Go Back  Bike Forums > Bike Forums > Fitting Your Bike
Reload this Page >

Stem Length & Fit According to your Proportions

Notices
Fitting Your Bike Are you confused about how you should fit a bike to your particular body dimensions? Have you been reading, found the terms Merxx or French Fit, and don’t know what you need? Every style of riding is different- in how you fit the bike to you, and the sizing of the bike itself. It’s more than just measuring your height, reach and inseam. With the help of Bike Fitting, you’ll be able to find the right fit for your frame size, style of riding, and your particular dimensions. Here ya’ go…..the location for everything fit related.

Stem Length & Fit According to your Proportions

Old 01-25-21, 02:17 PM
  #1  
Moisture
Drip, Drip.
Thread Starter
 
Moisture's Avatar
 
Join Date: Oct 2020
Posts: 1,017
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 680 Post(s)
Liked 110 Times in 92 Posts
Stem Length & Fit According to your Proportions

There seems to be some misconception with what sort of stems work best according to your proportions.

Most bike manufacturers spec a specific type of stem length, usually on the longer side, more or less across the board. However they think you should fit on the bike I am sure is most often a case by case condition depending on rider proportions.

I am basing which length stem I require based achieving the right balance between leaning and an upright riding position, with the seat set backwards as far as reasonably possible for better fit and balance

I understand that people with longer torsos, particularly those of you who are more on the slender side will require a longer stem and maybe even drop bars, in more extreme circumstances.

Lets say that a 25-32mm, stem is the shortest you can go based on handlebar clamp diameter.

So 25-120mm length stems are the most common range, with either of those numbers being toward an extreme side for fit circumstances. So anything in between, namely 40-90mm is likely a releastic range for the majority of bikers.

Point is, by sliding your seat further back and trying out different length stems, again, provided that your frame is a suitable fit for you, this is certainly an experiment which can be very helpful with achieved a better fit.
Moisture is offline  
Old 01-25-21, 02:32 PM
  #2  
mack_turtle
n00b
 
Join Date: Jan 2008
Location: Austin, TX
Posts: 1,397

Bikes: Surly Karate Monkey, Twin Six Standard Rando

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 425 Post(s)
Liked 456 Times in 272 Posts
Originally Posted by Moisture View Post
Point is, by sliding your seat further back and trying out different length stems, again, provided that your frame is a suitable fit for you, this is certainly an experiment which can be very helpful with achieved a better fit.
I'm not going to mince words here. this is utter bollocks, you don't know what you're talking about, you should not be trying to pass off your ignorance as good advice, and your confidence on these topics is a textbook example of the Dunning-Kruger Effect. your advice is based on zero experience in the real world, and professional bike fitters would never agree to your methods because they have fitted hundreds of individuals, including professional athletes, on bikes using very different methods that directly contradict your assumptions.

Last edited by mack_turtle; 01-25-21 at 04:03 PM.
mack_turtle is offline  
Likes For mack_turtle:
Old 01-26-21, 05:51 AM
  #3  
cubewheels
Senior Member
 
Join Date: Jun 2020
Location: Manila, Philippines
Posts: 1,784

Bikes: A really old BMX bike, Phantom 20 kid's MTB, Jackal Mio Gravel Bike

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 763 Post(s)
Liked 363 Times in 292 Posts
Originally Posted by Moisture View Post
with the seat set backwards as far as reasonably possible for better fit and balance
Definitely a wrong assumption when setting fore and aft seat position (setback).

There's KOPS, COGS, laidback/cruiser, and TT. Those are purely a matter of choice and the nature the rider will use their bike for - leisure, commuting, recreation, race / race training, off-road, etc.
cubewheels is offline  
Likes For cubewheels:
Old 02-04-21, 11:52 AM
  #4  
tomato coupe
Senior Member
 
Join Date: Jul 2009
Posts: 2,063

Bikes: Colnago, Van Dessel, Factor, Cervelo, Ritchey

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 1249 Post(s)
Liked 1,813 Times in 745 Posts
There seems to be an endless parade of threads like this ...
tomato coupe is offline  
Likes For tomato coupe:
Old 02-04-21, 02:54 PM
  #5  
Eric F
Habitual User
 
Eric F's Avatar
 
Join Date: Jan 2020
Location: Altadena, CA
Posts: 1,043

Bikes: 2018 Storck Fascenario.3 Platinum, 2003 Time VX Special Pro, 1977 Nishiki ONP, 1999 Trek 9900 Team Issue

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 511 Post(s)
Liked 1,050 Times in 502 Posts
Originally Posted by Moisture View Post
There seems to be some misconception with what sort of stems work best according to your proportions.

