Longer stem or laid back seat post?

coinneach
coinneach Posts: 79
edited March 2015 in Road general
I am contemplating one or the other, and welcome comments.
I don't want to spend £100 on a bike fit.
One option would take me slightly further forward on the bike: is the angle of shin when pedal fully forward the main determining factor?
Thanks
"It is good to have an end to journey toward, but it is the journey that matters in the end."

Comments

  • imposter2.0
    imposter2.0 Posts: 12,028
    Not enough information for anyone to make a decision for you one way or the other. Both will change your position, but nobody knows if your position is correct or not in the first place.
  • ForumNewbie
    ForumNewbie Posts: 1,664
    Try both and see which feels more comfortable on a ride.
  • trailflow
    trailflow Posts: 1,311
    How does your bike feel when you are riding standing up ? if it feels small then go for a longer stem.
  • debeli
    debeli Posts: 583
    Are you still growing? If your set-up was right last year and the year before, what has changed?

    What are you looking to gain? Is it a comfort thing or are you compensating for an injury or just experimenting?

    To each their own, but for me the fore-aft position of a saddle is the second thing I 'set' after seat height.

    Once that is right, the height of the bars and (these days) the length of the stem follow.

    With seat fora-aft settings, I look for the forward kneecap to be directly above the fulcrum of the pedal with the cranks horizontal.

    After that, I want the handlebar to obscure the front hub when my hands are on the hoods. There are so many variables that this question cannot adequately be answered on a forum.

    Most (all) of what I garnered over the years about set-up, geometry and position was from more-experienced cyclists in clubs or among pals who rode. If you can swallow your price, an excellent route to good set-up is to go for a ride with someone experienced who, you trust. They will see what you cannot.

    Beware of fashion and trend. If it's speed you want, watch footage of the pro-peloton. Lots of clues there, not least that nobody has the same idea about set-up, even at that level.

    Are your two proposed option really your only options?

    Have fun solving it and enjoy your riding, but not today.... it is raining and horrid.
  • tomisitt
    tomisitt Posts: 257
    Buy a copy of Bike Fit by Phil Burt, £15 from Amazon.
  • rafletcher
    rafletcher Posts: 1,235
    coinneach wrote:
    I am contemplating one or the other, and welcome comments.
    I don't want to spend £100 on a bike fit.
    One option would take me slightly further forward on the bike: is the angle of shin when pedal fully forward the main determining factor?
    Thanks

    For saddle fore/aft position, one guide is to get the front of the kneecap (get a helper to use a plumb line) over the centre of the pedal spindle when the cranks are horizontal.
  • Both will have different effects. What do you want to change about your position/fit?
  • darkhairedlord
    darkhairedlord Posts: 7,180
    feet first, then position your saddle to provide correct leg alignment, angles etc. then position your bars for your desired fit. Bar position should always be last and is determined by the others, in that order.
  • 86inch
    86inch Posts: 161
    tomisitt wrote:
    Buy a copy of Bike Fit by Phil Burt, £15 from Amazon.

    +1 from me, i got a copy for £4.49 on my Nook e-reader. Had a knee problem and i bought this to check things out. As it turned out i've no fit problems, but the section on injury and recommended exercises sorted my ITB issues so it was a bargain!
  • styxd
    styxd Posts: 3,234
    coinneach wrote:
    is the angle of shin when pedal fully forward the main determining factor?
    Thanks

    No, this shouldn't play a part in fitting a bike.

    It all comes down to balance; too much weight on your hands? Then a layback post might help. Not enough weight on your hands? It's likely you need to fit a longer stem and move your saddle forward.
  • coinneach
    coinneach Posts: 79
    Thanks for all the advice, guys (even when it's contradictory!)
    FYI I'm going with a compromise of slight laid back for comfort, and 1cm longer stem.
    "It is good to have an end to journey toward, but it is the journey that matters in the end."
  • tomisitt
    tomisitt Posts: 257
    You really shouldn't adjust your saddle position simply to extend your reach. This will reduce your power output and can lead to injuries. Leave your saddle where it is (assuming it's in the right place) and extend your reach with a longer stem. Better to have a 130mm stem than put your saddle too far back.
  • iron-clover
    iron-clover Posts: 737
    I would agree with those saying to sort the saddle before the handlebars. I have also been told that the knee should be directly over the pedal when at 90 degrees as this is the point where the most force is being transmitted and this will mean it is transmitted as efficiently as possible (and hopefully put least strain on the knees).

    However, if you drastically change your handlebar position, you will also have to re-adjust the saddle. For example the difference between a road bike and a TT bike, the TT bars are typically lower and further forward- and the saddle will probably need to be raised and pushed forward a little to keep the angles etc the same- think of it as rotating the whole position around the bottom bracket.
    I found I needed to do this slightly when I lengthened the stem and dropped the handlebars on my road bike too, but in each case the saddle movements are small I basically had to sit on the turbo and make small adjustments until it felt 'right', and then also making adjustments if needed on a test ride as well.

    Good luck!