I have tinkered excessively with my bike fit over the years. I recently saw the fit suggestion that there be a 90-degree angle from the torso to the arm (while on the hoods). Thing is, when I increase the reach to that point, my power output drops 20%+ for the same perceived effort -- which results in a 3 - 4 mph drop up a 12% grade. (The max I can go at full power puts me at about 75-80-degrees.) Yes, I know there's more to a proper fit than power, but if it drops that much, can that really be right? Is that a position that just takes time to adapt to? Or, is that just for a more aggressive/racing type fit? (I ride 6,000+ miles/yr., but don't race. And my house is 600+ feet up the side of a mountain.)

  • 1
    Are you optimising for power, duration, climbing speed, or comfort ?
    – Criggie
    Jan 22, 2017 at 5:08
  • Nobody else can tell you what you need. That comes from you.
    – andy256
    Jan 22, 2017 at 6:40
  • Yeah. Bike fit is a personal thing. Working on charts and angles and stuff can help to start, but at the end of the day, whatever works for you.
    – Batman
    Jan 23, 2017 at 4:07
  • 1
    Do you mean 90 degree torso to arm, or 90 degree upper arm to forearm? I see KevinC answered the 90 degree elbow bend, but your question appears to mention torso to arm...
    – Rory Alsop
    Jan 23, 2017 at 11:03
  • You don't need to worry about angles on a 12% climb! Just watch tv, if it's steep, someone would almost always stand up and attack
    – imel96
    Jan 25, 2017 at 22:22

2 Answers 2


That 90 degree suggestion is purely for getting an optimal fit for aerodynamics. By bending your arm to 90 degrees, you're not presenting any of your forearm to the wind. If you watch the pros ride, this is typically how they'll carry themselves on flats and descents. Ultimately, you need to be comfortable though, and if bending your arms that much causes you to lose that much power, then it's probably not the best position for you. It's possible that there are other modifications to your fit that could be done to correct this, but that would require experimentation and/or a professional fitting. Check out this video from BikeRadar. It addresses your question pretty well.

  • I like how you answered the question and only reference the video link as further information.
    – Criggie
    Jan 23, 2017 at 7:25

Firstly, I was talking about the torso to arm bend (at the shoulder, NOT the elbow). As a bit of an update, after sliding my saddle rearward, it seemed I could get the reach a couple cm longer before losing power. While riding -- crawling? -- uphill, however, it became apparent something wasn't right. After more tinkering, turns out moving the saddle forward 5 mm, and shortening the reach by 2 cm allows me to go up a 10%+ grade at least 3 mph faster! So, I'll stick with this, regardless of what all those bike fitters I've been to have told me (i.e., that I'm too scrunched up). I do know my torso is much shorter than normal, compared to my legs, guess that's part of it. Perhaps being "upright" (walking/standing) all day at work doesn't help, either.

  • I am not sure this is an answer to your own question of , "Do I really need a 90 degree arm/torso angle?" by just saying, "I think I'll stick with this" But, did you test this theory over many dozens of tests? I sometimes go up hills 3mph faster from just eating better and being better hydrated. Feb 9, 2017 at 22:47

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