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  #1  
Old 07-24-2017, 03:13 PM
gregblow gregblow is online now
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inseam measurment protocol

I have been struggling with saddle height over the years. Can anyone help me with the correct way to measure cycling inseam? I have read all the stuff out there. I am primarily confused on how hard to pull it up the level in your crouch.

If i pull up on the level to the amount of pressure felt when sitting on the saddle, I get 83 cm. When i set my saddle at 73cm. i just cant ride there comfortably. The lower I get, the better it feels. I have landed at 70cm. This puts my saddle really low on my 56 frame. I am 175cm tall.

Am i measuring it wrong? Maybe I have a long torso and short legs. So confused.
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  #2  
Old 07-24-2017, 04:51 PM
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73Bronco 73Bronco is offline
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I can't answer your question but do offer up two trains of thought

If you're comfortable, does it matter?

Maybe time to get a fitting?

Sent from my SAMSUNG-SM-G891A using Tapatalk
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  #3  
Old 07-24-2017, 05:05 PM
Peter P. Peter P. is offline
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All your numbers check out with me.

Your frame size is good for your height.

Your inseam would indicate a 56cm frame.

Sure; your saddle height is somewhat low relative to the formulas, but a host of things could explain it.

Yeah; I can understand how a 70cm saddle height would look low on a 56cm frame (but I don't think it would be too far off), or it might appear the bars are too high relative to the saddle height or headtube size. You could downsize your frame to a 54cm and use a longer stem, or install a 73 degree stem on your current bike.
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  #4  
Old 07-24-2017, 07:09 PM
gregblow gregblow is online now
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Thanks. Maybe I get too caught up in formulas. I have been fit maybe 6-7 times. Each time it has produced different numbers. At this point I have a hard time trusting in a fitter.
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  #5  
Old 07-24-2017, 07:23 PM
Peter P. Peter P. is offline
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Quote:
Originally Posted by gregblow View Post
Thanks. At this point I have a hard time trusting in a fitter.
That's because YOU are your best fitter.

After having all those fit sessions, you start to see trends; upper and lower limits, and methodologies and their similarities and differences. Think of it as paying for an education in bike fit.
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  #6  
Old 07-25-2017, 03:51 AM
macaroon macaroon is offline
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You've probably got a leg length discrepancy; go and see a good physio. It's difficult to sit comfortably when one leg is shorter than the other!
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  #7  
Old 07-25-2017, 11:44 AM
11.4 11.4 is offline
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Inseam measurements aren't really the way to fit yourself properly. Different people will settle onto a bike saddle differently in ways that have no relation to where that level might fit. Further, you tend to rotate your hips back and forth a bit as you put out different levels of exertion, which also changes effective bike fit. And so on. Fit yourself by how you actually sit on the bike, not by a calculation that won't be as accurate.
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  #8  
Old 07-25-2017, 12:46 PM
gregblow gregblow is online now
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Quote:
Originally Posted by 11.4 View Post
Inseam measurements aren't really the way to fit yourself properly. Different people will settle onto a bike saddle differently in ways that have no relation to where that level might fit. Further, you tend to rotate your hips back and forth a bit as you put out different levels of exertion, which also changes effective bike fit. And so on. Fit yourself by how you actually sit on the bike, not by a calculation that won't be as accurate.
Thanks for your recommendation. I appreciate your insight.
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  #9  
Old 07-25-2017, 10:40 PM
John H. John H. is online now
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73cm

73cm does sound high for an inseam measurement of 83cm.

My inseam is 85cm and my saddle height is 73.2cm.
And I have size 44.5 feet.

My guess is that you should be closer to 70-71cm.

A 56cm flat toptube frame would be tall for a 70-71cm saddle height.
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  #10  
Old 07-25-2017, 10:43 PM
John H. John H. is online now
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Lemond

If you are looking at the old Lemond formula, keep in mind that that formula was just a general rule and it was based on using shoes and pedals with much more stack than most of us use today.

Maybe 2cm diff-
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  #11  
Old 07-26-2017, 02:56 AM
rustychisel rustychisel is offline
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I have used the Guimand/Hinault/Lemond method and it's an ok starting place.... stand with stocking feet and get that tape measure right up there, until you feel the pubic bone. Multiply measurement by 1.09.

Set bike up straight, with cranks parallel to seattube and measure from centre of pedal spindle to flat top of saddle.

Adjust for you.
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  #12  
Old 07-26-2017, 02:57 AM
rustychisel rustychisel is offline
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Quote:
Originally Posted by John H. View Post
If you are looking at the old Lemond formula, keep in mind that that formula was just a general rule and it was based on using shoes and pedals with much more stack than most of us use today.

Maybe 2cm diff-
can be true dat.
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  #13  
Old 07-26-2017, 10:36 AM
John H. John H. is online now
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11.4

11.4 is right.

Two people could have exact same inseam measurements and wildly different saddle heights.
Has to do with every joint, flexibility, foot length, cleat position, saddle, saddle setback...
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  #14  
Old 07-27-2017, 04:13 PM
gregblow gregblow is online now
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Thanks everyone! I am at 72cm now.
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