When to Stop Pedalling?

Discussion in 'Road Cycling' started by Elisa Francesca, Jun 16, 2003.

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  1. Hi, Me again.

    I was on this list in the winter when I had just started learning to bike, at age 46, very fat and
    an inveterate wearer of long skirts. You guys gave me some valuable tips about newbie cycling.

    As of a week ago, I started trying to get to work by bike. It still takes about 3 times longer than
    walking, with all the stops and starts. I'm way too terrified to cycle on the road but the sidewalks
    are too narrow for my lousy aim and full of jolting steps up and down. On the other hand, both

    pedestrians and motorists are quite indulgent these days because France is crippled by transport
    strikes, so all sorts of tentative cyclists are pulling their bikes out of mothballs and trying them
    in the wild again. It's a sort of Dunkirk Spirit.

    Anyway, here's my question. When going home I get a good stretch of downhill road. There comes a
    point where the pedalling starts to feel "empty", as if the chain had come unstuck. My instinct on
    these occasions is to assume I'm going too fast and start braking. Alternatively, if I gear up I
    sometimes get sensation back in the pedals.

    But I have seen people cycling downhill without pedalling at all, just resting their feet on the
    still pedals.

    Is that the thing to do? I don't like that sensation of empty pedalling and wonder what is causing
    it. I have the impression the bike is more unstable in that state.

    Thanks for your comments,

    Elisa Francesca Roselli, Paris, France
     
    Tags:


  2. Archer

    Archer Guest

    In article <[email protected]>,
    [email protected] says...

    ...

    > But I have seen people cycling downhill without pedalling at all, just resting their feet on the
    > still pedals.

    That's the normal way when you are going down a hill and can't pedal fast enough to keep up with it,
    or don't want to keep accelerating.

    >
    > Is that the thing to do? I don't like that sensation of empty pedalling and wonder what is causing
    > it. I have the impression the bike is more unstable in that state.

    It is. If your feet can't keep up with the bike's speed, either stop pedaling and coast, or shift to
    a higher gear and keep pedaling until you get to the speed you want. If you are going fast enough
    (however you define it), just coast. If you feel you are going too fast for comfort, start braking.

    --
    David Kerber An optimist says "Good morning, Lord." While a pessimist says "Good Lord,
    it's morning".

    Remove the ns_ from the address before e-mailing.
     
  3. Kirk Gordon

    Kirk Gordon Guest

    That "empty" pedal feeling is perfectly normal and natural. Your bike is just going fast enough down
    the hill that your combination of pedal speed and gear selection can't keep up with it. If you
    shifted to a higher gear, or pedaled faster, you'd eliminate the feeling; but you'd also be driving
    the bike faster and faster. To stop pedaling, and just let the bike coast, is also quite normal;
    It's also a good way to take a brief rest without having to get off the bike.

    There's nothing inherently unstable or unsafe about coasting, even on a nice long downhill run.
    What might be unsafe,however, is allowing the bike to run faster than your skill or comfort
    level can handle. In that case, brakes are the answer. Check them often, and make sure they're
    always in good condition.

    KG

    Elisa Francesca Roselli wrote:
    > Hi, Me again.
    >
    > I was on this list in the winter when I had just started learning to bike, at age 46, very fat and
    > an inveterate wearer of long skirts. You guys gave me some valuable tips about newbie cycling.
    >
    > As of a week ago, I started trying to get to work by bike. It still takes about 3 times longer
    > than walking, with all the stops and starts. I'm way too terrified to cycle on the road but the
    > sidewalks are too narrow for my lousy aim and full of jolting steps up and down. On the other
    > hand, both
    >
    > pedestrians and motorists are quite indulgent these days because France is crippled by transport
    > strikes, so all sorts of tentative cyclists are pulling their bikes out of mothballs and trying
    > them in the wild again. It's a sort of Dunkirk Spirit.
    >
    > Anyway, here's my question. When going home I get a good stretch of downhill road. There comes a
    > point where the pedalling starts to feel "empty", as if the chain had come unstuck. My instinct on
    > these occasions is to assume I'm going too fast and start braking. Alternatively, if I gear up I
    > sometimes get sensation back in the pedals.
    >
    > But I have seen people cycling downhill without pedalling at all, just resting their feet on the
    > still pedals.
    >
    > Is that the thing to do? I don't like that sensation of empty pedalling and wonder what is causing
    > it. I have the impression the bike is more unstable in that state.
    >
    > Thanks for your comments,
    >
    > Elisa Francesca Roselli, Paris, France
     