Most bike manufacturers spec a specific type of stem length, usually on the longer side, more or less across the board. However they think you should fit on the bike I am sure is most often a case by case condition depending on rider proportions.

I am basing which length stem I require based achieving the right balance between leaning and an upright riding position, with the seat set backwards as far as reasonably possible for better fit and balance

I understand that people with longer torsos, particularly those of you who are more on the slender side will require a longer stem and maybe even drop bars, in more extreme circumstances.

Lets say that a 25-32mm, stem is the shortest you can go based on handlebar clamp diameter.

So 25-120mm length stems are the most common range, with either of those numbers being toward an extreme side for fit circumstances. So anything in between, namely 40-90mm is likely a releastic range for the majority of bikers.

Point is, by sliding your seat further back and trying out different length stems, again, provided that your frame is a suitable fit for you, this is certainly an experiment which can be very helpful with achieved a better fit.
Hmmm...It seems to me that, for over a century, people have been working on how humans can power a bicycle most efficiently. While I agree with your point that each rider should find a position that is most comfortable for their unique body, and some changes to parts may be required to do that, the current level sophistication of bicycle fitting technology really takes a lot of the guesswork out of it. The advice of just pushing your seat back, and experimenting with different stems is far too random and pretty ignorant.

Your advice also completely ignores the major factor that not everyone wants to ride the same way, and different fit types are better for different styles of riding. For example, my desire is to get down the road efficiently and quickly, so my fit is intended to not only to be biomechanically efficient for my pedaling action, but also minimize the forces I'm battling against - wind resistance, rolling resistance, and gravity. As such, based on the pics you have posted of you on your bike, our goals seem to be significantly different, and your advice is pretty irrelevant.
Eric F is offline  
Likes For Eric F:
Old 02-04-21, 08:52 PM
  #6  
Serenity Yee
Registered
 
Serenity Yee's Avatar
 
Join Date: Sep 2015
Posts: 72
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 15 Post(s)
Liked 8 Times in 7 Posts
Drippity drip knows everything.
Serenity Yee is offline  
Old 02-04-21, 10:22 PM
  #7  
Ferrouscious 
Some Weirdo
 
Ferrouscious's Avatar
 
Join Date: Dec 2017
Location: Rexburg, ID
Posts: 502

Bikes: '86 Maruishi Excellence, '86 Schwinn Prelude, '88 Cannondale SR2000, '74 C. Itoh "Racer"

Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 222 Post(s)
Liked 139 Times in 90 Posts
Why do I read these? I know I'm going to hate myself afterwards, but I still read on. smh
__________________
Somewhere, a village is missing its idiot.
Ferrouscious is offline  
Likes For Ferrouscious:
Old 02-05-21, 03:01 AM
  #8  
Branko D
Senior Member
 
Join Date: Feb 2018
Posts: 259
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 91 Post(s)
Liked 96 Times in 61 Posts
Here's a simple experiment to run. Set an alarm clock early in the morning this Sunday, make breakfast and coffee and go ride for, say, six hours. That's not an exceptionally long ride, but is long enough that your body will in no uncertain terms tell you how it feels about your bike fit and you won't be able to lie to yourself about it. Then you go to a bike shop and buy an entry level road bike which is in your size and have them fit you in a rudimentary fashion, practice riding it for a couple of weeks and then repeat the same ride.

Furthermore, the idea that everyone should be on some unorthodox fit specially tailored to their body is just nonsense. The human body is adaptable (and if yours isn't, quite likely exercise to adress that would help). The same person can learn to ride a recumbent (if they are so inclined), a MTB, a road bike and a TT bike, all of which have completely different fits when setup as intended for the sport they are for.

