Stem lengths for a TCR - bike fit advice

Discuss light weight issues concerning road bikes & parts.
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Lewn777
Posts: 725
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

You attacked me I attacked back. You served, I vollyed.

I've read all the stuff on websites that you are quoting and I'm sure the OP has, the plumb-bob method and many of the 'bike fitting facts' you are quoting are very out of date. Most fitters disagree with each other, so there's no way there is one set of 'rules' to follow like some math equation.

Again you are wrong about the pros in road bikes, they ride smaller frames than they should and slam their seat back, run a 120mm or more stem that is slammed, open your eyes and look. I use the pro postition and I find it comfortable, so I suggest other people do too if they like it, but you need some core strength and flexibility. They do this for aero and sacrifice some power. A TT bike is totally different with different UCI demension rules and aero bars, totally not relevant to this OPs bike.

by Weenie


icantaffordcycling
Posts: 216
Joined: Wed Jan 09, 2019 5:03 am

by icantaffordcycling

Lewn777 wrote:
Fri May 17, 2019 6:01 am
many of the 'bike fitting facts' you are quoting are very out of date.there's no way there is one set of 'rules' to follow like some math equation.

Again you are wrong about the pros in road bikes, they ride smaller frames than they should and slam their seat back, run a 120mm or more stem that is slammed, open your eyes and look. I use the pro position and I find it comfortable, so I suggest other people do too if they like it, but you need some core strength and flexibility. They do this for aero and sacrifice some power. A TT bike is totally different with different UCI dimension rules and aero bars, totally not relevant to this OPs bike.
1. Read my post. I said the pump bob method provides a good ballpark estimate.
2. Read my post. I said the exact same thing about the pro cyclist's position. But pushing your saddle back you are changing the muscle groups being used (glutes vs quads). Changing muscle groups requires more time than a non-pro has.
3. Read your post. You brought up TT bikes first.

I think most of our arguments over the last two days have occurred because of you not being able to read through an entire post so I kept this one short.

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Lewn777
Posts: 725
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

icantaffordcycling wrote:
Fri May 17, 2019 5:56 am
Lewn777 wrote:
Fri May 17, 2019 5:20 am
Somewhere between 80-130mm stem hat the heck? That's like picking a random stem!
Pros often run their seats far back in the peloton because it's more aero, they also run far more forward for power as with TT bikes. It's a simple will known observation.
Please, by all means, write your opinion (not that there's any point because you can find it in 0.000004 seconds with a search engine). But please refrain from attacking other people's opinions, or we're going to be in flame wars until one of us gets banned.
1. My point was that adapting between a reasonably sized stem which I believe to be between 80-130 to facilitate a better bike fit is worth the small change in handling.
Wrong, the change in handling is massive, he should be deciding between 100-110-120 nothing outside that range. With this it really seems like you have no experience or clue what you're talking about.


2. Pros run their seats far back because they size down in frames in order to get lower headtubes. If you read my post I explain that getting lower is always more aerodynamic. Shorter headtubes are lower which is why they choose smaller frames. The trade-off with smaller frames is not enough to reach which they facilitate with pushing their saddles back.
We agree here.

I am guessing that OP is not a pro and does not spend 8 hours a day on his bike during the offseason to change the muscle groups that he can use while cycling.
Some people ride over 20,000kms a year and aren't pro, (like me) don't presume to know who the OP is, he may be into Yoga and be flexible or just naturally flexible, try slammed, if it works, keep it.

They run their saddles forward on TT bikes to open their hip angle allowing them to get more aero.
No, the design of a TT bike is different and has different rules. The saddle is placed in a maximum power postition, but at the same time the body is place in a mximum aero position.

You start a fight and then claim you're wasting your time arguing with me? Duh.
All you did was call me out 'for being wrong' because it's different from what you read on the internet the other day. When you have very little riding experience, it seems.

But so what if I'm wrong? It's not your freaking place to correct me. Someone else with detailed knowledge and experience can do that. Not a whiny little cut and pate keyboard warrior. Earn your stripes, then I'll listen to you.

icantaffordcycling
Posts: 216
Joined: Wed Jan 09, 2019 5:03 am

by icantaffordcycling

So unless I am an 8 w/kg rider the facts that I bring up are worthless? I can cite papers and articles from people that have earned their stripes but then you would just call me a "whiny little cut and paste keyboard warrior". You are too easy.
:thumbup:
Edit: Spelling.