  4. Don Demair

    Don Demair Guest

    "Elisa Francesca Roselli" <[email protected]> wrote in message
    news:[email protected]...
    > Hi, Me again.
    >
    > I was on this list in the winter when I had just started learning to bike, at age 46, very fat and
    > an inveterate wearer of long skirts. You guys gave me some valuable tips about newbie cycling.
    >
    > As of a week ago, I started trying to get to work by bike. It still takes about 3 times longer
    > than walking, with all the stops and starts. I'm way too terrified to cycle on the road but the
    > sidewalks are too narrow for my lousy aim and full of jolting steps up and down. On the other
    > hand, both
    >
    > pedestrians and motorists are quite indulgent these days because France is crippled by transport
    > strikes, so all sorts of tentative cyclists are pulling their bikes out of mothballs and trying
    > them in the wild again. It's a sort of Dunkirk Spirit.
    >
    > Anyway, here's my question. When going home I get a good stretch of downhill road. There comes a
    > point where the pedalling starts to feel "empty", as if the chain had come unstuck. My instinct on
    > these occasions is to assume I'm going too fast and start braking. Alternatively, if I gear up I
    > sometimes get sensation back in the pedals.
    >
    > But I have seen people cycling downhill without pedalling at all, just resting their feet on the
    > still pedals.
    >
    > Is that the thing to do? I don't like that sensation of empty pedalling and wonder what is causing
    > it. I have the impression the bike is more unstable in that state.
    >
    > Thanks for your comments,
    >
    > Elisa Francesca Roselli, Paris, France
    >

    You may find that you feel a little more stable when coasting (not pedaling) if you take some of
    your weight off of the saddle by pressing on the pedals. This will give you 3 solid contact points
    with the bike (hands, seat and feet). Typically, I'll let one pedal drop to the bottom of the stroke
    (the "inside" pedal if turning, otherwise I alternate) and partially unweight myself from the saddle
    using that pedal just enough to sort of float over bumps in the road.

    Ride on, coast on occasion, Don
     
  5. Pbwalther

    Pbwalther Guest

    >'m way too terrified to cycle on the road but the sidewalks are too narrow for

    That is a pretty normal response when starting out. I would recommend you get a copy of Forester's
    "Effective Cycling" which I think is still in print. It is the best treatment I have ever seen to
    riding on the road.

    > so all sorts of tentative cyclists are pulling their bikes out of mothballs and trying them in the
    > wild again. It's a sort of Dunkirk Spirit.
    >

    Dunkirk Spirit? You lost me on that one. Dunkirk was where the English Army and part of the French
    army abandoned the fight in France and fled to England. They cleverly declared this a "victory". So
    are they all abandoning France?

    >There comes a point where the pedalling starts to feel "empty"

    Perfectly normal. Each gear will have a range of speed where it gives you power. You are just going
    too fast for that gear to have any effect so you don't feel any resistance.>

    My instinct on these occasions is to assume
    >I'm going too fast and start braking.

    Gosh, you sound even more cautious then I am. On steep hills cyclists can descend at speeds in
    excess of 40 or even 50 mph. I doubt that you are going more then half that speed. It is more a
    matter of where fear attacks you then physics and how quickly you might have to stop.

    >But I have seen people cycling downhill without pedalling at all, just resting their feet on the
    >still pedals.
    >

    Yes that is called "coasting". You can do one of 2 things. You can coast or you can stick the bike
    into its biggest gear and try to continue pedalling and increasing your speed. Coasting is
    perfectly ok.

