# Will flipping my stem effect handling?



## choppedsled (Sep 18, 2008)

Are there any negative effects from flipping the stem on my Cervelo besides looking ugly? Will handling be effected? I'm playing with the fit a bit before I try swapping the stem. I'm looking for a bit more upright position, maybe closer while I build my endurance and flexability. Deda Newton 100mm.

Thanks


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## David Kirk (Mar 6, 2005)

Yes it will affect the handling somewhat. The hard thing to predict is how much it will change and how you will feel about it. Like everything else it's a compromise......... gain a bit of comfort and lose a bit on handling. The only way to see how it feels would be to try it and see what you get.

It will most likely have the largest effect at high speeds when the tracking might not be as good because you've taken some weight off the front wheel and moved it to the rear.

The proof will be in the putting.

dave


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## roadfix (Jun 20, 2006)

Handling difference, while there, will be insignificant to the average recreational rider.


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## Stogaguy (Feb 11, 2006)

*Just flip it and see...*

David Kirk is correct in his assessment of the effect, but I would point out that the difference will be very small. With the stem flipped, your setup will still be well within the envelope of acceptable solutions. If the setup fits you better, you will probably be more comfortalbe on the bike. This increased comfort may actually lead to the perception (on your part) that the change improved the handling. 

Bottom line, flip it and see. What is the worst that could happen? If you do not like it, you can always change it back.


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## PJ352 (Dec 5, 2007)

I'm in the minority here because I don't believe it's going to affect handling, at least not to any discernable degree. It is, effectively doing the same as adding a cm or two to the HT length and more and more manufacturers are doing that (Trek Madone pro/ performance / Cervelo R3/ RS come to mind) without otherwise changing the frame geo or adversely affecting handling. Additionally, you're not redistributing weight rearward because the saddle (and your position on it) remains static.

You do change _stack_, but that only affects _reach_ by a few mm's.


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## crispy010 (Jan 26, 2009)

I flipped mine the other way, to lower my bars, and I did notice a change in handling: it became more precise, sharper. I like the result. 

My point is stems do affect handling, but it's a small change. While you may notice it, it won't throw you off.

Your bike should handle just fine with a more upright stem. Go for it, if it will make you comfortable!


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## Andrea138 (Mar 10, 2008)

Much to the dismay of fellow racers, I flipped mine a few months ago when I rotated a segment in my neck (off the bike). I didn't notice anything except that my neck didn't hurt anymore on long rides.


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## Mr. Versatile (Nov 24, 2005)

I think the effect, if any, will be completely unnoticable. Bicycles do not steer by turning the handlebars, so neither the length, nor the angle of the stem will make any difference except to your comfort level.


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## Mapei (Feb 3, 2004)

As David Kirk says, the bike'll be a little more nervous and tiggly. A_ little _more.


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## acid_rider (Nov 23, 2004)

Floyd Landis rode with a flipped up stem on his BMC during the year he won and then lost Tour De France. So if a flipped up stem is more comfortable for you then go for it. And next time buy a bike with a taller head tube assuming everyhing else fits you, such as all important seat tube angle (there are quite a few now with tall head tubes).


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## brblue (Jan 28, 2003)

*Nope*

Despite my drawing talents, I hope the picture reveals the following:

- Let's say you have a 130 mm threadless stem, with an angle of -17 deg (or 73 deg). Let's say that the Headtube angle of the frame is 73 deg. Then, having a "flipped up" stem is the same as a "flipped down" stem + 76 mm of spacers.
(spacer height is 2*(130 mm *sin 17 deg) ).

- In case of EACH stem (not only of our particular case here), flipping it up does not change the effective LEVER you have upon the fork .
That lever is in this case, 130 mm * cos 17 deg = 124 mm => in this particular case, installing the 130 mm , -17 deg stem , in up / down position is THE SAME as installing an 124mm, 0 deg stem

Any change in steering is derived from the way you steer your bike when your position is more upright or not.
In both cases (stem flipped up / down) the bars oppose the same resistance while steering.


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## Maximus_XXIV (Nov 10, 2008)

I would guess that it would change your weight distribution by a few grams depending on how much higher or lower your bars became.


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## David Kirk (Mar 6, 2005)

Maximus_XXIV said:


> I would guess that it would change your weight distribution by a few grams depending on how much higher or lower your bars became.


