
Er, ah, actually I meant to type "dreck" but had a fit of digital
dyslexia.
Jim Scandale
>Quoting a newspaper article, Steve Talent writes:
>>Mike Secrest set a world record Friday, bicycling 1,216.81 miles in
>>24 hours.
>>
>>Secrest, 37, pedaling in the draft of a tractor-trailer around a one-mile
>>oval at Phoenix International Raceway, averaged 50.66 mph...
>
>Not at all remarkable. You see, we all travel about 1.6 million miles
>every 24 hours with negligible effort because of the Earth's motion
>around the Sun. This happens because the Earth sucks even better than
>a tractor-trailer.
>
>All motor-paced records are dreck.
Last fall, I rode a local 20k time trial in 19 min 30 sec by drafting
behind my Plymouth mini-van (rear door open). The hardest part of the
effort was finding a chainring big enough. The tricky part was doing the
start, finish and turn-around alone and getting "picked-up" by the van
at the appropriate points.
This is a local 'record' for the 20k but nobody recognizes it
as such. Of course, I didn't have the advantage of a tractor-trailor
to draft. I had a good laugh at the posted 'record' and the mental
picture of a full-sized tractor-trailor going around the Phoenix
car-racing oval. If I could stay awake long enough, I could probably
set some sort of record too (presuming I had something big enough to
follow).
David Keppel
>[1945 km/day; motorpaced]
>I am not impressed mainly because this record misrepresents bicycling
>effort and is more a test of not falling off the bike than athletic
>performance. I find it similarly significant to swallowing live
>goldfish for the record.
I assure you that riding a motorcycle half that distance in one day can
be fatiguing. My impression from a writeup of John Howard's salt-flat
motorpace was that it was a serious workout. I agree that it is hardly
athletic performance in the normal sense, but I disagree that it is a
test of not falling off the bike.
;-D on ( Someday: Tomoato paced ) Pardo
--
pa...@cs.washington.edu
{rutgers,cornell,ucsd,ubc-cs,tektronix}!uw-beaver!june!pardo
Harry Phinney
> motorpace was that it was a serious workout.
I'm sure it was hard, but it pales before some of the _real_ cycling
records. Around 1970 a guy named Roy Cromack (sp?) rode about 510
miles in 24 hours. Unpaced. With round spokes (i.e. a real bike) and
wool jersey(s). You've never heard of him? This is undoubtably because
he didn't employ Ken Souza's press agent.
Harry Phinney ha...@hp-pcd.cv.hp.com
Pamela Wybieracki
>In article <1990Apr30....@Neon.Stanford.EDU> l...@Gang-of-Four.Stanford.EDU (Les Earnest) writes:
>>Quoting a newspaper article, Steve Talent writes:
>>>Mike Secrest set a world record Friday, bicycling 1,216.81 miles in
>>>24 hours.
>>>
>>>Secrest, 37, pedaling in the draft of a tractor-trailer around a one-mile
>>>oval at Phoenix International Raceway, averaged 50.66 mph...
>>
>>
>If I could stay awake long enough, I could probably
>set some sort of record too (presuming I had something big enough to
>follow).
OK, Then stop talking about it and do it. I am constantly amazed at the number
of articles I read here, where someone says, hey, that's no big deal. I could
do that. Then let's see you do it.
I personally am VERY IMPRESSED with this record and all the others Mike Secrest
has set in is career, along with most of the other pros and record setters
that have been the topics of these sorts of discussions. I have a great deal
more respect for someone who actually *DOES* something, than those who sit
back in their easy chairs making negative comments about it.
BTW, I have ridden for 24 hours straight - no drafting allowed,
mountainous terrain, cold rainy weather - 300.3 miles ( for second
place - women, 1988 New York Challenge )
Pamela Blalock Wybieracki pam...@camex.com (try it)
Camex, Inc. !husc6!lloyd!pamela
75 Kneeland St., Boston, MA 02111 Tel: (617) 426-3577
George Scott
>> My impression from a writeup of John Howard's salt-flat
>> motorpace was that it was a serious workout.
