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  1. #1
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    Climbing on 10% gradient for 15 km...

    Sometimes, when I'm climbing in 10% to 15% gradient, how much power do I need for 12 km/h ? How can I maintain / train my breath ?
    I lose my breath if it's long long long climb ...

    Anyone has same experience with me...how to overcome that ?

  2. #2
    bas
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    Quote Originally Posted by bianchi77
    Sometimes, when I'm climbing in 10% to 15% gradient, how much power do I need for 12 km/h ? How can I maintain / train my breath ?
    I lose my breath if it's long long long climb ...

    Anyone has same experience with me...how to overcome that ?
    practice? lower gearing?

    what gearing you using??

  3. #3
    sometimereader
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    Quote Originally Posted by bianchi77
    Sometimes, when I'm climbing in 10% to 15% gradient, how much power do I need for 12 km/h ? How can I maintain / train my breath ?
    I lose my breath if it's long long long climb ...

    Anyone has same experience with me...how to overcome that ?
    If you can climb even a 10k 10% hill at 10 km/hr, you're a much stronger rider than me. In other words, you should expect to be exhausted by trying what you suggest.

    (There are various formulas that show what your vertical climbing rate should be (on steep hills) for a given aerobic capacity. Maybe you can find them.)
    Hard work pays off in the future. Laziness pays off now.
    -- Steven Wright

  4. #4
    Now with a 5900SL P1
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    Power required depends on your weight. Using one calculator for a 10% grade you would need between 300-360 watts depending if your weight is between 150 and 200 lbs to maintain 12 kph. Those numbers become 450-575 watts at 12kph if the grade becomes 15%.

    Those are pretty high sustained watts. I think that kind of effort makes the best of riders hurt.

  5. #5
    Now with a 5900SL P1
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    Quote Originally Posted by sometimerider
    If you can climb even a 10k 10% hill at 10 km/hr, you're a much stronger rider than me. In other words, you should expect to be exhausted by trying what you suggest.

    (There are various formulas that show what your vertical climbing rate should be (on steep hills) for a given aerobic capacity. Maybe you can find them.)
    +1. That climb would have me puking a lung by 3k's.

  6. #6
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    Quote Originally Posted by bas
    practice? lower gearing?

    what gearing you using??
    Yes practicing

    Gear 39-23

    What do you thing of it ?

  7. #7
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    Quote Originally Posted by sometimerider
    If you can climb even a 10k 10% hill at 10 km/hr, you're a much stronger rider than me. In other words, you should expect to be exhausted by trying what you suggest.

    (There are various formulas that show what your vertical climbing rate should be (on steep hills) for a given aerobic capacity. Maybe you can find them.)
    Where can I find the formula ?
    Or what kind of tool that I can use ? How much ?

  8. #8
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    Quote Originally Posted by 99trek5200
    Power required depends on your weight. Using one calculator for a 10% grade you would need between 300-360 watts depending if your weight is between 150 and 200 lbs to maintain 12 kph. Those numbers become 450-575 watts at 12kph if the grade becomes 15%.

    Those are pretty high sustained watts. I think that kind of effort makes the best of riders hurt.
    I'm 61 kg my bike is around 7-8 kg..

  9. #9
    wim
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    Quote Originally Posted by bianchi77
    Where can I find the formula ?
    This "Dr. Lim" formula seems to work pretty well:

    bike + rider weight (in kg) x 9.8 x elevation gain (in meters)
    divided by
    time (in seconds) = power (in watts).
    add 10% for rolling- and air resistance to fine-tune the watt number.

  10. #10
    toomanybikes
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    It is very unlikely you are going to find a road with 10 or 12 % grades for any sustained length of time, certainly not for 10 or 12 KM.

    While it is probable there are places where the road will pitch up to 10 or 12 % over its length, it is not likely to maintain that for more than a few yards at a time.

  11. #11
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    If you are climbing a 10-15% gradient in a 39-23, there is nothing wrong with your breathing. You are a world class cycler. Mt Washington averages 12% for 7.6 miles and I doubt anyone does it in a 39-23.

    b21

  12. #12
    Cpark
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    Quote Originally Posted by barry1021
    If you are climbing a 10-15% gradient in a 39-23, there is nothing wrong with your breathing. You are a world class cycler. Mt Washington averages 12% for 7.6 miles and I doubt anyone does it in a 39-23.

    b21
    +1.
    Lower gearing might help.
    Maybe 39-25 or 27?

  13. #13
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    Quote Originally Posted by bianchi77
    Where can I find the formula ?
    Or what kind of tool that I can use ? How much ?
    Here is a link to a calculator for you:

    http://bikecalculator.com/veloUS.html

  14. #14
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    Quote Originally Posted by toomanybikes
    It is very unlikely you are going to find a road with 10 or 12 % grades for any sustained length of time, certainly not for 10 or 12 KM.

    While it is probable there are places where the road will pitch up to 10 or 12 % over its length, it is not likely to maintain that for more than a few yards at a time.
    There is the Mont du Chat starting from Le Bourget du Lac (near Aix-les-Bains), France 13.5km for 1264m, for 9.4% average. There has been a race there in early July for the last 7 years, course record 48:30. The race is open to all, no license required. Most of the profile is given here: http://www.climbbybike.com/climb.asp...ountainID=6925 I don't think it's ever been used in the Tour de France, I don't know about other professional races.

    -ilan
    Last edited by ilan; 07-31-2008 at 09:44 AM.

  15. #15
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    Quote Originally Posted by cpark
    +1.
    Lower gearing might help.
    Maybe 39-25 or 27?
    More like 34x27 which is about 70 rpm for 11kph.