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Lewn777
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Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

I'm done here.

Please just reply to threads and address your posts to the OP in order to help them. They can read through and decide the merit of the posts, they are adults too, they don't need to be protected by you, from what you deem 'misinformation'. You are not the internet police.

Some people have lots more experience than you do. At first it seems that they are wrong because you read something different somewhere, but sometimes they're mixing personal experience with 100s of things they've read and seen. Sometimes they express ideas poorly, but it doesn't make them low-hanging fruit for you to pick.

It's not maths class, lots of experts even disagree there's often no one answer, better to agree to disagree than start a flame war.

'Calling out' other people because in your opinion they are wrong it won't help anyone. You'll just derail the thread with flaming. Then the OP has to read through anger, childishness and pettiness to find information, and it's embarassing for all concerned. When was the last time someone on a web forum appologized? Never happens. It just escalates.

Hexsense
Posts: 810
Joined: Wed Dec 30, 2015 12:41 am

by Hexsense

Lewn777 wrote:
Fri May 17, 2019 6:18 am
They run their saddles forward on TT bikes to open their hip angle allowing them to get more aero.
No, the design of a TT bike is different and has different rules. The saddle is placed in a maximum power postition, but at the same time the body is place in a mximum aero position.
Weird concept. Get both max aero and max power in one position?
What's the catch of not adopting that position on road bike too... just suffered bike handling?, totally worth the trade then.

How many people can put out more power in TT position than on road bike?
All people i know personally are opposite, can put out more power on road bike than on TT bike. TT bike is faster just because they are much more aero. So faster despite less power output.

What i find about seat forward for max power is complete reverse. More set-back allow me to engage more glute muscle, easier to generate power. However, it close down hip angle thus harder to stay aero. Push the seat forward make it easier to get low, but quad needs to work more to compensate for less glute power, also more energy wasted to support upper body as i'm less balanced on the bike.


Lewn777 wrote:
Fri May 17, 2019 6:18 am
1. My point was that adapting between a reasonably sized stem which I believe to be between 80-130 to facilitate a better bike fit is worth the small change in handling.
Wrong, the change in handling is massive, he should be deciding between 100-110-120 nothing outside that range. With this it really seems like you have no experience or clue what you're talking about.
Change in stem length has noticeable effect to bike handling, especially in one of these condition:
1.) It is so long that you are uncomfortable reaching far when the bar rotate.
2.) It is so short that gap between front of the knee and the bar are low. It doesn't have to hit, but being close to each other when standing is already make weight balance feel weird.

Shifter hood length: 5cm+ (more like 8-10, but we place hand well behind the lever)
Bar reach: 7cm+
Simple sum of front rotating reach, not doing more accurate triangle calculation for actual angle.
Combined reach of 80mm stem: 80+50+70=200 . Combined reach of 130mm stem: 130+50+70=250.
The difference is about a quarter longer reach on the 130mm stem. Yeah, 25% difference can be count as massive.

You know what can make more difference in bike handling than stem length?
Trail number.
Something riders of medium-large size never have to think about as most of the bike have 73degree HTA, and 43-45mm fork offset universally.
However, on XS, S bikes, it usually have to be compromised. Some bike maintain good trail number on small bike better than the others (usually those with more than one fork across sizes).

So in case of 100mm stem on XS size (-10degree stem or less) or 90mm on S size (-17degree stem), given typical Giant geometry with one fork across all sizes and XS head tube is much slacker,
The 90mm with S size will handle better despite shorter stem.
Sure, this doesn't apply for the OP at 5'11 at all, just an example of other things to care more than few percent different in front end length.
Last edited by Hexsense on Fri May 17, 2019 7:36 am, edited 1 time in total.

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Lewn777
Posts: 725
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

Hexsense wrote:
Fri May 17, 2019 7:14 am
Lewn777 wrote:
Fri May 17, 2019 6:18 am
They run their saddles forward on TT bikes to open their hip angle allowing them to get more aero.
No, the design of a TT bike is different and has different rules. The saddle is placed in a maximum power postition, but at the same time the body is place in a mximum aero position.
Weird concept. Get both max aero and max power in one position?
What's the catch of not adopting that position on road bike too... just suffered bike handling?, totally worth the trade then.

