Getting Started on Rollers

Ron Ruff said:

dvt said:

Kinetic energy for linear motion is (mv^2)/2. For rotational energy, as
in the wheels spinning, the energy is (Iw^2)/2, where I is the
rotational inertia and w is the angular velocity.

Do you realize that this is exactly the same? Iw^2/2 is just the
kinetic energy equation written in polar coordinates.

I hadn't thought of it that way. Now that you point it out, the mass of
rim/tyre/tubes/tape are all traveling at 40 mph or slightly less in the
scenario presented. Yes, that would have been easier to calculate.

Quoted message said:

But we already
know that the only velocity that matters is at the rim/tire... and we
know that speed. You've gone to a lot of extra trouble to calculate the
same thing.

Alfred Rider had the right idea, and the equation reduces to:
V= v*(m/M)^.5

He used the mass of the entire wheel (including hubs) traveling at 40
mph. That's why he came up with a much higher estimate than I.

Quoted message said:

Quoted message said:

Summary: I disagree with your physics, but my conclusion is the same.

Quoted message said:

Guess again.

If Alfred and I used the same physics, how do you figure that we came up
with different answers? We can't both be right.

--
Dave
dvt at psu dot edu

dvt said:

He used the mass of the entire wheel (including hubs) traveling at 40
mph. That's why he came up with a much higher estimate than I.

If Alfred and I used the same physics, how do you figure that we came up
with different answers? We can't both be right.

His final calculation was rims and tires, etc weight of 1540g (3.38lb),
and 20mph speed, 175lb rider:

20*(3.38/175)^.5= 2.78mph

At 40mph it would be double... 5.56mph

Using your numbers, 1000g (2.2lb, too low BTW), 40mph, 175lb rider:

40*(2.2/175)^.5= 4.48mph ... which is different than what you got. I
don't know why. Maybe a conversion factor was wrong, or some other
error? That's why it is good to simplify and use dimensionless ratios
before calculating... if possible.

Jenko said:

Michael Press said:

Kinetic energy in two wheels:
2 * I * w^2 / 2 = 450 J

Does the front wheel spin as fast as the rear wheel?

Jenko, never used a roller

Yes, they're connected by a belt.

"Kurgan Gringioni" <[email hidden]> wrote in message

Quoted message said:

Dumbass -

The record for "roller beers" at UC San Diego is 106 minutes @ 1 oz.
beer/minute courtesy of "The Loafmeister" aka. Dave Schurig.

Most people don't make it past 40 minutes.

One beer=12 ounces, so that's not very many beers although the 106
minute one is pretty impressive (almost 9 beers). He threw up all over
the place afterwards.

That's a hell of an effective way to pass the time on rollers. What about
bathroom breaks?

John Forrest Tomlinson said:

Mad Dog said:

I was still pedaling intentionally (to generate the
7' skid mark), adding enough energy to the system to completely swamp your
flawed model. But if you look back, I never claimed a velocity and never
insinuated that it was like being shot out of a cannon.

WTF???

You're an idiot.

Give the guy some credit. Strange things happen sometimes.

Like once, I was riding on my rollers. I was using a time trial
crankset with a 55 chainring (I was awaiting the return my lightweight
carbon crank from the shop that was painting "Chubby Poser" in gothic
script on the arms) and I was using incredibly heavy tires. Specialized
Turbo Armadillos, I think.

I got spinning up to a bit over 300 rpm and, wouldn't you know it, I
popped off the side. The angular momentum from the wheels, um, ripped
a hole in the fabric of the space-time continuum. Really! Don't you
hate it when that happens?

Oh, come on! It did too, and I can prove it!

Many interesting things happened that day. Among them, the Al Gore from
an alternate universe was pulled through the hole along with the Eric
Cartman (of "South Park" fame) from a similar universe. The two were
fused together to form a single individual in our world.

Come on, you know THIS is true! There is no other rational explanation
for Tom Kunich.

[email hidden] says...

Quoted message said:

Unfortunately, I am a minion. The way modern scientific
research goes, you spend a long time as a minion, in order
that by the time you graduate to having minions of your own,
you're burnt out and bitter enough to treat them like galley
slaves, and so the cycle of life continues. It's how the
traditions of the field are passed down.

I can't believe they got you to swallow that. Some day, you'll ask for your
spot on the throne and they will laugh and tell you you're too old to lead. Go
for it while you have a chance, dude. Can't fight against the youth.