    -ilan

  16. #16
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    Ventilation is not a limiting factor in output so your breath is the last thing to worry about. Even at your highest (max) workload you will still be exhaling o2. To increase a sustainable workload you must increase your lactate threshold (t-vent) by training by using interval and tempo workouts

  17. #17
    Impulse Athletic Coaching
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    Quote Originally Posted by barry1021
    If you are climbing a 10-15% gradient in a 39-23, there is nothing wrong with your breathing. You are a world class cycler. Mt Washington averages 12% for 7.6 miles and I doubt anyone does it in a 39-23.

    b21
    Not true. Many people can do much harder, it's just that cadence suffers. I've done 16% grade (spikes to 24%) for ~2mi on 39x25. A 39x23 is only a difference of 2rpm. 36 vs 34rpm.

    It sucks a lot, but it's not impossible. A friend did it in his 42x25. 12% actually doesn't sound that bad after that.

  18. #18
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    Quote Originally Posted by iliveonnitro
    Not true. Many people can do much harder, it's just that cadence suffers. I've done 16% grade (spikes to 24%) for ~2mi on 39x25. A 39x23 is only a difference of 2rpm. 36 vs 34rpm.

    It sucks a lot, but it's not impossible. A friend did it in his 42x25. 12% actually doesn't sound that bad after that.
    Gino Bartali won the 1938 Tour de France riding up the Tourmalet (a dirt road at the time) in a 46x19 (approximately 39x17). Those were the days....

    -ilan
    Last edited by ilan; 07-31-2008 at 02:52 PM.

  19. #19
    sometimereader
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    Quote Originally Posted by bianchi77
    I'm 61 kg my bike is around 7-8 kg..
    Lightweight, huh? Ok, per the bikecalculator site, for you to do 12 km/hr up a 15 km 15% grade would require 380 watts for 73 minutes. World class.

    To do 10 km/hr on a 10 km 10% grade requires 212 watts for an hour. Doesn't sound like much, but I couldn't do it. (I would require 270 watts, since I weigh more.)

    Climbing on 10% gradient for 15 km...-bc.jpg
    Hard work pays off in the future. Laziness pays off now.
    -- Steven Wright

  20. #20
    Lurkaholic
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    Quote Originally Posted by toomanybikes
    It is very unlikely you are going to find a road with 10 or 12 % grades for any sustained length of time, certainly not for 10 or 12 KM.

    While it is probable there are places where the road will pitch up to 10 or 12 % over its length, it is not likely to maintain that for more than a few yards at a time.
    Come and visit the Alps buddy. France, Switzerland, Italy and Austria all have a few mountain passes that would easily fit this criteria. Try THIS RIDE in Italian-speaking Switzerland...averages 9.7% over 15km.
    "It takes two to lie, one to lie and one to listen" Homer J. Simpson

  21. #21
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    Quote Originally Posted by sometimerider
    Lightweight, huh? Ok, per the bikecalculator site, for you to do 12 km/hr up a 15 km 15% grade would require 380 watts for 73 minutes. World class.

    To do 10 km/hr on a 10 km 10% grade requires 212 watts for an hour. Doesn't sound like much, but I couldn't do it. (I would require 270 watts, since I weigh more.)

    Click image for larger version. 

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    Thanks for the info...
    It's very usefull, I guess it can be used as a reference on the trainer bike...
    but I don't have a heavy trainer that able to simulate a climbing road...
    and precisely know how much power do I dissipate....

  22. #22
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    Quote Originally Posted by wim
    This "Dr. Lim" formula seems to work pretty well:

    bike + rider weight (in kg) x 9.8 x elevation gain (in meters)
    divided by
    time (in seconds) = power (in watts).
    add 10% for rolling- and air resistance to fine-tune the watt number.
    Dude..that's not Dr. Lim's formula..

    That's the formula for potential energy..then you divide it by change in time to get power.

    P=F*h
    F = Force in Newtons, F = m*a, a = 9.8m/s^2, m = total weight of you and your bike in kg

    7-10% for rolling /air resistance sounds about right since you won't be traveling at high speeds so air resistance won't be huge but I'm guessing you're going to be losing a significant amount of energy in frame flex.

  23. #23
    So. Calif.
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    Concerning the estimation of human power output from hill climbing data, and specifically "add 10% for rolling- and air resistance to fine-tune the watt number" , I am wondering if the +10% value is perhaps too conservative.

    From the tire rolling resistance data at http://www.biketechreview.com/tires/AFM_tire_crr.htm ,
    a typical Michelin Pro3 Race tire consumes about 15 watts per wheel.
    That's on a smooth roller at 25 MPH.

    Furthermore, they claim "Crr on typical road surfaces may be 50 to 100 % higher".
    Let's say 50% more, on a typ asphalt road.
    That's 44 watts for 2 tires - a lot of rolling resistance! (at 25 mph).

    Power consumption due to tires likely depends on speed in some way -- but I don't know the details. For car tires, at least, the roll resistance Crr seems fairly constant out to about 50 mph (ref: http://www.greenhybrid.com/discuss/f...sistance-16474 )

    44 watts per 2 tires is about 10% of a competitive racer's output (~ 400 W ?), but it's closer to 20% for a fit recreational cyclist (~200 W ?).

    Does this seem reasonable ??



  24. #24
    Lexicon Devil
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    Quote Originally Posted by bianchi77
    Thanks for the info...
    It's very usefull, I guess it can be used as a reference on the trainer bike...
    but I don't have a heavy trainer that able to simulate a climbing road...
    and precisely know how much power do I dissipate....

    If you want to know how much power you're generating, you need to get a powermeter. I think we went over this in some other thread. These calculators are good for making rough estimates, but they're kinda worthless.

  25. #25
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    about the interval and tempo workouts...is there any methods or ways that work effectively and efficiently in a short time ? I don't have plenty of time for it

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