How many people can put out more power in TT position than on road bike?
All people i know personally are opposite, can put out more power on road bike than on TT bike. TT bike is faster just because they are much more aero. So faster despite less power output.

What i find about seat forward for max power is complete reverse. More set-back allow me to engage more glute muscle, easier to generate power. However, it close down hip angle thus harder to stay aero. Push the seat forward make it easier to get low, but quad needs to work more to compensate for less glute power, also more energy wasted to support upper body as i'm less balanced on the bike.
Yes you're right, you put out less power on a TT bike because the whole bike is designed towards being aero so you lose on power due to arm position hurting cardio rather than leg position.

Well there's a sweet-spot above the cranks at which you can generate max power, too far forward or too far rearward you're going to lose power. I love long and low on a smaller frame regardless. 110-120 stem, seat most of the way back on a bike a bit smaller than ideal. It doean't matter for me as I use an Arione 00, it's a really long saddle so you can choose your position fore or aft pretty much.


The OP has a M/L bike so in this case 100-120mm stem would be ideal.

Hexsense
Posts: 810
Joined: Wed Dec 30, 2015 12:41 am

by Hexsense

We all may disagree on some trade-off(s).

But agree about sweet spot.
Somewhere balance for
Hip angle vs Front-Rear weight balance
Aero vs conserve energy from upper body supporting weight
Quad engagement vs Glutes engagement.

devonbiker
Posts: 70
Joined: Wed May 30, 2018 1:26 pm

by devonbiker

Lewn777 wrote:
Fri May 17, 2019 6:18 am
icantaffordcycling wrote:
Fri May 17, 2019 5:56 am
Lewn777 wrote:
Fri May 17, 2019 5:20 am
Somewhere between 80-130mm stem hat the heck? That's like picking a random stem!
Pros often run their seats far back in the peloton because it's more aero, they also run far more forward for power as with TT bikes. It's a simple will known observation.
Please, by all means, write your opinion (not that there's any point because you can find it in 0.000004 seconds with a search engine). But please refrain from attacking other people's opinions, or we're going to be in flame wars until one of us gets banned.
1. My point was that adapting between a reasonably sized stem which I believe to be between 80-130 to facilitate a better bike fit is worth the small change in handling.
Wrong, the change in handling is massive, he should be deciding between 100-110-120 nothing outside that range. With this it really seems like you have no experience or clue what you're talking about.


2. Pros run their seats far back because they size down in frames in order to get lower headtubes. If you read my post I explain that getting lower is always more aerodynamic. Shorter headtubes are lower which is why they choose smaller frames. The trade-off with smaller frames is not enough to reach which they facilitate with pushing their saddles back.
We agree here.

I am guessing that OP is not a pro and does not spend 8 hours a day on his bike during the offseason to change the muscle groups that he can use while cycling.
Some people ride over 20,000kms a year and aren't pro, (like me) don't presume to know who the OP is, he may be into Yoga and be flexible or just naturally flexible, try slammed, if it works, keep it.

They run their saddles forward on TT bikes to open their hip angle allowing them to get more aero.
No, the design of a TT bike is different and has different rules. The saddle is placed in a maximum power postition, but at the same time the body is place in a mximum aero position.

You start a fight and then claim you're wasting your time arguing with me? Duh.
All you did was call me out 'for being wrong' because it's different from what you read on the internet the other day. When you have very little riding experience, it seems.

But so what if I'm wrong? It's not your freaking place to correct me. Someone else with detailed knowledge and experience can do that. Not a whiny little cut and pate keyboard warrior. Earn your stripes, then I'll listen to you.
I may not be a Pro, but I am the same age and weight as Chris Froome, with a BMI of 20. I am a primarily a runner (my main sport). I want to set up my bike for speed, but my legs are weak. I have been gradually slamming the stem over the past year and have preferred the new position each time I lower it. I have ordered a 110mm stem as I have noticed since having only 17mm spacers (compared to 45mm) below the stem I am can now just about see the front wheel hub in front of the handlebar when my hands are on the hoods (my normal riding position).

