Average Male Inseam to Height Ratio?
11-06-21, 08:23 AM
#51
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Seems pointless, unless you also layer in metrics such as average arm length, average neck and head height (or alternatively average torso length) etc.
11-09-21, 05:43 PM
#52
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Don't know if you have a background in statistics or not. Bottom line is inseam length (independent of height) still dominates for the vast bell curve of cyclists out there. There is a correlation however. Dave Moulton's chart is derived by thousands of fittings and he is a pre-eminent expert on the subject. So is Sheldon Brown. Both subscribe to the 2/3 X's cycling inseam for frame size. I do too. Statistically most (not all) derive their height in their legs. Tall people many times have pedestrian length torsos. This applies to Sheldon Brown and myself and countless others. As a result, bicycles are designed to grow vertically almost 2:1 versus horizontally in frame size. This is not happenstance but based statistically on a normal distribution of height to inseam ratio. The reason that seat tube length or now virtual seat tube length with the advent of sloped top tube geometry bikes predominates is because virtual or actual seat post length dictates head tube length. In the grand scheme it is the ratio of seat post to head tube length that matter for saddle to handlebar drop. The other prevailing factor is top tube length and again, top tube does not increase nearly as must as seat post and head tube length between frame sizes which agrees with the statistical norm that torso size does not change nearly as much as inseam for different size people.
HTH,
George
HTH,
George
11-10-21, 05:09 PM
#53
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11-10-21, 09:07 PM
#54
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"Men will typically have an inseam 46-47% of their height and although it may not sound like a big difference, less than 45% or more than 48% is noticeable short or long legged respectively. Contrary to some popular opinion, women do not have longer inseams as the ratio is very similar. Women's legs appear longer as their waists are higher."
Copied from the website below.
https://bikedynamics.co.uk/bikesizingbd.htm
Copied from the website below.
https://bikedynamics.co.uk/bikesizingbd.htm
11-11-21, 03:36 PM
#56
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Does anyone know how much this ratio has changed since 2007?
My ratio is 0.43.
My ratio is 0.43.
11-11-21, 04:40 PM
#57
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Well, obviously in the far past the ratios were much lower, but not sure 2007 was back far enough
11-11-21, 05:50 PM
#58
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"Men will typically have an inseam 46-47% of their height and although it may not sound like a big difference, less than 45% or more than 48% is noticeable short or long legged respectively. Contrary to some popular opinion, women do not have longer inseams as the ratio is very similar. Women's legs appear longer as their waists are higher."
Copied from the website below.
https://bikedynamics.co.uk/bikesizingbd.htm
Copied from the website below.
https://bikedynamics.co.uk/bikesizingbd.htm
Otto
11-11-21, 06:05 PM
#59
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[QUOTE=Blopslee;4073286]
I remember tearing my hair out at the wrong turn the industry took with sizing compact frames...
In my view, the obvious way forward was either to switch to effective top tube length, which together with head tube length, is all you really need to know, or to continue with seat tube size, but make it where the effective top tube hits the seatpost, so it continued to mean the same thing. Who gives a stuff about standover clearance anyway?
Originally Posted by MIN
Interesting insight from that link:
The way I determine frame size is to start by saying this equals two-thirds of the rider’s inseam.
I think things were thought to be a little more clear before sloping top tubes.
The way I determine frame size is to start by saying this equals two-thirds of the rider’s inseam.
I think things were thought to be a little more clear before sloping top tubes.
I remember tearing my hair out at the wrong turn the industry took with sizing compact frames...
In my view, the obvious way forward was either to switch to effective top tube length, which together with head tube length, is all you really need to know, or to continue with seat tube size, but make it where the effective top tube hits the seatpost, so it continued to mean the same thing. Who gives a stuff about standover clearance anyway?
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Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
11-11-21, 06:26 PM
#60
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"Men will typically have an inseam 46-47% of their height and although it may not sound like a big difference, less than 45% or more than 48% is noticeable short or long legged respectively. Contrary to some popular opinion, women do not have longer inseams as the ratio is very similar. Women's legs appear longer as their waists are higher."
Copied from the website below.
https://bikedynamics.co.uk/bikesizingbd.htm
Copied from the website below.
https://bikedynamics.co.uk/bikesizingbd.htm
It is also very interesting what he says about inseam vs saddle height. He noted that pelvis depth varies widely between individuals and has no correlation to their height. Using his client fit database he came up with a revised formula for predicting saddle height based on both inseam and hip joint height. Full explanation on the link below:-
https://bikedynamics.co.uk/saddleheightformulae.htm
11-14-21, 10:26 AM
#61
Senior Member
Who gives a stuff about standover clearance anyway?
...effective top tube length, which together with head tube length, is all you really need to know