    It used to be that bikes were direct drive. You could not coast. So if you went down a big hill,
    your speed was limited to how fast you could pedal (of course, cyclists did take their feet out of
    the pedals and just coast that way with little control). The freewheel was invented to allow
    coasting with one's feet on the pedals.

    > I have the impression the bike is more unstable in that state.

    Not at all. Gyroscopic forces give bikes increased stability at higher speeds. When you are going
    really slowly, it is rather easy to fall over, at high speeds you have quite a bit of stability.

    >Thanks for your comments,

    Actually, you are keenly observant and thoughtful. Interesting questions.
     
  6. Archer

    Archer Guest

    In article <[email protected]>, [email protected] says...

    ...

    > > I have the impression the bike is more
    > >unstable in that state.
    >
    > Not at all. Gyroscopic forces give bikes increased stability at higher speeds. When you are going
    > really slowly, it is rather easy to fall over, at high speeds you have quite a bit of stability.

    But if you are pedaling well above your comfortable cadence trying to keep up with the bike, it can
    be destabilizing. If you don't feel comfortable moving your legs that fast, you are definitely
    better off coasting.

    --
    David Kerber An optimist says "Good morning, Lord." While a pessimist says "Good Lord,
    it's morning".

    Remove the ns_ from the address before e-mailing.
     
  7. Thanks to everyone for their input on my question. I'll try coasting tonight and see how it feels.

    Cheers,

    Elisa Francesca Roselli, Paris, France
     
  8. Pbwalther wrote:

    > I would recommend you get a copy of Forester's "Effective Cycling" which I think is still in
    > print. It is the best treatment I have ever seen to riding on the road.

    I'll check it out on Amazon. Is it good for all countries and traffic regulations?

    > Dunkirk Spirit? You lost me on that one. Dunkirk was where the English Army and part of the French
    > army abandoned the fight in France and fled to England. They cleverly declared this a "victory".
    > So are they all abandoning France?

    It's just become a byword for a "drawing together and keeping your chin up in adversity" sort of
    thing. We've had strike after strike in the public transport systems. But I've never seen so many
    cyclists in the city (and rollerbladers, skateboarders, scooterists ...). The Mayor of Paris is
    also very cycle-friendly and with the global warming we will soon start having the pollution surges
    which give rise to prohibitions of car traffic. So it seems like the ZeitGeist is promoting cycling
    at the moment.

    > Gosh, you sound even more cautious then I am. On steep hills cyclists can descend at speeds in
    > excess of 40 or even 50 mph. I doubt that you are going more then half that speed. It is more a
    > matter of where fear attacks you then physics and how quickly you might have to stop.

    Indeed, fear attacks me very soon - I don't much like speed. I also think my brakes are up for
    servicing. They sing EEEAAYAEEAAYOH in a complaining but mighty contralto at every descent, take way
    too long for my comfort and then try to eject me forward onto the pavement. I've only had the bike
    since last fall, but I think I ride the brakes all the time. How often do the pads generally need to
    be changed?

    > Not at all. Gyroscopic forces give bikes increased stability at higher speeds. When you are going
    > really slowly, it is rather easy to fall over, at high speeds you have quite a bit of stability.

    That's what they all say. It may be elementary physics but it's hard to convince myself when it's me
    that's catapulting. Also I'm very bad at steering ...

    > Actually, you are keenly observant and thoughtful. Interesting questions.

    I never get over how nice people are in this forum. Do bicycles accelerate human evolution or
    something?

    Elisa Roselli Paris, France
     
  9. Todd Strong

    Todd Strong Guest

    [email protected] on Date: Mon, Jun 16, 2003 7:24 AM in Message-id:
    <[email protected]> wrote:

    ,snip>

    >Anyway, here's my question. When going home I get a good stretch of downhill road. There comes a
    >point where the pedalling starts to feel "empty", as if the chain had come unstuck. My instinct on
    >these occasions is to assume I'm going too fast and start braking. Alternatively, if I gear up I
    >sometimes get sensation back in the pedals.

