Hills - the ruse?

Discussion in 'Cycling Training' started by james.dippel, Jun 20, 2003.

  1. i2ambler

    i2ambler New Member

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    I dont think I have a wide enough range for these hills.. I also noted later that my freaking rear brake was rubbing ever so slightly. I bought a 2002 bike from a guy who did all crits, and its geared for all flats. How do I find out what Im running in the back? Its a dura-ace cassette.. He said he 'swapped it out' because he never rode hills. I, however, want to increase fitness by riding some hills.
     


  2. TheDude

    TheDude New Member

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    If he did crits, then he's probably got something like an 11-21. That means 11 teeth on the small ring and 21 on the large. If the cassette is clean, you can read the markings on the side to see how many teeth. Otherwise, you'll have to count them. You might want to get a cassette with a 12-25 range, or even bigger if necessary.

    BTW, if you're new to cycling, cassettes and chains wear out, and they wear together. Here's a good discussion on chain wear link
     
  3. i2ambler

    i2ambler New Member

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    ahh I looked for markings, but didnt see any. I dont want to take apart the cassette to see them. I will count and find out. if its 21, then I surely need something like a 25.

    WIll there be a /great/ difference between the 21 and 25?
     
  4. TheDude

    TheDude New Member

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    Absolutely. Cycling and gears is all about what's called 'gear-inches'. Basically, it's the number of inches your bike will go forward for one pedal stroke in any given gear combination. The longer the distance, the harder it is to push the pedals; the shorter the distance the easier to push the pedals.

    Go to this page and enter your gear information for both the front and back. You'll also need to measure your wheel diameter. After doing so, you'll get a nice little custom report explaining just what the difference is between gears. Print one for your bike setup, and then change the cassette numbers to something you might like to try. You'll then be able to compare the two.

    If you're not sure what 'standard' cassette offerings are available, you can go to www.coloradocyclist.com and look up Durace cassettes and check out the different sizes.
     
  5. VeloFlash

    VeloFlash New Member

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    The instrument is known as an inclinometer but it only measures angles in degrees. It is also used to assist in installing satellite dishes.

    To obtain a % gradient you would need to know the base distance on the horizontal, elevation at starting point and elevation at finishing point.

    The problem with calculating the base or horizontal is that roads up high hills/mountains meander so a direct horizontal from A to B would result in a steeper gradient than actual.

    I would consider surveyors would use GPS equipment to measure horizontal distance and height over each straight section of the climb and aggregate the distances to calculate an average gradient.

    J-Mat - I was only pulling your chain! :)
     
  6. TheDude

    TheDude New Member

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    Unless I'm missing something, can't you just convert radians to % grade? It will, of course, only be the angle/grade at any given point.
     
  7. VeloFlash

    VeloFlash New Member

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    Of course. There are angle tools around that will provide this information to calculate percentage gradients. But remember that unless a detailed profile of the hill/mountain is displayed showing percentage grades over sections, the majority of gradient information relates to an average percentage of the total climb.
     
  8. i2ambler

    i2ambler New Member

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    We can, instead of using scientific rhetoric, just use this measuring device!!

    Easiest
    Easy
    heartrates a risin'
    hmm legs feeling hot
    ouch, legs REALLY burning now!
    Whoa, heart exploding
    'Dead'
     
  9. Spider1977

    Spider1977 New Member

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    No the instrument is called a Clinometer, they are made by Suunto and they have a degree and percentage scale. Ask any forester because they use them to measure the height of trees as well as the grade of slopes.
     
  10. VeloFlash

    VeloFlash New Member

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    Actually, we are both right. My source is from surveyors who call them inclinometers as is also the instrument on dash boards in four wheel drives. The dictionary defines both.

    http://www.geodetic.com.au/category497_1.htm
     
  11. neilcooper

    neilcooper New Member

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    Actually, I think you might be the one needing the schooling. :)

    45º is NOT 26.5% gradient. 45º is actually 100% gradient.

    Maybe you meant the other way around?

    Think of it this way, the percent grade is the rise as a percentage of the level distance.

    Lets say you are about to travel up a hill from sea level. The summit of the hill is 50m above sea level. Lets also assume you are traveling in an easterly direction (you'll see why in a moment).

    Assume you have GPS that is perfectly accurate (not invented yet) and at the summit it tells you that you've moved 50m east. You've moved the same amount vertically as you did horizontally. The horizontal distance was 100% of the vertical distance. 100% grade. If you draw 2 lines on a piece of paper that are the same length, one horizontal & one vertical and then draw a third line to join them up (forming a triangle) the angle from the horizontal to the line you drew last is 45º. Therefore a 100% grade is 45º.

    The sharpest hill you can have expressed in terms of degrees (angle) is 90º. Not really a hill actually, more like a vertical cliff face.

    However if grade is expressed in terms of percentage it can be a lot more than 100%.
     
  12. Spider1977

    Spider1977 New Member

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    Veloflash as I'm a professional forester who uses one of these instruments nearly every day I do know what I'm talking about!

    The CLINOMETER does not need knowledge of any distances to measure slope - you simply look through the instrument up the slope. Also it has a degrees and percentage slope scale on it. The most common ones are made by Suunto, you can go to their web site and have a look.

    If you want to measure the height of something (in my case a tree), then of course you need to know the distance from the base of the tree. Then, through trigonometry you can calculate the height.

    I suggest you stick to riding your bike! ;)
     
  13. VeloFlash

    VeloFlash New Member

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    I have been riding my bike in the nearly four years it took you to reply the second time! :)
     
  14. neilcooper

    neilcooper New Member

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    Long enough to now understand the difference between degrees & percentage gradient? ;)
     
  15. Sillyoldtwit

    Sillyoldtwit New Member

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    I do enjoy a good fight, especially when I'm at the ringside like this. Tyson

    [​IMG]
     
  16. neilcooper

    neilcooper New Member

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    Not much of a fight goin' really. More like 'The Sounds of Silence".

    Silence frequently occurs when someone's ego is just a tad bigger than their capacity to realise or acknowledge they don't know everything, or have made a mistake or ....
     
  17. neilcooper

    neilcooper New Member

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    Come back Velo, it was all in good fun. :)
     
  18. frenchyge

    frenchyge New Member

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    ....or when it's been 4.5 years since the conversation has had any relevance and one party has decided to just let it go....

    (echoes) ...let it go...

    (echoes) ...let it go...

    (echoes) ...let it go. :rolleyes:
     
  19. neilcooper

    neilcooper New Member

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    Firstly, I had clicked on his profile and noticed that he hadn't posted at this forum since 24th of May which was only a day or two after my last comment to him. I just hated to think I may have been the reason he was staying away (or at least stopped posting). It was my peace offering.

    Secondly, in a thread on the subject of hills, the discussion of gradients will be relevant even ten years from now. If you think the thread should die, why bump it?
     
  20. mikesbytes

    mikesbytes New Member

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