I think you are on the right track. The biggest thing that happens is a change in weight distribution. It's not a big change but I'll bet most folks would feel it. That's not to say it would be a bad feeling but it would be different. Hell, it could be better handling depending on you and your intended use of the bike.

Anyway you cut it it will move some weight from the front wheel to the rear. With most stems it's a very easy and free experiment so give it a try and see what you get. Give it a few rides to let yourself get used to the different position and if in the end you don't like it you can put it back. No harm no foul.

dave


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## roadfix (Jun 20, 2006)

The bottom line is any change in handling characteristics, if any, you will quickly re-adapt and won't even notice the difference.


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## Peanya (Jun 12, 2008)

Truth: it won't affect the handling. It will affect the fit, which will have an effect on handling. For the better or worse depends on if the fit is better or worse.


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## David Kirk (Mar 6, 2005)

Peanya said:


> Truth: it won't affect the handling. It will affect the fit, which will have an effect on handling. For the better or worse depends on if the fit is better or worse.


Aren't they two side of the same coin?

Dave


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## Kerry Irons (Feb 25, 2002)

*Putting out?*



David Kirk said:


> The proof will be in the putting.


Pudding? Or are you "putting out" in some way?


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## David Kirk (Mar 6, 2005)

Kerry Irons said:


> Pudding? Or are you "putting out" in some way?


Maybe I'm putting out pudding?

Dave


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## Mr. Versatile (Nov 24, 2005)

I repeat: Bicycles don't steer by turning the handlebars. This is a fact, not conjecture. Therefore the length or angle of the stem will make no difference except to your comfort preferences.


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## David Kirk (Mar 6, 2005)

Mr. Versatile said:


> I repeat: Bicycles don't steer by turning the handlebars. This is a fact, not conjecture. Therefore the length or angle of the stem will make no difference except to your comfort preferences.


I disagree.

You are absolutely correct that bikes are steered by turning the bars (except at walking speed and below) but are instead turned by leaning and they are in fact leaned by countersteering.

One big factor in the way a bike responds to countersteering is the combination of the amount of trail the bike has along with the amount of weight is on the front wheel to enact the self correction tendency of the trail. In words even I can understand when you put more weight on the front wheel it wants to go more straight and it will have more tendency to come out of turn once started. This is one of the reasons french type touring bikes are made with very low amounts of trail because they are most often set up with a large handlebar bag that has a good bit of weight in it which helps the bike become more stable. If they put 6.0cm of trail on them they would be very hard to turn.

So in this way stem length and angle have an effect. Reducing handlebar drop will shift weight from the front to the rear and will take a bit of the self correction tendency out of the steering.

We have all felt this at one time or another. When going downhill fast we crouch forward and get low. We might do this for less aerodynamic drag at times but we also do it to get more stability. Crouching forward moves weigh onto the front wheel which makes it more resistant to changing direction. Try going down a fast steep hill sometime sitting up nice and tall and see how that feels and compare it to leaning forward and putting more weight on that front wheel. Given the choice I suspect I know which position you'll choose. This is also why some bikes become so unstable when you sit up very tall to take off a vest or open a powerbar. Not enough weight on the front wheel to make the bike stable.

The length of the stem has less bearing in most cases on fore-aft weight distribution as it takes a big stem length difference to get the same effect as a small amount of stem angle change. Stem length does however make a bike more or less stable because it places the hands closer to, or further from the steering axis in effect giving a longer or shorter lever to counteract the forces involved. This is one reason why you so often see pro team bikes with such longs stems. It's not because the top tube was too short..... if that was the case they'd make the top tubes longer. It's to get the extra leverage needed for high speed stability. You'll even see the smallest guys riding around with really short top tubes and 130mm stems. You will almost never see a pro bike with a stem below 110mm no matter what and many use stems not sold to the public that are 140 -150mm long.

So that's the long way of telling you I disagree.

dave


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## JCavilia (Sep 12, 2005)

*I find this amusing,*

as a retro-grouch who thinks we'd be better off if we'd stayed with quill stems. Many people with quill stems routinely adjusted the height of the bars for different conditions. For example, it was common to start the season with the bars higher than usual, and then lower them as you regained fitness and flexibility. In my experience. while changing stem _length_ has some small effect on handling, changing height has almost none, except to the extent weight distribution is changed (and weight distribution changes constantly with riding position, anyway). 

I think the only reason this question comes up now is because changing bar height has been turned into a major operation (often involving buying new parts), rather than a 10-second job with a 5-mm allen wrench.

End of retro-rant.


