Is there a chart of watts + speed?

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Comments

  • Sutton_Rider
    Sutton_Rider Posts: 493
    Why is this sooooo difficult? There is a single answer. Assuming everything remains the same the only difference is: No wind and 10mph wind.
  • craigus89
    craigus89 Posts: 887
    Sutton Rider wrote:
    Why is this sooooo difficult? There is a single answer. Assuming everything remains the same the only difference is: No wind and 10mph wind.

    Imposter just answered that specifically. There is no way to know as the effect will be more or less depending on your position even if that position doesn't change.

    Imagine you had a parachute on your back. There would be a difference in watts required to maintain say 30kph between no wind and riding into 10mph headwind.

    Now imagine someone in a good TT position. There would also be a difference in watts required to maintain 30kph between no wind and riding into 10mph headwind.

    Do you think that difference would be the same?
  • Sutton_Rider
    Sutton_Rider Posts: 493
    It's obvious that riding into a headwind would require more watts / power to maintain a given speed than with no headwind. We can introduce all sorts of other variables along the way, but that would just cloud the answer. The question is somewhat hypothetical. What would the difference be in extra power required to maintain a given speed (in this case 16mph) with and without a 10mph headwind? No other factors need to be taken into account.
  • craigus89
    craigus89 Posts: 887
    Sutton Rider wrote:
    It's obvious that riding into a headwind would require more watts / power to maintain a given speed than with no headwind. We can introduce all sorts of other variables along the way, but that would just cloud the answer. The question is somewhat hypothetical. What would the difference be in extra power required to maintain a given speed (in this case 16mph) with and without a 10mph headwind? No other factors need to be taken into account.

    If you really don't understand this then read this:

    https://www.grc.nasa.gov/www/k-12/airplane/drageq.html
  • Sutton_Rider
    Sutton_Rider Posts: 493
    You're looking far to deeply. For the purpose of my question it doesn't matter if we are riding at the international standard atmosphere for density, temperature and pressure etc. or I'm wearing a skin suit or its Tuesday afternoon. Given all other factors are the same, approximately how much extra power would be required to ride at a given speed (16mph) into a 10mph headwind against no wind? Would we be looking at approx. 10%, 20%, 60%? Is there some sort of approximation / rule of thumb as there is that to ride at 16mph requires about 100 watts.
  • craigus89
    craigus89 Posts: 887
    Sutton Rider wrote:
    You're looking far to deeply. For the purpose of my question it doesn't matter if we are riding at the international standard atmosphere for density, temperature and pressure etc. or I'm wearing a skin suit or its Tuesday afternoon. Given all other factors are the same, approximately how much extra power would be required to ride at a given speed (16mph) into a 10mph headwind against no wind? Would we be looking at approx. 10%, 20%, 60%? Is there some sort of approximation / rule of thumb as there is that to ride at 16mph requires about 100 watts.

    You didn't read it then? To boil it down massively it is largely dependant on the size of the object moving into the wind i.e the rider. So if it were a big person with an upright position it would be a lot more in percentage terms than someone skinny in a low position.

    You do the math. I'm sure you could google it if you're that bothered and find some kind of test that was done by cycling weekly or something as equally unhelpful.
  • imposter2.0
    imposter2.0 Posts: 12,028
    Sutton Rider wrote:
    Why is this sooooo difficult? There is a single answer. Assuming everything remains the same the only difference is: No wind and 10mph wind.

    There is no 'universal' effect of a 10mph (or any other mph) headwind. The effect will depend entirely on your profile - which will be different for every rider. Possibly you are the one who is finding it 'sooooo difficult'....
  • Sutton_Rider
    Sutton_Rider Posts: 493
    I give up. YOU clearly don't understand my hypothetical question.
  • shirley_basso
    shirley_basso Posts: 6,195
    Scroll to about half way down here (to Richmond Park) and read to the end.

    http://www.slidingseat.net/cycling/cycling.html
  • imposter2.0
    imposter2.0 Posts: 12,028
    Sutton Rider wrote:
    I give up. YOU clearly don't understand my hypothetical question.

    We are discussing a physical effect (with an infinite number of variables) - not a hypothetical one. You are right to give up.
  • chris_bass
    chris_bass Posts: 4,913
    Sutton Rider wrote:
    I give up. YOU clearly don't understand my hypothetical question.

    I fear your hypothetical question is unable to be answered.

    10mph will affect an aero bike much more than a less aero one.

    you may need 10% more power on one and 20% more on the other, air acts more like a fluid the faster you go, so 10mph wind at 10mph ground speed wouldn't be the same as 10mph wind at 20mph ground speed.

    etc
    www.conjunctivitis.com - a site for sore eyes
  • jgsi
    jgsi Posts: 5,062
    Times have moved on....
    Does not Best Bike Split attempt to do this (at a cost) for testers and trumfalumps?
    Course upload, stick your 'variables' in and voila , hold that sh it for x amount of mins/hours for each sector.
  • craigus89
    craigus89 Posts: 887
    Sutton Rider wrote:
    I give up. YOU clearly don't understand my hypothetical question.

    Oh I see now, its hypothetical. It will take you an extra 28.3 watts.

    Hope that clears things up for you.
  • Sutton_Rider
    Sutton_Rider Posts: 493
    Thank you Craigus89, can I ask you where or how you came up with that number?
  • imposter2.0
    imposter2.0 Posts: 12,028
    Sutton Rider wrote:
    Thank you Craigus89, can I ask you where or how you came up with that number?

    Whoosh :lol:
  • ddraver
    ddraver Posts: 26,699
    SR - a tip from a non-mathmatical person who is occasionally forced to do maths - try and write out what you think the equation to work out you question would be.
    We're in danger of confusing passion with incompetence
    - @ddraver
  • chris_bass
    chris_bass Posts: 4,913
    have a go with this!

    http://kreuzotter.de/english/espeed.htm
    www.conjunctivitis.com - a site for sore eyes
  • Sutton_Rider
    Sutton_Rider Posts: 493
    Thanks Chris, I'll play with some numbers tomorrow.
  • Vino'sGhost
    Vino'sGhost Posts: 4,129
    If you have tubeless, you go faster and look better in your skin suit. Apparently you become more attractive to supr hot triathlon babes too.

    The answer to power is social media x followers x mental illness all over moral compass.

    Or 12 watts or yes. Depending
  • mariamartinez
    mariamartinez Posts: 94
    Like this one? this is much simplified with usual caveats (weight / CRR / air pressure / CDA all assumed)

    https://drive.google.com/open?id=1VSfcK ... lNDHrGr2Qk

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