I have a climbing bike and climbing wheels, and climbing is probably my strong point, so would the longer stem make climbing out of the saddle harder?

User avatar
Lewn777
Posts: 725
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

devonbiker wrote:
Fri May 17, 2019 9:55 am
Lewn777 wrote:
Fri May 17, 2019 6:18 am
icantaffordcycling wrote:
Fri May 17, 2019 5:56 am
Lewn777 wrote:
Fri May 17, 2019 5:20 am
Somewhere between 80-130mm stem hat the heck? That's like picking a random stem!
Pros often run their seats far back in the peloton because it's more aero, they also run far more forward for power as with TT bikes. It's a simple will known observation.
Please, by all means, write your opinion (not that there's any point because you can find it in 0.000004 seconds with a search engine). But please refrain from attacking other people's opinions, or we're going to be in flame wars until one of us gets banned.
1. My point was that adapting between a reasonably sized stem which I believe to be between 80-130 to facilitate a better bike fit is worth the small change in handling.
Wrong, the change in handling is massive, he should be deciding between 100-110-120 nothing outside that range. With this it really seems like you have no experience or clue what you're talking about.


2. Pros run their seats far back because they size down in frames in order to get lower headtubes. If you read my post I explain that getting lower is always more aerodynamic. Shorter headtubes are lower which is why they choose smaller frames. The trade-off with smaller frames is not enough to reach which they facilitate with pushing their saddles back.
We agree here.

I am guessing that OP is not a pro and does not spend 8 hours a day on his bike during the offseason to change the muscle groups that he can use while cycling.
Some people ride over 20,000kms a year and aren't pro, (like me) don't presume to know who the OP is, he may be into Yoga and be flexible or just naturally flexible, try slammed, if it works, keep it.

They run their saddles forward on TT bikes to open their hip angle allowing them to get more aero.
No, the design of a TT bike is different and has different rules. The saddle is placed in a maximum power postition, but at the same time the body is place in a mximum aero position.

You start a fight and then claim you're wasting your time arguing with me? Duh.
All you did was call me out 'for being wrong' because it's different from what you read on the internet the other day. When you have very little riding experience, it seems.

But so what if I'm wrong? It's not your freaking place to correct me. Someone else with detailed knowledge and experience can do that. Not a whiny little cut and pate keyboard warrior. Earn your stripes, then I'll listen to you.
I may not be a Pro, but I am the same age and weight as Chris Froome, with a BMI of 20. I am a primarily a runner (my main sport). I want to set up my bike for speed, but my legs are weak. I have been gradually slamming the stem over the past year and have preferred the new position each time I lower it. I have ordered a 110mm stem as I have noticed since having only 17mm spacers (compared to 45mm) below the stem I am can now just about see the front wheel hub in front of the handlebar when my hands are on the hoods (my normal riding position).

I have a climbing bike and climbing wheels, and climbing is probably my strong point, so would the longer stem make climbing out of the saddle harder?
There are so many variables. How tall are you first of all?

My opinion, if a non-extreme pro-type position is comfortable for you, go for it. By that I mean go down a size in frame, run a longer stem slammed and run a -17 degree stem. Obviously do it in incriments. Sometimes even though a lower/and or longer position feels OK it may be pointless if you just end up sat on the hoods all day, you've got to be able to ride in the drops all day, and descend on them.

If you are on a recommended 'perfect' frame for you (not a smaller than you're supposed to be on) a longer stem could be a bit too long for you, instead try slamming the stem and running a more aggressive degree angle -17 instead of -6 or -7 first before trying to go longer as this will have an effect of increasing the reach.

I think sitting up higher with a shorter overall reach and being less aero helps climbing and hurts aero a bit, but it's not a big deal.
Stood up climbing I doubt there's much difference. When I rented a Trek Emonda I found it to be very 'sat up' and it climbed very well, but I wouldn't really like it like that on the flat, but then it was a 54 with a 10cm stem and a longer stem could have made it more aero.