    I'm curious as to where the hills around Paris are steep enough to experience this. Do you work at
    Sacre Couer? :)

    take care, Todd
     
  10. Jobst Brandt

    Jobst Brandt Guest

    Pb? Walther writes:

    > It used to be that bikes were direct drive. You could not coast. So if you went down a big hill,
    > your speed was limited to how fast you could pedal (of course, cyclists did take their feet out of
    > the pedals and just coast that way with little control). The freewheel was invented to allow
    > coasting with one's feet on the pedals.

    When was this? The freewheel was one of the earliest inventions after the chain driven Rover bicycle
    was introduced by Starley.

    >> I have the impression the bike is more unstable in that state.

    > Not at all. Gyroscopic forces give bikes increased stability at higher speeds. When you are going
    > really slowly, it is rather easy to fall over, at high speeds you have quite a bit of stability.

    Oh? Could you please explain how that occurs. You may have noticed that roller-blades are more
    stable at higher speeds exactly like ice skates. These are not Segways and do not use gyroscopic
    forces for stability. With increased speed stability improves from more rapid response to steering
    corrections.

    > Actually, you are keenly observant and thoughtful. Interesting questions.

    The answers were not equally keen.

    Jobst Brandt [email protected] Palo Alto CA
     
  11. Jacques

    Jacques Guest

    On Tue, 17 Jun 2003 17:08:48 +0200, Elisa Francesca Roselli wrote:

    >
    >
    > Pbwalther wrote:
    >
    >> I would recommend you get a copy of Forester's "Effective Cycling" which I think is still in
    >> print. It is the best treatment I have ever seen to riding on the road.
    >
    > I'll check it out on Amazon. Is it good for all countries and traffic regulations?
    >

    I just tried to order it from Amazon last week. They took my order but later replied that it was not
    available anymore.

    Jacques
     
  12. Wayne Menzie

    Wayne Menzie Guest

    [email protected] wrote in news:5rGHa.3197$%[email protected]:

    > You may have noticed that roller-blades are more stable at higher speeds exactly like ice skates.
    > These are not Segways and do not use gyroscopic forces for stability. With increased speed
    > stability improves from more rapid response to steering corrections.

    That has not been my experience. At least not with inline skates. Past a certain speed, the skates
    get very wobbly, most likely due to the rapid response to any change in direction. I understand that
    there is a definite increase in stability going from a dead stop to a reasonable cruising speed but
    that relationship does not appear to be linear.

    OK, I'll stop hijacking the thread now.

    --
    Wayne Menzie
     
  13. Kirk Gordon

    Kirk Gordon Guest

    [email protected] wrote:
    > Pb? Walther writes:
    >
    >>Not at all. Gyroscopic forces give bikes increased stability at higher speeds. When you are going
    >>really slowly, it is rather easy to fall over, at high speeds you have quite a bit of stability.
    >
    >
    > Oh? Could you please explain how that occurs. You may have noticed that roller-blades are more
    > stable at higher speeds exactly like ice skates. These are not Segways and do not use gyroscopic
    > forces for stability. With increased speed stability improves from more rapid response to steering
    > corrections.

    The wheels on a bicycle ARE gyroscopes, and stabilize the bike
    EXACTLY the way that any gyro will stabilize anything it's attached to.

    A Segway is inherently stable from side to side because it has two wheels on the same horizontal
    axle, with the center of mass (including the rider) located between the wheels. It therefore
    uses a gyro with a vertical axle, which resists front-to-back tipping. A bicycle is inherently
    stable in the fore and aft directions, because that's where the wheels are, and because the
    center of mass is also between the wheels. A bicycle needs to be protected from side-to-side
    tipping; and that protection (when the bike is moving fast enough) comes from the horizontal
    axles of the gyro-wheels. And, as with all gyroscopes, the faster the wheels rotate, the more
    stable they become. The Segway is different only in the fact that it has an ADDITIONAL gyroscope
    which is always moving at high speeds. A bicycle's gyros roll on the ground, so gyroscopic
    stability is directly proportional to speed of travel. A slow moving bicycle becomes unstable in
    exactly the way a Segway would if it's internal gyro were to slow down.

