1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

The correct height of a saddle?

Discussion in 'Bicycle Mechanics and Repairs' started by summerdays, 24 Apr 2008.

  1. summerdays

    summerdays Cycling in the sun Staff Member

    Location:
    Bristol
    I was happy with my saddle position on my old bike, but I haven't got there yet with the new bike (he's called Fergus if that helps:biggrin:). They aren't directly comparable as the old one was a 17" frame with suspension seat post and "comfort saddle", whereas now its a 19" with no suspension.

    I feel quite comfortable cycling my husbands bike even though I can't touch the ground - and I am still moving this saddle upwards. Are you meant to be able to just touch the ground when sitting in the saddle? I read something somewhere that I can't place my finger on that suggested that you shouldn't start sitting in the saddle and that therefore the saddle could be slightly higher? (Or was that completely rubbish?)

    Does crank length make any difference to saddle height/comfort position?
     
  2. Tim Bennet.

    Tim Bennet. Entirely Average Member

    Location:
    S of Kendal
    Your saddle height does not really have any direct correlation with the ground. It's only relationship is with the pedals, so crank length is a factor.

    The classic way to find the saddle height (and this is easiest on a turbo or with help) is to sit on the bike normally with your heels on the pedals and turn the cranks (backwards if necessary).

    The saddle should be high enough that your heel only just reaches the pedal on the bottom of the stroke WITHOUT your hips rocking up and down to help lengthen your leg.
     
  3. simonali

    simonali Über Member

    Location:
    Wiltshire
    If the cranks on both bikes are the same length (it should be on the inner face of the crank somewhere) then just measure from the centre of the BB to the top of the saddle on the old one and transfer this to the new one. If the cranks are longer e.g. 170 on old bike and 175 on the new one, just take off 5mm.
     
  4. doyler78

    doyler78 Well-Known Member

    Location:
    Co Down, Ireland
    When you are in your normal riding position on the bike and your foot is at the bottom of your pedal stroke then your knee angle should be around 25 degrees. You will need a goniometer to measure this however it is thought to be the method which works best for most people just not very practical.
     
  5. If your knees don't hurt after a looong ride it's probably ok. But there should be a bit of a bend in your legs at the point of the longest stroke (as dom says).
     
  6. OP
    OP
    summerdays

    summerdays Cycling in the sun Staff Member

    Location:
    Bristol
    The cranks are different on the two bikes - 170 and 175 - just been and had a look. I will have to wait until hubby is around to measure the distance to the saddle (as the old one is suspension seat post I will need to be sitting on it to get the distance I guess).

    How will having longer cranks effect how it feels to cycle?
     
  7. Tim Bennet.

    Tim Bennet. Entirely Average Member

    Location:
    S of Kendal
    There are a few 'experts' around who believe that crank length is critical, and you can find on the internet someone who has made a career out of catering for these people with custom built cranks up to about a yard long.

    For everyone else, (apart from the very short / children) varying between 170 and 175mm does even seem to be noticeable. I have a mixture on different bikes.
     
  8. Gerry Attrick

    Gerry Attrick Lincolnshire Mountain Rescue Consultant

    No goniometer needed. I used this method by joining two straight pieces of timber at 25 degrees using an engineer's adjustable square, or you could use a protractor. I find it an excellent way of finding saddle height.
     
  9. doyler78

    doyler78 Well-Known Member

    Location:
    Co Down, Ireland
    Yeah I can see that would work. I bought myself one. Cost me £10 including postage from a online physio shop - can't remember the name now. I was starting to get pain in the back of my knee and found by using this method that my knee was sorted so I agree that it is an excellent method that works for me too.
     
  10. OP
    OP
    summerdays

    summerdays Cycling in the sun Staff Member

    Location:
    Bristol
    Could I take a photo of myself (well get someone else to take it), and then measure the angle on the computer?

    I did 15 miles today and its definately still too low - I don't feel that my leg is extending enough, and I want to use my arch of my foot rather than using the front part of my foot.
     
  11. HJ

    HJ Cycling in Scotland

    Location:
    Auld Reekie
  12. Chris James

    Chris James Über Member

    Location:
    Huddersfield
    Just go for the heel on the pedal method. It'll be somewhere near. I did that and was very happy with it on my new bike.

    Then I decided I should be more scientific and measured my inside leg and used the Greg LeMond 109% to calculate my optimum height.

    Which happened to be exactly the same as the heelm on pedla method had given.

    Oh and I agree with Tim about crank length too. I have ridden bikes with 165mm cranks and 175mm and can't tell the difference.