I'll give you another example I'm 183cm (6ft) and my official size frame is usually 56cm. However to me being from a MTB background 56cm feels too big for me and to avoid feeling too stretched out I would on most bikes drop down to a 10cm stem, but this isn't always the case as different manufacturers have different geo, so frame and bar reach can change perceptions.

On a rental 54cm Tarmac I felt a 10cm stem was far too short, whereas normally I just find it not quite right. But of course it was a rental and not slammed and only a 6 or 7 degree stem, but I would have loved a 12cm stem on that bike. I also rented a 56cm frame Tarmac the next week and felt I wanted that shorter 10cm stem on there.

On my current 54cm frame I put an older PRO Stealth 10cm stem on there because the 12cm stem was leaving nasty indents on the steerer. 10cm is definately too short for me, but in terms of pure climbing and nothing else it helps marginally as the more upright seated position torso gives better cardio performance or seems to (maybe in my head). 12cm maybe was a tad too long as I got that stem for an old 52-53cm frame, and 11cm is the sweetspot for me on this bike. You've got to ride lots of bikes and change set-ups to get a feel for exactly what suits you.

These are all my thoughts, I'm not an expert, but I hope it gives you a few ideas and just experiment with them. If you are about 6ft tall I would say you can pretty much forget any stem over 120mm or under 100mm on most modern frames.

If anyone else thinks I'm wrong that's fine, but attacking my post isn't very polite. Instead just state your own opinion and why you think it's correct from your perspective.

devonbiker
Posts: 70
Joined: Wed May 30, 2018 1:26 pm

by devonbiker

Lewn777 wrote:
Fri May 17, 2019 11:45 am
devonbiker wrote:
Fri May 17, 2019 9:55 am
Lewn777 wrote:
Fri May 17, 2019 6:18 am
icantaffordcycling wrote:
Fri May 17, 2019 5:56 am


1. My point was that adapting between a reasonably sized stem which I believe to be between 80-130 to facilitate a better bike fit is worth the small change in handling.
Wrong, the change in handling is massive, he should be deciding between 100-110-120 nothing outside that range. With this it really seems like you have no experience or clue what you're talking about.


2. Pros run their seats far back because they size down in frames in order to get lower headtubes. If you read my post I explain that getting lower is always more aerodynamic. Shorter headtubes are lower which is why they choose smaller frames. The trade-off with smaller frames is not enough to reach which they facilitate with pushing their saddles back.
We agree here.

I am guessing that OP is not a pro and does not spend 8 hours a day on his bike during the offseason to change the muscle groups that he can use while cycling.
Some people ride over 20,000kms a year and aren't pro, (like me) don't presume to know who the OP is, he may be into Yoga and be flexible or just naturally flexible, try slammed, if it works, keep it.

They run their saddles forward on TT bikes to open their hip angle allowing them to get more aero.
No, the design of a TT bike is different and has different rules. The saddle is placed in a maximum power postition, but at the same time the body is place in a mximum aero position.

You start a fight and then claim you're wasting your time arguing with me? Duh.
All you did was call me out 'for being wrong' because it's different from what you read on the internet the other day. When you have very little riding experience, it seems.

But so what if I'm wrong? It's not your freaking place to correct me. Someone else with detailed knowledge and experience can do that. Not a whiny little cut and pate keyboard warrior. Earn your stripes, then I'll listen to you.
I may not be a Pro, but I am the same age and weight as Chris Froome, with a BMI of 20. I am a primarily a runner (my main sport). I want to set up my bike for speed, but my legs are weak. I have been gradually slamming the stem over the past year and have preferred the new position each time I lower it. I have ordered a 110mm stem as I have noticed since having only 17mm spacers (compared to 45mm) below the stem I am can now just about see the front wheel hub in front of the handlebar when my hands are on the hoods (my normal riding position).

I have a climbing bike and climbing wheels, and climbing is probably my strong point, so would the longer stem make climbing out of the saddle harder?
There are so many variables. How tall are you first of all?

My opinion, if a non-extreme pro-type position is comfortable for you, go for it. By that I mean go down a size in frame, run a longer stem slammed and run a -17 degree stem. Obviously do it in incriments. Sometimes even though a lower/and or longer position feels OK it may be pointless if you just end up sat on the hoods all day, you've got to be able to ride in the drops all day, and descend on them.