    The extent to which a gyroscope will produce stability depends on it's speed of rotation, and
    also on its "moment of inertia". Moment of inertia is what physicists call the combination of a
    spinning object's mass and the distance of its mass from the center of rotation. Basically, if
    two different size wheels had exactly the same mass, and were both rotating at the same RPM, the
    larger wheel would be a more effective gyro. Or, if the two wheels were the same diameter, and
    were moving at same RPM, the heavier wheel would be the better gyro. This means that very light
    bike wheels need to spin faster than heavy wheels, in order to create the same gyroscopic
    stability.

    More rapid response to steering at high speeds is not an improvement in stability. It's a mixed
    blessing with two kinds of effects. There is, of course, some minimum speed at which a steered
    vehicle doesn't operate very well. On boats, which need water flowing across their rudders, this
    is called "steerageway." On a car, obviously, you can turn the steering wheel all you want, and
    nothing will happen if the car isn't rolling. Keeping a bicycle upright when it's speed is too
    small to create gyroscopic stability requires that the front wheel be turned in the direction
    the bike wants to fall. If the wheel is rolling, this causes the wheels to move under the center
    of mass, and to recover (momentarily) verical balance. If the wheel is rolling very slowly, of
    course, then it will be slower to get back under the rider. This means that either the change in
    wheel direction must be more dramatic, or that the rider exercise more care to balance on his
    own, so that his/her center of mass doesn't get very far from the line between points where the
    wheels touch the ground.

    High speed, however, makes every little change in steering wheel direction, from any cause, have
    a more dramatic effect on the vehicle's direction of travel. To steer well and stably at high
    speed requires smaller, more subtle steering corrections than at low speed. It will also require
    more rapid and accurate response from the driver/rider to correct for changes in steering wheel
    direction that are cause by bumps, gravel, slopes in road surfaces, etc.

    When steering action is considered at both extremes of the speed range, it becomes clear that
    very fast isn't any better than very slow; and that the best speed (for steering purposes
    only) occurs at some moderate speed that's appropriate for an individual rider's sense of
    balance, reaction time, and skill with small adjustments on the handlebar. Very high speeds,
    without gyroscopic stabilization, are as much an enemy to effortless, carefree steering, as
    very low speeds.

    What makes a bike more stable AND easier to steer at high speeds is the fact that the
    gyroscopic action of the wheels provides increased resistance to tipping, so steering
    corrections for that purpose become smaller and less frequent. At the same time, the
    fast-spinning front wheel/gyro resists motion of any kind other than parallel to its axle, and
    therefore doesn't get bumped off course by road hazzards as easily as it would at lower speeds.
    It also requires the rider to exert more force on the handlebar before the wheel will change
    direction, which has the nice and convenient effect of dampening and minimizing the extent to
    which the front wheel CAN be turned, except when the rider makes a conscious effort to do so.
    To test this, of course, it's only necessary to sit up for a moment, and take your hands off
    the handlebar. Riding hands-free is tough to do at low speeds because there's nothing to keep
    the front wheel from wandering anywhere it wants to. The rider must continually shift his/her
    weight left and right, keeping the center of mass over the wandering wheels at all times. At
    higher speeds, however, the front wheel's gyroscopic action prevents it from wandering around,
    and keeps it rolling in a nice straight line. In this case, the rider must NOT shift weight, or
    the center of mass would move away from the center of the wheel line, and the front wheel would
    resist changing direction to correct.