>> ;-D on ( Someday: Tomoato paced ) Pardo
>I'm sure it was hard, but it pales before some of the _real_ cycling
>records. Around 1970 a guy named Roy Cromack (sp?) rode about 510
>miles in 24 hours. Unpaced. With round spokes (i.e. a real bike) and
>wool jersey(s).
Another early-70s 24-hour man was an Englishman named Nat Carline or something
like that. He did a few 500+ mile rides, mostly in the New Forest (rolling
hills). He was famous for using only 2 gears, a 108-inch for cruising, and a
102-inch for when the going got tough.
--
-------------------------------------------------------------------------------
George N. Scott EMAIL: geo...@wind55.seri.gov
Wind Research Branch. VOICE: 303-231-7667
Solar Energy Research Institute 1617 Cole Blvd., Golden, CO 80401-3393
Pamela Wybieracki
Hmm, The book I have here at work is only through 1985, but the records it
shows are as follows:
24-hour outdoor track (solo-unpaced)
5/23/81 Lon Haldeman 392.1 miles
9/22/81 Lon Haldeman 454.2 miles
4/02/84 Jim Elliot 502.3 miles
I'm sure the record had been bested since then. I'll try to find my latest
UMCA record book tonight. The UMCA differentaites between track and road
records. I'll look for the road records too. They also have categories
for man/women, unpaced, paced (by another bicycle), motor-paced, tandem, etc.
BTW, these records were listed in the book *Sport Cycling* by Michael
Shermer, another great ultra-marathon cyclist.
jobst_b...@hp1900.desk.hp.com
claim that the 1,216 mile truck paced record is a commendable
achievement. As is often the case in these disagreements, it is
easier to argue off the subject than to refute the statements made.
Music critics needn't be composers of respected music, just as
those who do not think riding behind a windscreen to set bicycle
records is an athletic event needn't set records.
The records cited are certainly athletic records and they are also
not motor paced. I think it was clearly stated that:
> All motor-paced records are dreck.
Therefore, let me review what I believe these motor paced events
have become in contrast to the un-paced records.
John Howard's ride was, in fact, riding a thin tired motorcycle
with indirect drive over a measured course. His "bicycle" had the
throttle control on the bars and he drove the pace car by remote
control while his feet were attached to pedals, pedals whose speed
was governed by a chain. The speed of the wheels had little to do
with the pedals since the ratio was so high that it prevented
overcoming just the rolling resistance, quite aside from wind drag
in the rotating wheels.
No chainwheel large enough would fit between the rider and the
ground so a double reduction was used. The cadence was prescribed
by the throttle control in his hand rather than power from the
pedals. In his case, staying upright was the primary problem
according to the reports. The man who tried to beat this record
using the same equipment failed by not being able to stay on the
bike. The danger in this event was probably higher than the 24 hr
record.
Thus the 24 hour record is similar to riding an over-powered moped
with thin tires for 24 hours. Meanwhile the pedals were rotated at
some credible looking cadence since pedaling did not propel the
bicycle. I am sure that I could not begin to match this performance
because I am probably physically unable to, and mentally because I
find it a meaningless record.
Harry Phinney
> UMCA record book tonight. The UMCA differentaites between track and road
> records. I'll look for the road records too.
Well, I'm sure the UMCA wasn't around in 1970 to observe and verify old
Roy's record, but I guess I trust the British TT people about as much.
I'll look in my ancient Ron Kitching catalogue to refresh my memory on
the details of Roy's ride. His ride was definitely on the road, not
track.
Harry Phinney ha...@hp-pcd.cv.hp.com
PS: I'm definitely impressed with your 300+ miles in 24 hours. I've
never attempted a 24hr TT, as I was put off of long distance rides by a
foolish ~230 mile endeavor the day after Christmas when I was 19 years
old. It took me around 16 hours, and I was _wasted_ by the end.
Jim Scandale
>
>John Howard's ride was, in fact, riding a thin tired motorcycle
>with indirect drive over a measured course. His "bicycle" had the
>throttle control on the bars and he drove the pace car by remote
>control while his feet were attached to pedals,
>
Actually, he didn't use the remote throttle control when setting
the record. It proved too hard to use in practice.