If you are on a recommended 'perfect' frame for you (not a smaller than you're supposed to be on) a longer stem could be a bit too long for you, instead try slamming the stem and running a more aggressive degree angle -17 instead of -6 or -7 first before trying to go longer as this will have an effect of increasing the reach.

I think sitting up higher with a shorter overall reach and being less aero helps climbing and hurts aero a bit, but it's not a big deal.
Stood up climbing I doubt there's much difference. When I rented a Trek Emonda I found it to be very 'sat up' and it climbed very well, but I wouldn't really like it like that on the flat, but then it was a 54 with a 10cm stem and a longer stem could have made it more aero.

I'll give you another example I'm 183cm (6ft) and my official size frame is usually 56cm. However to me being from a MTB background 56cm feels too big for me and to avoid feeling too stretched out I would on most bikes drop down to a 10cm stem, but this isn't always the case as different manufacturers have different geo, so frame and bar reach can change perceptions.

On a rental 54cm Tarmac I felt a 10cm stem was far too short, whereas normally I just find it not quite right. But of course it was a rental and not slammed and only a 6 or 7 degree stem, but I would have loved a 12cm stem on that bike. I also rented a 56cm frame Tarmac the next week and felt I wanted that shorter 10cm stem on there.

On my current 54cm frame I put an older PRO Stealth 10cm stem on there because the 12cm stem was leaving nasty indents on the steerer. 10cm is definately too short for me, but in terms of pure climbing and nothing else it helps marginally as the more upright seated position torso gives better cardio performance or seems to (maybe in my head). 12cm maybe was a tad too long as I got that stem for an old 52-53cm frame, and 11cm is the sweetspot for me on this bike. You've got to ride lots of bikes and change set-ups to get a feel for exactly what suits you.

These are all my thoughts, I'm not an expert, but I hope it gives you a few ideas and just experiment with them. If you are about 6ft tall I would say you can pretty much forget any stem over 120mm or under 100mm on most modern frames.

If anyone else thinks I'm wrong that's fine, but attacking my post isn't very polite. Instead just state your own opinion and why you think it's correct from your perspective.
I am 5"11 so a little shorter than froomie ;-)

I agree that 100 or 110mm stem would be ideal, I will experiment with the 110m with the slammed stem - when I first tried it with a high stem it did feel stretched though and found myself putting my hands on the bars a lot. But that was a year ago.

User avatar
Lewn777
Posts: 725
Joined: Thu Mar 09, 2017 5:35 am

by Lewn777

devonbiker wrote:
Fri May 17, 2019 12:54 pm
Lewn777 wrote:
Fri May 17, 2019 11:45 am
devonbiker wrote:
Fri May 17, 2019 9:55 am
Lewn777 wrote:
Fri May 17, 2019 6:18 am


I may not be a Pro, but I am the same age and weight as Chris Froome, with a BMI of 20. I am a primarily a runner (my main sport). I want to set up my bike for speed, but my legs are weak. I have been gradually slamming the stem over the past year and have preferred the new position each time I lower it. I have ordered a 110mm stem as I have noticed since having only 17mm spacers (compared to 45mm) below the stem I am can now just about see the front wheel hub in front of the handlebar when my hands are on the hoods (my normal riding position).

I have a climbing bike and climbing wheels, and climbing is probably my strong point, so would the longer stem make climbing out of the saddle harder?
There are so many variables. How tall are you first of all?

My opinion, if a non-extreme pro-type position is comfortable for you, go for it. By that I mean go down a size in frame, run a longer stem slammed and run a -17 degree stem. Obviously do it in incriments. Sometimes even though a lower/and or longer position feels OK it may be pointless if you just end up sat on the hoods all day, you've got to be able to ride in the drops all day, and descend on them.

If you are on a recommended 'perfect' frame for you (not a smaller than you're supposed to be on) a longer stem could be a bit too long for you, instead try slamming the stem and running a more aggressive degree angle -17 instead of -6 or -7 first before trying to go longer as this will have an effect of increasing the reach.

I think sitting up higher with a shorter overall reach and being less aero helps climbing and hurts aero a bit, but it's not a big deal.
Stood up climbing I doubt there's much difference. When I rented a Trek Emonda I found it to be very 'sat up' and it climbed very well, but I wouldn't really like it like that on the flat, but then it was a 54 with a 10cm stem and a longer stem could have made it more aero.