Last edited by Branko D; 02-05-21 at 04:30 AM.
Branko D is offline  
Likes For Branko D:
Old 02-05-21, 05:02 AM
  #9  
Moisture
Drip, Drip.
Thread Starter
 
Moisture's Avatar
 
Join Date: Oct 2020
Posts: 1,017
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 680 Post(s)
Liked 110 Times in 92 Posts
Setting the saddle all the way back may not make sense for everybody. But it would help you get lower, streamline yourself better, and improve power trasnfer provided you're using the correct stem length, right?

there's clearly something quite wrong with my proportions in present form to prefer such a short top tube, and a short stem on top of that. It feels fine when simply blasting down a straight road, but with my seat set so high due to my strap ins, it is extremely un aero.

, modern life is clearly about making sacrifices. I don't need to lean forward much to weigh the front axle. I don't need as much space to do so. This means that I have to be much more careful when transitioning weight to avoid upsetting balance.

This is clearly a problem which many of you do not have, or at least don't worry about. Maybe handling balance isn't top priority. I do totally agree that basing my ideas as being useful for many people for fit doesn't make any sense.

But adjusting saddle positioning and stem length- not necessarily backwards and shorter like I initially suggested - does make sense
.
Moisture is offline  
Old 02-05-21, 06:06 AM
  #10  
aniki
Senior Member
 
aniki's Avatar
 
Join Date: Mar 2017
Posts: 67
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Liked 58 Times in 31 Posts
Originally Posted by Moisture View Post
Setting the saddle all the way back may not make sense for everybody. But it would help you get lower, streamline yourself better, and improve power trasnfer provided you're using the correct stem length, right?
WRONG!! Again with the baseless nonsense. What saddle? How long are the rails? What setback on the seat-post? What is the seat tube angle? How high is the bottom bracket? What length are the crank arms? What size is the person riding the bike? What type of riding is the person doing? There are a million variations that could affect the optimum fore and aft position of a persons saddle! Again you're just making arbitrary statements based on absolutely no facts or experience whatsoever; please stop it.

Originally Posted by Moisture View Post
there's clearly something quite wrong with my proportions in present form to prefer such a short top tube, and a short stem on top of that. It feels fine when simply blasting down a straight road, but with my seat set so high due to my strap ins, it is extremely un aero.
There is absolutely nothing wrong with your proportions at all. Based on what you've said in previous threads, you have very low core strength and have tried to adapt a drop bar road racing bike into a sit-up-and-beg shopping bike and your subsequent position on the bike is a complete mess.

Originally Posted by Moisture View Post
modern life is clearly about making sacrifices. I don't need to lean forward much to weigh the front axle. I don't need as much space to do so. This means that I have to be much more careful when transitioning weight to avoid upsetting balance.
This is clearly a problem which many of you do not have, or at least don't worry about. Maybe handling balance isn't top priority.
I think you'll find that for anyone riding a road bike as it was intended, handling is very much a top priority! Most people don't have a problem with it unless their bikes are set up incorrectly.

Originally Posted by Moisture View Post
I do totally agree that basing my ideas as being useful for many people for fit doesn't make any sense.
The why do you insist on doing it?
aniki is offline  
Likes For aniki:
Old 02-05-21, 12:43 PM
  #11  
Branko D
Senior Member
 
Join Date: Feb 2018
Posts: 259
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 91 Post(s)
Liked 96 Times in 61 Posts
Think about it this way. Leg length is fixed, so if you push the saddle back and down to maintain the same distance to the pedals, you're effectively rotating the rider backwards in relation to the bottom bracket. You can rotate the rider around the BB pretty significantly - on a triathlon bike you're going to be rotated considerably forward compared to a road bike, while on a recumbent you are going to be rotated backward all the way, and people can produce power either way.
​​​​​However, consider what happens when you rotate the rider backwards a bit. To maintain the angle between the legs and the upper body (there's a limit how much you can bend over and still produce power, you can't just tell the rider to bend over more), you have to push the handlebars closer and up. You are not getting lower and more aero by pushing the rider back, on the contrary.