> The cadence was prescribed
>by the throttle control in his hand rather than power from the
>pedals.
>
Again, this isn't true.
>Thus the 24 hour record is similar to riding an over-powered moped
>with thin tires for 24 hours. Meanwhile the pedals were rotated at
>some credible looking cadence since pedaling did not propel the
>bicycle. ^^^^^^^^^^^^^^^^^^^^^^^
I don't understand how this can be true. I don't for a minute,
believe that the bicycle is "sucked along" by the motor vehicle.
Please explain!
Keith Erskine
>OK, Then stop talking about it and do it. I am constantly amazed at the number
>of articles I read here, where someone says, hey, that's no big deal. I could
>do that. Then let's see you do it.
>I personally am VERY IMPRESSED with this record and all the others Mike Secrest
>has set in is career, along with most of the other pros and record setters
>that have been the topics of these sorts of discussions. I have a great deal
>more respect for someone who actually *DOES* something, than those who sit
>back in their easy chairs making negative comments about it.
Thanks, Pam. I couldn't agree more.
> Pamela Blalock Wybieracki pam...@camex.com (try it)
>----------
more bs from
Keith Erskine
jobst_b...@hp1900.desk.hp.com
> I don't understand how this can be true. I don't for a minute,
> believe that the bicycle is "sucked along" by the motor vehicle.
> Please explain!
Scientifically speaking, air pushes rather than sucks. In either
case, whether it sucks or pushes, the power of a bicycle rider is
not enough to overcome rolling resistance at speeds over 100 mph
especially with the gear ratio used by Howard. The power required
to spin spoked wheels is substantially more. The forward turbulence,
in the report I read, in which Howard also described the throttle
on the bicycle, was such that the bike was difficult to control.
As I stated, the man who tried to beat Howard's record could not
control the bike and crashed, ending his challenge.
If the pace vehicle were not pushing the rider along, why have a
pace vehicle. You might suggest that this serves to carry a
windstill envelope, but this is not enough to set such records.
If this were so, roller records (equally strange) would be set
at equally high speeds. Behind a windscreen wind must push
forward by the laws of fluids. The eddies have strong forward
components and these, as I mentioned, are glaringly evident in
a convertible car with the top down. I don't recall what the
gear ratio on the Howard machine was but I recall that it was
greater than a chainwheel three feet in diameter. This ratio, as
I recall defies just moving the bike by the pedals, much less
riding at any speed (even with no air drag).
Note, all hatchback cars and station wagons have either a rear
window wiper or a dirty window or both because the forward draft
blows dirt and grime onto the back. Highway trucks and busses have
the same problem. I don't know what other examples to give you to
explain the strong forward pressure behind a windscreen. I'm sure
that you could find flow diagrams in any fluids text for flow behind
a blunt body.
jobst_brandt@hplabs,hp,com
Steve Rader
>
>> I don't understand how this can be true. I don't for a minute,
>> believe that the bicycle is "sucked along" by the motor vehicle.
>> Please explain!
>
>
>Scientifically speaking, air pushes rather than sucks. In either
>case, whether it sucks or pushes,
The air does 64% of the work at 25mph behind a truck with cap.
(See this month's Bicycling.) So this guy did about 30% of the work
to go _50mph_. This may not be exactly like going 15mph for 24 hours
but I'd guess it's close. I still think this is an amazing feat.
Just think about doing a 40mph desent for hours on end.
So what's the 24 hour record for non-drafted cycling anyway?
steve ra...@shorty.cs.wisc.edu
Frank Ball
*> I don't understand how this can be true. I don't for a minute,
*> believe that the bicycle is "sucked along" by the motor vehicle.
*> Please explain!
*Scientifically speaking, air pushes rather than sucks. In either
I have read about Allan Abbots 138 mph record (the one before John
Howards) that he set around '75. He was at Bonneville salt flats
drafting behind an old Chevy drag racer with a what looked like a
toolshed bolted to the back of it to make a windbrake for the bicycle.
There were two people in the car. One faced forwards and steered.
The other faced backwards and worked the trottle.