    With regard to ice skates and roller blades: I'm not aware that these are more stable at high
    speeds. In fact, that seems very unlikely. If there is any truth to this idea, then it has
    nothing to do with a real increase in the stability of the skates or blades, but probably with
    the total momentum of the skater, and the increased inertial tendency to overcome the effects of
    small obstacles like pebles on a path, or divots in an ice surface. (The wheels on rollerblades
    are gyroscopes, too; but their diameters and masses are so small that they'd need to move at
    insane speeds before the effect could matter.) There is, like a bicycle, a quickened ability at
    high speeds for the skates to move back under the center of a skater's body when correction for
    balance is needed; but the problem of corrections needing to be more precise and subtle also
    applies. The result is the same mixed blessing described for bikes, above.

    What DOES make these devices more stable, in actual practice, is lengthening the blades. With
    one skate on each side (left and right) of his/her center of mass, a skater can easily control
    lateral stability with leg muscles. Front to back stability, however, is achieved by creating a
    longer footprint. That's also why skis are so long.

    KG
     
  14. Just Zis Guy

    Just Zis Guy Guest

    On Tue, 17 Jun 2003 21:53:01 +0200, "jacques" <[email protected]> wrote:

    >I just tried to order it from Amazon last week. They took my order but later replied that it was
    >not available anymore.

    Shame. Ask a Real Bookseller (TM) - they can often get stuff. Or maybe eBay for it, which is how I
    got my copy of Unsafe At Any Speed.

    Guy
    ===
    ** WARNING ** This posting may contain traces of irony. http://www.chapmancentral.com Advance
    notice: ADSL service in process of transfer to a new ISP. Obviously there will be a week of downtime
    between the engineer removing the BT service and the same engineer connecting the same equipment on
    the same line in the same exchange and billing it to the new ISP.
     
  15. Zoot Katz

    Zoot Katz Guest

    Tue, 17 Jun 2003 22:51:28 +0100, <[email protected]>, "Just zis Guy, you
    know?" <[email protected]> wrote:

    >On Tue, 17 Jun 2003 21:53:01 +0200, "jacques" <[email protected]> wrote:
    >
    >>I just tried to order it from Amazon last week. They took my order but later replied that it was
    >>not available anymore.
    >
    >Shame. Ask a Real Bookseller (TM) - they can often get stuff. Or maybe eBay for it, which is how I
    >got my copy of Unsafe At Any Speed.
    >
    >Guy
    www.abebooks.com has 28 listings for "Effective Cycling" with copies starting at $7.00
    --
    zk
     
  16. Robin Hubert

    Robin Hubert Guest

    <Appropriate top-posting>

    Oh, this is going to be good ....

