Will shorter stem affect handling?

Father Faff
Father Faff Posts: 1,176
edited December 2013 in Road buying advice
A bike I have been demoing has a long 120mm stem as standard which is too long for me. With a 100mm stem (same as my current bike) it fits me good and seems to handle fine although I felt I got a bit more road buzz transmitted. Should I have any worries about swapping to a shorter stem? And why would a manufacturer fit such a long stem in the first place (Colnago CX Zero)?
Commencal Meta 5.5.1
Scott CR1

Comments

  • maddog 2
    maddog 2 Posts: 8,114
    it'll be fine. Don't be afraid to adjust the bike to fit you. Stem can gt longer/shorter, higher/lower. Put the bars where you feel comfortable. Different body shapes, flexibility, type of riding/racing can all change the sweet spot.
    Facts are meaningless, you can use facts to prove anything that's remotely true! - Homer
  • kajjal
    kajjal Posts: 3,380
    Changing stems to fit is normal as people have different preferences and riding positions. As long as it feels fine to you just enjoy the riding.
  • Tom Dean
    Tom Dean Posts: 1,723
    yes
  • rafletcher
    rafletcher Posts: 1,235
    It will make a difference of course - but whether it's that noticeable to you is quite another thing! It will "slow" the steering marginally. As to why it's 120mm in the first place - who knows. I'm no different a size/proportion now than I was 30 years ago (well my waist is bigger...). Back then I road a 60cm frame with 120mm stem, but only had 150mm of seatpost showing. Now I'm most likely on a 56cm frame with a sloping top tube, with a 100mm stem (cos I'm less flexible) and 300mm of seatpost showing. Fashions change as does flexibility.
  • pianoman
    pianoman Posts: 706
    I always wondered the opposite; if Specialized want everyone to squeeze onto the smallest frame possible with "a long stem" then why put a 100mm stem on a 56cm Tarmac in the first place? Surely that doesn't help people who buy from less knowledgable stores who think that they've got the right size. However, in some cases that can work the other way; on another brand I tested recently I felt pretty happy on the 56 with a stock stem of 105mm but was advised that a 54 would be better "because you can always use a longer stem". As soon as I had it set up with a reasonable amount of spacers (as in not all of the original ones left in, some above some below) the bike was unrideable - my elbows were being hit by my knees on nearly every pedal stroke and my back was on the point of giving out, plus we'd have needed at least a 120mm stem. Which means that the 56cm will be my choice (I'm 1.79 with an arm span of 1.84 and only an 82cm inside leg so a rather awkward shape to begin with - lots of torso and arms but short legs).

    So go for the 100 and as long as you don't find yourself binning the bike on every tight corner because the handling has changed so badly, then accept it for what it is and be happy :D
  • rick_chasey
    rick_chasey Posts: 74,639
    Will be fine.

    You'll barely notice it.
  • I recently changed mine from a 110 to a 100 and did not notice any changes in handling characteristics. It just felt more comfortable when on the hoods and in the drops.
  • on-yer-bike
    on-yer-bike Posts: 2,974
    I ride an old geometry 56 Cervelo, had a bike fit and was advised to go to 100 from 110. Didnt notice any difference with the steering and its a great handling bike. If Id had a 54 I would have needed loads of spacers under the stem as my legs are long, my saddle is high and Im not that flexible. Ideally I would have a frame with a shorter top tube for the frame size. You may want to consider doing the same.
    Pegoretti
    Colnago
    Cervelo
    Campagnolo
  • springtide9
    springtide9 Posts: 1,731
    I swapped from a 110mm to a 90mm no problem. It did make the bike more twitchy, but got used to it quickly/easily.

    I've switched stems from 130mm to 100mm in the past with no problems.. seems going below 100mm makes the difference.

    I think sub 90mm you'll just to be a bit careful regarding handling.. but seen/read posts people running 70mm stems no problems.
    Simon
  • andrew_s
    andrew_s Posts: 2,511
    No.
    Handling is determined by frame geometry - head tube angle, fork rake, and wheelbase, none of which change with a new stem.

    The steering input required changes from a pure forwards/backwards motion of each hand with a zero length stem, to more of a left/right movement as the stem gets longer. This means that you may notice the change at first, but you will adjust to it within a few rides.

    I've even heard of people adjusting to reversed stems (i.e. minus 60mm) with no problem.
  • maddog 2
    maddog 2 Posts: 8,114
    handling isn't just frame geo. It's weight distribution too, and stem length does influence this.

    As said, most lengths are fine but <80mm it starts to get a tad twitchy.
    Facts are meaningless, you can use facts to prove anything that's remotely true! - Homer
  • diamonddog
    diamonddog Posts: 3,426
    maddog 2 wrote:
    handling isn't just frame geo. It's weight distribution too, and stem length does influence this.

    As said, most lengths are fine but <80mm it starts to get a tad twitchy.
    ^^This