He had a huge gear, but not as high as John Howards. He had to be
towed up to 70 mph, then he pedaled after that. Once up to high
speed a problem started. He dropped back a little too far
behind the pace car. The wind swirling behind the car then shoved
him forwards, causing him to run into the back of the car. This
made him drop back again. The process repeated. Wind pushing forwards.
Slam. Bounce back. ..... There was a special "bumper" on the car
and bike so that he didn't lose it when this happened. All this while
spinning 165 or so rpm and the back end of the car was fishtailing
back and forth because the salt doesn't have very good traction, and
the car was anything but areodynamic, and the car had no rear suspension;
so they were having trouble keeping the car under control. Sounds
like fun?
The first "motor paced" record that I am aware of was by "mile a minute
Murphy" in the 1890's. They put wooden boards down between the rails
of a train track. Murphy rode behind a train and reached 60 mph.
I guess it took longer than they planned to get upto speed, because
they were almost at the end of the boards and still going full speed.
So they reached over the railing on the back of the train car and pulled
him in. The back of the train had some extra sides and top added to
shield Murphy from the wind. He also had the same problem of slamming
into the back of the pace vehicle after the wind shoved him forwards.
*Note, all hatchback cars and station wagons have either a rear
*window wiper or a dirty window or both because the forward draft
*blows dirt and grime onto the back. Highway trucks and busses have
*the same problem. I don't know what other examples to give you to
*explain the strong forward pressure behind a windscreen. I'm sure
*that you could find flow diagrams in any fluids text for flow behind
*a blunt body.
*
*jobst_brandt@hplabs,hp,com
----------
Other examples. Don't drive a station wagon with the back window open:
if you do it blows your own exhaust in the back window. Ride a motorcycle
with a tall windscreen. On some bikes the rider or passenger will find
the wind pushing their head FORWARDS.
Frank Ball fra...@hpsad.HP.COM
John F. Haugh II
>Note, all hatchback cars and station wagons have either a rear
>window wiper or a dirty window or both because the forward draft
>blows dirt and grime onto the back. Highway trucks and busses have
>the same problem. I don't know what other examples to give you to
>explain the strong forward pressure behind a windscreen. I'm sure
>that you could find flow diagrams in any fluids text for flow behind
>a blunt body.
The forward pressure behind a tractor trailer is strong enough
to pull a motorcycle along at 70MPH with trottle at almost an
idle. You have to get very close, which is very scary ...
I don't know how much I agree with the assertion that there is
sufficient suction to completely pull the rider with no effort
on his part, but I will agree that the suction is quite
considerable. It isn't simply a still wind envelope.
--
John F. Haugh II UUCP: ...!cs.utexas.edu!rpp386!jfh
Ma Bell: (512) 832-8832 Domain: j...@rpp386.cactus.org
Daniel Mocsny
>The forward pressure behind a tractor trailer is strong enough
>to pull a motorcycle along at 70MPH with trottle at almost an
>idle. You have to get very close, which is very scary ...
>
>I don't know how much I agree with the assertion that there is
>sufficient suction to completely pull the rider with no effort
>on his part, but I will agree that the suction is quite
>considerable. It isn't simply a still wind envelope.
Last year I drafted a semi-truck along a stretch of highway that has
(according to my topo map) a 100 ft elevation gain in just under 1/2
mile. I pedaling my 52x12 at what felt to me like an uncomfortably
high RPM. My effort level was close to maximal, especially at the
base of the hill where the driver was gunning the engine coming out
of a turn. But I stayed with the truck all the way to the crest,
where I slowed to wait for my riding partners (yes, they were impressed).
I suspect that suction was involved. I don't see how I could
turn such a gear up this hill even with a tailwind strong enough to
reduce my airspeed to zero. Nonetheless, staying with the truck
was like riding a very hard interval, especially because I never
motorpace directly behind an unfamiliar vehicle. I always line up on the
left side where I can see ahead.
I am surprised to hear that Jobst is not impressed by motorpacing.