In any case, my advice is to get fitted on a road bike and do whatever it takes to ride it well without doing anything unorthodox with the fit. There's a learning curve and a period of adaptation, but stick with it and the end result will be so much better than if you try to reinvent bike fitting to account for your perceived unique physique.
​​​​​​
Branko D is offline  
Old 02-05-21, 12:59 PM
  #12  
Moisture
Drip, Drip.
Thread Starter
 
Moisture's Avatar
 
Join Date: Oct 2020
Posts: 1,017
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 680 Post(s)
Liked 110 Times in 92 Posts
The leaning forward position is very bad for your back. I've never heard of anyone getting optimal physical performance while training or riding with a rounded lumbar spine.
Moisture is offline  
Old 02-05-21, 01:13 PM
  #13  
Iride01
Hits [ENTER] b4 thinking
 
Iride01's Avatar
 
Join Date: Jul 2017
Location: Mississippi
Posts: 7,096

Bikes: '20 Tarmac Disc Comp '91 Schwinn Paramount '78 Raleigh Competition GS

Mentioned: 31 Post(s)
Tagged: 0 Thread(s)
Quoted: 2769 Post(s)
Liked 1,391 Times in 1,016 Posts
I've never heard of anyone getting optimal performance by staying as least aerodynamic as possible. At least not if optimal performance is on road bike doing a 130 mile ride in competition with others.
Iride01 is offline  
Old 02-05-21, 01:30 PM
  #14  
aniki
Senior Member
 
aniki's Avatar
 
Join Date: Mar 2017
Posts: 67
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Liked 58 Times in 31 Posts
Originally Posted by Moisture View Post
The leaning forward position is very bad for your back.
No it isn't. Stop stating your baseless opinions as fact.
Originally Posted by Moisture View Post
I've never heard of anyone getting optimal physical performance while training or riding with a rounded lumbar spine.
Which is why when cyclists achieve correct fit and positioning, they are able to rotate their pelvis instead of bending their lower spine. This is why millions of cyclists all over the world have been able to ride for hours on end in this position, pain and injury free for over 200 years!
aniki is offline  
Likes For aniki:
Old 02-05-21, 01:32 PM
  #15  
caloso
Senior Member
 
caloso's Avatar
 
Join Date: Jul 2002
Location: Sacramento, California, USA
Posts: 40,083

Bikes: Ridley Excalibur, Gazelle Champion Mondial, On-One Pompino, Specialized Rock Hopper

Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 2620 Post(s)
Liked 2,100 Times in 1,008 Posts
Originally Posted by Moisture View Post
The leaning forward position is very bad for your back. I've never heard of anyone getting optimal physical performance while training or riding with a rounded lumbar spine.
wut

caloso is offline  
Likes For caloso:
Old 02-05-21, 01:36 PM
  #16  
aniki
Senior Member
 
aniki's Avatar
 
Join Date: Mar 2017
Posts: 67
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Liked 58 Times in 31 Posts
This is Alf Engers; one of the fastest cyclists ever. He rode this position for almost 20 years....

aniki is offline  
Old 02-05-21, 01:37 PM
  #17  
Moisture
Drip, Drip.
Thread Starter
 
Moisture's Avatar
 
Join Date: Oct 2020
Posts: 1,017
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 680 Post(s)
Liked 110 Times in 92 Posts
Originally Posted by aniki View Post
No it isn't. Stop stating your baseless opinions as fact.

Which is why when cyclists achieve correct fit and positioning, they are able to rotate their pelvis instead of bending their lower spine. This is why millions of cyclists all over the world have been able to ride for hours on end in this position, pain and injury free for over 200 years!
So you really think that the guy in the below is riding with health lower back posture?

Originally Posted by caloso View Post
wut

^ whatever causes lower back rounding like this causes so many extra problems for your whole body, and performance included .
Moisture is offline  
Old 02-05-21, 01:41 PM
  #18  
mack_turtle
n00b
 
Join Date: Jan 2008
Location: Austin, TX
Posts: 1,397

Bikes: Surly Karate Monkey, Twin Six Standard Rando

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 425 Post(s)
Liked 456 Times in 272 Posts
Originally Posted by Moisture View Post
So you really think that the guy in the below is riding with health lower back posture?