    --
    Robin Hubert <[email protected]>

    "Kirk Gordon" <[email protected]> wrote in message news:[email protected]...
    > [email protected] wrote:
    > > Pb? Walther writes:
    > >
    > >>Not at all. Gyroscopic forces give bikes increased stability at higher speeds. When you are
    > >>going really slowly, it is rather easy to fall over, at high speeds you have quite a bit of
    > >>stability.
    > >
    > >
    > > Oh? Could you please explain how that occurs. You may have noticed that roller-blades are more
    > > stable at higher speeds exactly like ice skates. These are not Segways and do not use gyroscopic
    > > forces for stability. With increased speed stability improves from more rapid response to
    > > steering corrections.
    >
    > The wheels on a bicycle ARE gyroscopes, and stabilize the bike
    > EXACTLY the way that any gyro will stabilize anything it's attached to.
    >
    > A Segway is inherently stable from side to side because it has two wheels on the same
    > horizontal axle, with the center of mass (including the rider) located between the wheels. It
    > therefore uses a gyro with a vertical axle, which resists front-to-back tipping. A bicycle is
    > inherently stable in the fore and aft directions, because that's where the wheels are, and
    > because the center of mass is also between the wheels. A bicycle needs to be protected from
    > side-to-side tipping; and that protection (when the bike is moving fast enough) comes from the
    > horizontal axles of the gyro-wheels. And, as with all gyroscopes, the faster the wheels
    > rotate, the more stable they become. The Segway is different only in the fact that it has an
    > ADDITIONAL gyroscope which is always moving at high speeds. A bicycle's gyros roll on the
    > ground, so gyroscopic stability is directly proportional to speed of travel. A slow moving
    > bicycle becomes unstable in exactly the way a Segway would if it's internal gyro were to slow
    > down.
    >
    > The extent to which a gyroscope will produce stability depends on it's speed of rotation, and
    > also on its "moment of inertia". Moment of inertia is what physicists call the combination of
    > a spinning object's mass and the distance of its mass from the center of rotation. Basically,
    > if two different size wheels had exactly the same mass, and were both rotating at the same
    > RPM, the larger wheel would be a more effective gyro. Or, if the two wheels were the same
    > diameter, and were moving at same RPM, the heavier wheel would be the better gyro. This means
    > that very light bike wheels need to spin faster than heavy wheels, in order to create the same
    > gyroscopic stability.
    >
    > More rapid response to steering at high speeds is not an improvement in stability. It's a
    > mixed blessing with two kinds of effects. There is, of course, some minimum speed at which a
    > steered vehicle doesn't operate very well. On boats, which need water flowing across their
    > rudders, this is called "steerageway." On a car, obviously, you can turn the steering wheel
    > all you want, and nothing will happen if the car isn't rolling. Keeping a bicycle upright when
    > it's speed is too small to create gyroscopic stability requires that the front wheel be turned
    > in the direction the bike wants to fall. If the wheel is rolling, this causes the wheels to
    > move under the center of mass, and to recover (momentarily) verical balance. If the wheel is
    > rolling very slowly, of course, then it will be slower to get back under the rider. This means
    > that either the change in wheel direction must be more dramatic, or that the rider exercise
    > more care to balance on his own, so that his/her center of mass doesn't get very far from the
    > line between points where the wheels touch the ground.
    >
    > High speed, however, makes every little change in steering wheel direction, from any cause,
    > have a more dramatic effect on the vehicle's direction of travel. To steer well and stably at
    > high speed requires smaller, more subtle steering corrections than at low speed. It will also
    > require more rapid and accurate response from the driver/rider to correct for changes in
    > steering wheel direction that are cause by bumps, gravel, slopes in road surfaces, etc.
    >
    > When steering action is considered at both extremes of the speed range, it becomes clear that
    > very fast isn't any better than very slow; and that the best speed (for steering purposes
    > only) occurs at some moderate speed that's appropriate for an individual rider's sense of
    > balance, reaction time, and skill with small adjustments on the handlebar. Very high speeds,
    > without gyroscopic stabilization, are as much an enemy to effortless, carefree steering, as
    > very low speeds.
    >
    > What makes a bike more stable AND easier to steer at high speeds is the fact that the
    > gyroscopic action of the wheels provides increased resistance to tipping, so steering
    > corrections for that purpose become smaller and less frequent. At the same time, the
    > fast-spinning front wheel/gyro resists motion of any kind other than parallel to its axle, and
    > therefore doesn't get bumped off course by road hazzards as easily as it would at lower
    > speeds. It also requires the rider to exert more force on the handlebar before the wheel will
    > change direction, which has the nice and convenient effect of dampening and minimizing the
    > extent to which the front wheel CAN be turned, except when the rider makes a conscious effort
    > to do so. To test this, of course, it's only necessary to sit up for a moment, and take your
    > hands off the handlebar. Riding hands-free is tough to do at low speeds because there's
    > nothing to keep the front wheel from wandering anywhere it wants to. The rider must
    > continually shift his/her weight left and right, keeping the center of mass over the wandering
    > wheels at all times. At higher speeds, however, the front wheel's gyroscopic action prevents
    > it from wandering around, and keeps it rolling in a nice straight line. In this case, the
    > rider must NOT shift weight, or the center of mass would move away from the center of the
    > wheel line, and the front wheel would resist changing direction to correct.
    >
    > With regard to ice skates and roller blades: I'm not aware that these are more stable at high
    > speeds. In fact, that seems very unlikely. If there is any truth to this idea, then it has
    > nothing to do with a real increase in the stability of the skates or blades, but probably with
    > the total momentum of the skater, and the increased inertial tendency to overcome the effects
    > of small obstacles like pebles on a path, or divots in an ice surface. (The wheels on
    > rollerblades are gyroscopes, too; but their diameters and masses are so small that they'd need
    > to move at insane speeds before the effect could matter.) There is, like a bicycle, a
    > quickened ability at high speeds for the skates to move back under the center of a skater's
    > body when correction for balance is needed; but the problem of corrections needing to be more
    > precise and subtle also applies. The result is the same mixed blessing described for bikes,
    > above.
    >
    > What DOES make these devices more stable, in actual practice, is lengthening the blades. With
    > one skate on each side (left and right) of his/her center of mass, a skater can easily control
    > lateral stability with leg muscles. Front to back stability, however, is achieved by creating
    > a longer footprint. That's also why skis are so long.
    >
    > KG
     