It would seem to be a skill-oriented athletic achievement on par
with descending, which I know Jobst enjoys. In each case, something
other than the rider's immediate output does the work, both demand
highly developed skills, and both are quite dangerous and thrilling.
jobst_b...@hp1900.desk.hp.com
let me say this about that, as our one time president used to
say. Motor paced records are set behind vehicles that have fairly
complete wind protection. There is no blast of air coming under
the vehicle as with a conventional highway vehicle because there
is a complete skirt that shuts off to the roadway. By this absence
of fill air from under the vehicle, air from above and the sides
is "drawn" into the space behind the vehicle such that it strikes
the rider only from behind.
The closest to a record breaking motor pace to be found on the
road is a low tailgate moving-van with about six inch clearance
or a city bus with a full tailend mud flap (used here to keep oil
drops from the engine from splattering on following cars). Both of
these allow considerable leakage and yet, on the flat, one can coast
behind them if speed is high enough. The problem is getting up to
speed to catch the draft. Howard got a tow.
Don't for a moment assume that the effect is constant or linear with
speed. As with most air drag matters, I am sure this goes more like
the square of velocity. There is no push at zero speed while the
push is violent at 60 mph as you can discover on a motorcycle.
Thomas A. Fine
>to pull a motorcycle along at 70MPH with trottle at almost an
>idle. You have to get very close, which is very scary ...
>
>I don't know how much I agree with the assertion that there is
>sufficient suction to completely pull the rider with no effort
>on his part, but I will agree that the suction is quite
>considerable. It isn't simply a still wind envelope.
If your at almost idle, you are coasting against the engine, which has a
very large amount of friction drag. Pull in the clutch next time and see
what happens. I've heard that most bikes will keep up.
Also, motorcycles have considerably more wheel bearing friction than bicycles
do (if both are typical bikes).
I consider it an amazing feat, even an amazing feat on a bicycle, but not an
amazing cycling feat.
>John F. Haugh II UUCP: ...!cs.utexas.edu!rpp386!jfh
>Ma Bell: (512) 832-8832 Domain: j...@rpp386.cactus.org
tom
Daniel Mocsny
>I consider it an amazing feat, even an amazing feat on a bicycle, but not an
>amazing cycling feat.
I got a chance to ride with John Howard when he was in Cincinnati
for a seminar. He impressed me as being an extremely personable and
easy-going fellow. He has the most amazingly scarred legs I have
ever seen. He also has about 1,000,000 stories, all interesting,
to tell from his long racing career.
One of the things we talked about on the ride was his motorpaced
record. He claimed that the effort required was equivalent to the
hardest pursuit ride he had ever done.
Blair P. Houghton
>sufficient suction to completely pull the rider with no effort
>on his part, but I will agree that the suction is quite
>considerable. It isn't simply a still wind envelope.
After a rainstorm in AZ (where it gets amazingly clear
amazingly soon after an amazingly wet downpour) I observed
water kicked up by semi- trailers being sucked _upward_ and
_forward_ to the top of the trailer (I couldn't see if it
actually touched the trailer at the top, but it sure headed
that way).
This made a D-shaped loop of heavy-dropletted mist at the
back of the truck, about five feet deep at its deepest
point. Water farther behind the truck was also moving
forward, but fell to the ground.
I was watching while driving in a parallel lane going the
same direction as the truck and about a hundred feet away,
perpendicularly, and the water was silhouetted against a
clear sky. No, I was _not_ watching where I was going;
this was SCIENCE, dammit, and I wanted to be sure of what I
was seeing.
Someone should attach anemometers to a bike and trail
a truck to see what's going on, here.
--Blair
"I want a show of hands..."
Harry Phinney
> Yes, it is an accomplishment, a testament to stamina, etc. But has anyone
> given thought to the amount of pollutants this "tractor-trailer" emitted
> while proving the metle of a man?
> And for what? Shame on all associated with such activities!
What about football games that tens of thousands of people drive to?
What about bicycle races that virtually all competitors drive to?
What about century rides that many participants drive to, and which
provide support vehicles? Should we all be ashamed of taking part in
such degrading activities? In addition, the manufacture of bicycles is
hardly a clean procedure. Bikes use petroleum products, the output of
dirty steel mills, and are often coated with paints which utilize
isocyanates (remember Bohpal, India?).
Harry Phinney ha...@hp-pcd.cv.hp.com