It's just a funny song. Plus I can see my obituary

Quoted message said:

now: "Area Man Falls Down Basement Stairs, Dies,
Attempting To Find Bike Rollers While [censored]."
Boy, it's a good thing I don't have a basement!
Life is too short to miss out on overconsumption just
because of the fear of accidental death.

Your humor bone resonates. That's healthy.

Tim Lines said:

Give the guy some credit. Strange things happen sometimes.

Like once, I was riding on my rollers. I was using a time trial
crankset with a 55 chainring (I was awaiting the return my lightweight
carbon crank from the shop that was painting "Chubby Poser" in gothic
script on the arms) and I was using incredibly heavy tires. Specialized
Turbo Armadillos, I think.

I got spinning up to a bit over 300 rpm and, wouldn't you know it, I
popped off the side. The angular momentum from the wheels, um, ripped
a hole in the fabric of the space-time continuum. Really! Don't you
hate it when that happens?

Oh, come on! It did too, and I can prove it!

Many interesting things happened that day. Among them, the Al Gore from
an alternate universe was pulled through the hole along with the Eric
Cartman (of "South Park" fame) from a similar universe. The two were
fused together to form a single individual in our world.

Come on, you know THIS is true!

Yeah, come to think of it a few years ago I was getting toward the end
of a medium distance (six-hour) roller ride. In the dark. Listening
to Inagaddadavida by Iron Butterfly. Of course.

Anyway, the stims I'd taken at the end of hour 4 started to kick in,
and I was groovin. With a lot of panache. Hard, like 450 watts for
40 minutes straight. NUMbers don't lie BTW.

So when my wife peeled me off the rollers after my 360 minutes were
up, I couldn't stop pedalling. Had to go to bed on my back with my
feet in the air. For real. And when I woke up I'd pedalled off the
bed and up teh side of my armoir. 4 feet up. For real. Numbes don't
lie.

JT

****************************
Remove "remove" to reply
Visit http://www.jt10000.com
****************************

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

Quoted message said:

George Mueller said:

Quoted message said:

Where is Jobst Brandt when you need him?

Quoted message said:

He's probably riding to the beach, like I did today.

Californians

Quoted message said:

Quoted message said:

don't need no steenking rollers... Predicted 75F tomorrow.

See you

Quoted message said:

Quoted message said:

in San Gregorio!

Quoted message said:

Well that was last week via Big Basin redwoods and Gazos Creek

in

Quoted message said:

wonderful fall weather. This Sunday it was Mt. Hamilton where
beautiful fall foliage was augmented by a herd of a dozen adult

wild

Quoted message said:

pigs (shoot then varmints) in Grant Park and scores of turkeys

from

Quoted message said:

the San Jose hills to Livermore. Among other wildlife, on two
occasions, a Roadrunner crossed in front of us and stood there

long

Quoted message said:

enough for us to appreciate its beautiful plumage. They did

not say

Quoted message said:

"mbeep beep". A flock of about 100 migrating Canada Geese were
waiting for sunset to continue their trek as they ate grass on

the

Quoted message said:

lawns of the large office center with the geyser like fountain

at the

Quoted message said:

west end of Livermore.

Quit gloating. -- Jay Beattie.

P.S., I imagine that suburbia has crept up the sides of the
mountain since I left 20 years ago, at least to that first
plateau on the west side.

Mad Dog said:

Carl Sundquist says...

Quoted message said:

Apparently you did not understand the previous post. It said
_no_forward_momentum_. Nothing about continuing to apply power.

It also said nothing about NOT continuing to apply power.

Quoted message said:

Case closed.

Decades ago.

There is no Latin translation for "no forward momentum", since Isaac
Newton hadn't done that yet...

Mad Dog said:

Carl Sundquist says...

Quoted message said:

Apparently you did not understand the previous post. It said
_no_forward_momentum_. Nothing about continuing to apply power.

It also said nothing about NOT continuing to apply power.

Quoted message said:

Case closed.

Decades ago.

There is no Latin translation for "no forward momentum", since Isaac
Newton hadn't done that yet...

Carl Sundquist said:

Quoted message said:

The record for "roller beers" at UC San Diego is 106 minutes @ 1 oz.
beer/minute courtesy of "The Loafmeister" aka. Dave Schurig.

One beer=12 ounces, so that's not very many beers although the 106
minute one is pretty impressive (almost 9 beers).

That's a hell of an effective way to pass the time on rollers. What about
bathroom breaks?

Exactly, because otherwise, I accept the challenge.