  17. Hunrobe

    Hunrobe Guest

    >"Don DeMair" [email protected]

    wrote in part:

    >Typically, I'll let one pedal drop to the bottom of the stroke (the "inside" pedal if turning,
    >otherwise I alternate) and partially unweight myself from the saddle using that pedal just enough
    >to sort of float over bumps in the road.

    "Unweighting" the saddle is good but don't you mean the *outside* pedal?

    Regards, Bob Hunt
     
  18. On Tue, 17 Jun 2003 17:08:48 +0200 in rec.bicycles.misc, Elisa Francesca Roselli
    <[email protected]> wrote:

    > Indeed, fear attacks me very soon - I don't much like speed.

    you need to get over this irrational fear. bicycles are more stable at higher speeds due to the
    increased gyroscopic effect of the spinning wheels. OTOH, you have to watch more for hazards like
    loose gravel.

    but oh, the rush! my favorite downhill run is from the top of white pass into skagway, alaska --- 8
    miles from the top of the pass to customs.

    > I also think my brakes are up for servicing. They sing EEEAAYAEEAAYOH in a complaining but mighty
    > contralto at every descent, take way too long for my comfort and then try to eject me forward onto
    > the pavement. I've only had the bike since last fall, but I think I ride the brakes all the time.
    > How often do the pads generally need to be changed?
    >
    depends on how much you ride. when they wear enough that they are uneven, or get glazed, or when too
    much rubber wears off. ask at your local bike shop.

    learn how to adjust the brakes as your pads wear. find a bike maintenance book at your local library
    or bookstore. join your local bike club. take a class in bike maintenance and buy the few simple
    tools you need to do your own tuneups.
     
  19. On Tue, 17 Jun 2003 21:53:01 +0200 in rec.bicycles.misc, "jacques" <[email protected]> wrote:

    > >> I would recommend you get a copy of Forester's "Effective Cycling" which I think is still in
    > >> print. It is the best treatment I have ever seen to riding on the road.
    > >
    > > I'll check it out on Amazon. Is it good for all countries and traffic regulations?
    > >
    >
    > I just tried to order it from Amazon last week. They took my order but later replied that it was
    > not available anymore.
    >
    many new and used copies available at a real bookstore: http://www.powells.com
     
  20. Don Demair

    Don Demair Guest

    "Hunrobe" <[email protected]> wrote in message news:[email protected]...
    > >"Don DeMair" [email protected]
    >
    > wrote in part:
    >
    > >Typically, I'll let one pedal drop to the bottom of the stroke (the "inside" pedal if turning,
    > >otherwise I alternate) and partially unweight myself from the saddle using that pedal just enough
    > >to sort of float over bumps in the road.
    >
    > "Unweighting" the saddle is good but don't you mean the *outside* pedal?
    >
    > Regards, Bob Hunt

    Oops! Thanks for the correction.

    -Don
     
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