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Thread: how much

  1. #1
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    how much

    how much easier is it to pedal when you cut your bike weight 3 pounds??? How about 4 pounds???

    can you really feel the difference.....
    Last edited by SHIVER ME TIMBERS; 01-19-2005 at 10:20 AM.
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  2. #2
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    Quote Originally Posted by SHIVER ME TIMBERS
    how much easier is it to pedal when you cut your bike weight 3 pounds??? How about 4 pounds???

    can you really feel the difference.....
    any clues
    the trick is ENJOYING YOUR LIFE EACH DAY, don't waste them away wishing for better days

  3. #3
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    freshman phsyics 101:
    once you're moving.... NONE. Assuming you're not accellerating, weight does not make a difference. BUT, the problem here is friction on your tires from the ground. Incidently, assume you're gliding down a hill, a heavier bike will maintain speed better since it has more momentum.

    Anyway.... the problem is that maintain a speed you have to continue pedaling to conteract friction slowing you down. Then you're working against angular momemtum (i.e the weight of the suff you have to rotate, cranks, wheels, tires) to apply the force to maintain your speed.

    Of course when you're accelerating (which tends to happen alot in small amounts, since no one can maintain a perfectly steady speed) you have to apply more force for a heavier bike (F = M*A).

    So to answer your question, in an ideal environment it IS NOT easier to pedal a lighter bike, assuming that the tires and cranks weigh the same

  4. #4
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    analyticcycling.com

    Quote Originally Posted by SHIVER ME TIMBERS
    how much easier is it to pedal when you cut your bike weight 3 pounds??? How about 4 pounds???

    can you really feel the difference.....
    fill in the parameters and see the result!
    http://analyticcycling.com/ForcesLessWeight_Page.html

  5. #5
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    http://analyticcycling.com/WheelsClimb_Page.html

    that is specifically for wheel weight, but you can also change the bike weight and a whole lot of other variables.

    ill give you an example. this is on road though..
    last year, there was a hill climb race. i ended up finishing second in my category, U17 expert. the guy who won it was over a minute ahead of me, 1:18 to be exact, but, the difference between our bikes is huge. he has a 19lb wilier with 1330g am classic sprint 350's, and i have a 15 year old, 24lb cannondale with tank wheels.
    so, first i made everything even. wheel inertia, wheel weight and everything else.
    then i went downstairs, weight my front wheel (complete with skewer, rim tape, tube and tire) it came to 1480g lol. so then i just guessed that my rear would be about 1630g. his am classic spring 350's with 100g tubes (estimate) and 175g tires (the top maxxis tires) was 850 and 1050g. then i figured out that w/o wheels, our bike weights were 7.97 and 6.8 kg. i changed the ending time to 2100second, the air pressure to 1kg/m3, slope to 12% and distance to 8km (the actual grade and distance of the race).
    it made an 82s difference!! bigger than i wouldve thought.. and that doesnt include the fact that i outweigh him by 40lbs lol
    that example does use a lot of extremes though, but it should give you the idea
    (8) climb hard or never be seen (8)

  6. #6
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    Quote Originally Posted by SHIVER ME TIMBERS
    how much easier is it to pedal when you cut your bike weight 3 pounds??? How about 4 pounds???

    can you really feel the difference.....
    I think it is a noticeable difference when you get on a bike with 3-4lbs taken off it. Particularly if it is with the wheels etc where weight was saved.

    It may be harder to notice on a downhill bike though, with all that suspension bouncing away underneath you.
    Trev!

  7. #7
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    Quote Originally Posted by Trevor!
    I think it is a noticeable difference when you get on a bike with 3-4lbs taken off it. Particularly if it is with the wheels etc where weight was saved.

    It may be harder to notice on a downhill bike though, with all that suspension bouncing away underneath you.
    I am droping little over a pound in tires and 1 3/4 with seat and seat post...the DH bike weighed 43.5 when I started the diet
    the trick is ENJOYING YOUR LIFE EACH DAY, don't waste them away wishing for better days

  8. #8
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    Quote Originally Posted by SHIVER ME TIMBERS
    I am droping little over a pound in tires and 1 3/4 with seat and seat post...the DH bike weighed 43.5 when I started the diet
    I doubt you will notice much difference at all going from 43+ pounds to 41.
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  9. #9
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    thanks
    the trick is ENJOYING YOUR LIFE EACH DAY, don't waste them away wishing for better days

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