I'll give you another example I'm 183cm (6ft) and my official size frame is usually 56cm. However to me being from a MTB background 56cm feels too big for me and to avoid feeling too stretched out I would on most bikes drop down to a 10cm stem, but this isn't always the case as different manufacturers have different geo, so frame and bar reach can change perceptions.

On a rental 54cm Tarmac I felt a 10cm stem was far too short, whereas normally I just find it not quite right. But of course it was a rental and not slammed and only a 6 or 7 degree stem, but I would have loved a 12cm stem on that bike. I also rented a 56cm frame Tarmac the next week and felt I wanted that shorter 10cm stem on there.

On my current 54cm frame I put an older PRO Stealth 10cm stem on there because the 12cm stem was leaving nasty indents on the steerer. 10cm is definately too short for me, but in terms of pure climbing and nothing else it helps marginally as the more upright seated position torso gives better cardio performance or seems to (maybe in my head). 12cm maybe was a tad too long as I got that stem for an old 52-53cm frame, and 11cm is the sweetspot for me on this bike. You've got to ride lots of bikes and change set-ups to get a feel for exactly what suits you.

These are all my thoughts, I'm not an expert, but I hope it gives you a few ideas and just experiment with them. If you are about 6ft tall I would say you can pretty much forget any stem over 120mm or under 100mm on most modern frames.

If anyone else thinks I'm wrong that's fine, but attacking my post isn't very polite. Instead just state your own opinion and why you think it's correct from your perspective.
I am 5"11 so a little shorter than froomie ;-)

I agree that 100 or 110mm stem would be ideal, I will experiment with the 110m with the slammed stem - when I first tried it with a high stem it did feel stretched though and found myself putting my hands on the bars a lot. But that was a year ago.
It sounds like 100mm slammed is best for you, but try 110mm.

jih
Posts: 244
Joined: Fri Jan 29, 2016 12:54 pm

by jih

Back to the OP: 100mm and 110mm stems aren’t drastically different, and stems aren’t difficult to swap. Just try both and see which you prefer? You may find there’s not much difference on the road.

I generally run 110mm, but sometimes swap to a 100mm and a few spacers for very long rides. I’m good on either.

Mr.Gib
Posts: 3559
Joined: Fri Mar 18, 2005 4:12 pm
Location: eh?

by Mr.Gib

To the OP, re stem length, don't sweat it. I rode various Giant TCR Advanced SL's for a few years (I am 183 cm - size ML) and I experimented quite a bit with different stem lengths. When you take your first ride on a shorter stem you notice the steering is a bit more reactive to bike movement, more so out of the saddle, but your body compensates for the change in about 5 minutes and it becomes a non-issue.

Get your saddle located appropriately and then choose the stem length that results in a position that works for you based on your priorities and what feels good for your body. Doing super long rides? You'll want it higher and shorter. Racing crits? Longer and lower. Bad back? Go back to the Defy. I do find it strange that people who are concerned about the aerodynamics of their position often set their bars so low that they can barely use the drops. You should be able to ride on the drops indefinitely in reasonable comfort. That's what the drops are for. And when it comes to aero, don't forget that your elbows also bend.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

by Weenie


DJT21
Posts: 313
Joined: Sun Mar 27, 2011 7:35 pm

by DJT21

Good grief, there's some rubbish posted on here. Has anyone considered what happens to the postion of the saddle and a riders mass in relation to the BB when they cycle uphill or downhill?! It changes!

If you've got short legs for your height then you may want to put the saddle further rearward, likewise, if you have long legs then a further forward position will likely work better. If you've got long legs and use the plumb line method, you'll end up with the saddle pushed right back, and hence your centre of mass way over the back wheel which will lead to poor handling and less weight on the pedals. And vice versa, short legs/long torso and you'll have your saddle really far forward and alot of weight on your hands/the handlebars; not great for comfort.

If you want to run a long/low stem, then a saddle further forward may help as it opens up the hips. See Niki Terpstra, Adam Hansen and no doubt loads of new riders that I'm unfamiliar with.

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