^ whatever causes lower back rounding like this causes so many extra problems for your whole body, and performance included .
thanks, doc. where did you attend medical school, again?
mack_turtle is offline  
Likes For mack_turtle:
Old 02-05-21, 01:45 PM
  #19  
caloso
Senior Member
 
caloso's Avatar
 
Join Date: Jul 2002
Location: Sacramento, California, USA
Posts: 40,083

Bikes: Ridley Excalibur, Gazelle Champion Mondial, On-One Pompino, Specialized Rock Hopper

Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 2620 Post(s)
Liked 2,100 Times in 1,008 Posts
7 Rainbow jerseys. https://en.wikipedia.org/wiki/Tony_M...r_achievements
I'd say his performance has not suffered.
caloso is offline  
Likes For caloso:
Old 02-05-21, 01:48 PM
  #20  
mack_turtle
n00b
 
Join Date: Jan 2008
Location: Austin, TX
Posts: 1,397

Bikes: Surly Karate Monkey, Twin Six Standard Rando

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 425 Post(s)
Liked 456 Times in 272 Posts
look at this idiot! I'll bet he never won any races or anything with his back like that. what he needs is a flagpole of a stem so he can sit up like a windsail!
mack_turtle is offline  
Likes For mack_turtle:
Old 02-05-21, 01:50 PM
  #21  
caloso
Senior Member
 
caloso's Avatar
 
Join Date: Jul 2002
Location: Sacramento, California, USA
Posts: 40,083

Bikes: Ridley Excalibur, Gazelle Champion Mondial, On-One Pompino, Specialized Rock Hopper

Mentioned: 66 Post(s)
Tagged: 0 Thread(s)
Quoted: 2620 Post(s)
Liked 2,100 Times in 1,008 Posts
Originally Posted by mack_turtle View Post
look at this idiot! I'll bet he never won any races or anything with his back like that. what he needs is a flagpole of a stem so he can sit up like a windsail!
I've always said Eddy on the tops is more aero than most riders in the drops.
caloso is offline  
Likes For caloso:
Old 02-05-21, 01:52 PM
  #22  
badger1
Senior Member
 
badger1's Avatar
 
Join Date: Oct 2005
Location: Southwestern Ontario
Posts: 4,502
Mentioned: 21 Post(s)
Tagged: 0 Thread(s)
Quoted: 1203 Post(s)
Liked 423 Times in 239 Posts
Here's another fellow who has utterly ruined his health. Just think: if he had followed the fit recommendations popping up like noxious weeds on here lately, he might have done something in track racing/the Olympics. Sad.

badger1 is offline  
Likes For badger1:
Old 02-05-21, 01:56 PM
  #23  
mack_turtle
n00b
 
Join Date: Jan 2008
Location: Austin, TX
Posts: 1,397

Bikes: Surly Karate Monkey, Twin Six Standard Rando

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 425 Post(s)
Liked 456 Times in 272 Posts
I shared with Moisture a photo of my bike with a "rounded back" posture. I am not very flexible (I cannot bend at the waist and touch my toes to save my life) but I can ride comfortably for hours with my handlebar at least an inch below my saddle height. the bottom line is people with no experience riding, much less helping other people fit on their bikes, have NOTHING of value to add to this conversation. it's best that they sit back and learn instead of chiming in with advice that comes from ignorance.
mack_turtle is offline  
Likes For mack_turtle:
Old 02-05-21, 01:59 PM
  #24  
Moisture
Drip, Drip.
Thread Starter
 
Moisture's Avatar
 
Join Date: Oct 2020
Posts: 1,017
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 680 Post(s)
Liked 110 Times in 92 Posts
Sad to see you guys accepting the human body in a way its not designed to function.

Whats the excuse here? success over other people of similarly flawed proportions? How is this acceptable? This is not an accurate basis .

Its either you strive to do better or you accept the corruption of human life. Roll the dice
Moisture is offline  
Old 02-05-21, 02:00 PM
  #25  
mack_turtle
n00b
 
Join Date: Jan 2008
Location: Austin, TX
Posts: 1,397

Bikes: Surly Karate Monkey, Twin Six Standard Rando

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 425 Post(s)
Liked 456 Times in 272 Posts
someone needs to stop Julia before she hurts herself!
mack_turtle is offline  
Likes For mack_turtle:

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.