--
E. Dronkert

Quoted message said:

Unfortunately, I am a minion. The way modern scientific
research goes, you spend a long time as a minion, in order
that by the time you graduate to having minions of your own,
you're burnt out and bitter enough to treat them like galley
slaves, and so the cycle of life continues. It's how the
traditions of the field are passed down.

Don't worry, be happy that there still are some scientific jobs worse than
yours:
http://www.popsci.com/popsci/science/806ffb24a5f27010vgnvcm1000004eecbccdrcrd.html

Quoted message said:

Unfortunately, I am a minion. The way modern scientific
research goes, you spend a long time as a minion, in order
that by the time you graduate to having minions of your own,
you're burnt out and bitter enough to treat them like galley
slaves, and so the cycle of life continues. It's how the
traditions of the field are passed down.

Don't worry, be happy that there still are some scientific jobs worse than
yours:
http://www.popsci.com/popsci/science/806ffb24a5f27010vgnvcm1000004eecbccdrcrd.html

John Forrest Tomlinson said:

So when my wife peeled me off the rollers after my 360 minutes were
up, I couldn't stop pedalling. Had to go to bed on my back with my
feet in the air. For real. And when I woke up I'd pedalled off the
bed and up teh side of my armoir. 4 feet up. For real. Numbes don't
lie.

You should get heather to help spice up your bedroom scene writing.

Stu Fleming says...

Quoted message said:

There is no Latin translation for "no forward momentum", since Isaac
Newton hadn't done that yet...

Hey, Newton was a pretty cool guy. Ever read any of his philosophical musings?

Tim Lines said:

John Forrest Tomlinson said:

Mad Dog said:

I was still pedaling intentionally (to generate the
7' skid mark), adding enough energy to the system to completely swamp your
flawed model. But if you look back, I never claimed a velocity and never
insinuated that it was like being shot out of a cannon.

WTF???

You're an idiot.

Give the guy some credit. Strange things happen sometimes.

Like once, I was riding on my rollers. I was using a time trial
crankset with a 55 chainring (I was awaiting the return my lightweight
carbon crank from the shop that was painting "Chubby Poser" in gothic
script on the arms) and I was using incredibly heavy tires. Specialized
Turbo Armadillos, I think.

I got spinning up to a bit over 300 rpm and, wouldn't you know it, I
popped off the side. The angular momentum from the wheels, um, ripped
a hole in the fabric of the space-time continuum. Really! Don't you
hate it when that happens?

Oh, come on! It did too, and I can prove it!

Many interesting things happened that day. Among them, the Al Gore from
an alternate universe was pulled through the hole along with the Eric
Cartman (of "South Park" fame) from a similar universe. The two were
fused together to form a single individual in our world.

Come on, you know THIS is true! There is no other rational explanation
for Tom Kunich.

I can believe everything, except the part about actually getting
Armadillos to fit in your frame. That's a bit of a stretch for me.

Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...

William Asher said:

"In what
police investigators can only conclude was an auto-erotic episode gone
awry, a local man wearing lycra shorts and a punk-rock t-shirt was found
dead at the bottom of a stairway after neighbors complained of a bad smell
coming from the home.

Wrong. A roadie smells better after just lying around decomposing for
three days. The neighbors might have noticed the improvement.

Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...

On Tue, 15 Nov 2005 18:04:22 -0600, "Carl Sundquist" <[email hidden]>

Quoted message said:

That's a hell of an effective way to pass the time on rollers. What about
bathroom breaks?

Beer bottle and a smooth spin?

Curtis L. Russell
Odenton, MD (USA)
Just someone on two wheels...

Ewoud Dronkert said:

Carl Sundquist said:

Quoted message said:

The record for "roller beers" at UC San Diego is 106 minutes @ 1 oz.
beer/minute courtesy of "The Loafmeister" aka. Dave Schurig.

One beer=12 ounces, so that's not very many beers although the 106
minute one is pretty impressive (almost 9 beers).

That's a hell of an effective way to pass the time on rollers. What about
bathroom breaks?

Exactly, because otherwise, I accept the challenge.

You keep the empty beer cans for a purpose, you know.
I learned that at Glasgow Rangers games in the 1980s.

Mad Dog said:

Stu Fleming says...

Quoted message said:

There is no Latin translation for "no forward momentum", since Isaac
Newton hadn't done that yet...

Hey, Newton was a pretty cool guy. Ever read any of his philosophical musings?

I got a copy from Seattle Public Library once but the important pages
were stuck together.