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## buck-50 (Sep 20, 2005)

JCavilia said:


> as a retro-grouch who thinks we'd be better off if we'd stayed with quill stems. Many people with quill stems routinely adjusted the height of the bars for different conditions. For example, it was common to start the season with the bars higher than usual, and then lower them as you regained fitness and flexibility. In my experience. while changing stem _length_ has some small effect on handling, changing height has almost none, except to the extent weight distribution is changed (and weight distribution changes constantly with riding position, anyway).
> 
> I think the only reason this question comes up now is because changing bar height has been turned into a major operation (often involving buying new parts), rather than a 10-second job with a 5-mm allen wrench.
> 
> End of retro-rant.


Preach on, Brutha.


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## function (Jun 20, 2008)

If changing stem height is something you do on a regular basis, then yes it's a major operation. I would suspect that most folks have their position dialed in after a few years.


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## buck-50 (Sep 20, 2005)

function said:


> If changing stem height is something you do on a regular basis, then yes it's a major operation. I would suspect that most folks have their position dialed in after a few years.


I dunno, I've been riding for many years and I still tinker with my position from time to time.

Personally, I prefer the versatility of being able to have my position dialed in AND being able to change the stem height as need be without needing to buy a new fork or stem.

YMMV.


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## Bob Ross (Apr 18, 2006)

^^^ But geometrically speaking aren't you also changing the virtual stem length whenever you change the height of quill stem?


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## heathb (Nov 1, 2008)

David Kirk said:


> I disagree.
> 
> We have all felt this at one time or another. When going downhill fast we crouch forward and get low. We might do this for less aerodynamic drag at times but we also do it to get more stability. Crouching forward moves weigh onto the front wheel which makes it more resistant to changing direction. Try going down a fast steep hill sometime sitting up nice and tall and see how that feels and compare it to leaning forward and putting more weight on that front wheel. Given the choice I suspect I know which position you'll choose. This is also why some bikes become so unstable when you sit up very tall to take off a vest or open a powerbar. Not enough weight on the front wheel to make the bike stable.
> 
> ...


Thanks for the post. I've been experimenting with different stem lengths for a long time and have been buying longer and longer stems without really knowing why. 

At first the shorter stems in the upright position was what I wanted. Then years ago I started racing and noticed that a lot of guys had really long stems that were angles downward. I didn't think much about it until I tried it myself. Took some time to get used to having my weight forward like that. I think some guys simply can't get used to the extreme set ups that some racers use. Also helps if you upper body is slim and trim with strong arms. 

I now tend to think of an upright stem the same as driving a big bus, it's not as stable because you're center of gravity is higher. Downhill skiers are tucked low for a reason, recreational skiers wouldn't have to worry about this.


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## JCavilia (Sep 12, 2005)

Bob Ross said:


> ^^^ But geometrically speaking aren't you also changing the virtual stem length whenever you change the height of quill stem?


Yeah, but not much. And the change is in a logical direction: if you want the bar higher because of limited flexibility, it makes sense to want a little shorter horizontal reach. Same for the converse situation of lowering the bar for a more aero position -- it makes sense to increase reach slightly, since lowering your torso to a more horizontal position will move your arms and shoulders forward..


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## tarwheel2 (Jul 7, 2005)

*handling*



roadfix said:


> The bottom line is any change in handling characteristics, if any, you will quickly re-adapt and won't even notice the difference.


Correct. If you notice a difference after the first ride, you may rival the "princess and the pea."


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## danl1 (Jul 23, 2005)

buck-50 said:


> I dunno, I've been riding for many years and I still tinker with my position from time to time.
> 
> Personally, I prefer the versatility of being able to have my position dialed in AND being able to change the stem height as need be without needing to buy a new fork or stem.
> 
> YMMV.


Yeah, but the grouchies go a little far with this argument. 

After all, it is _possible_ to put spacers on top of the stem. If a bike is built such that it has a few cm's of spacers under a 'down' stem when in a fairly neutral position, shifting and flipping allows all the flexibility (and more) that quills ever did. 

Doesn't much suit folks who ride for fashion, tho.


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## danl1 (Jul 23, 2005)

I'm _really_ stepping out on a limb here, but I'm going to kinda-sorta disagree with Dave. 

Weight distribution on the bike matters, but I'm convinced that it's through somewhat different mechanisms. To start, consider the experience of riding no-handed. It's very hard to ride stably with the hands just hovering above the bars. But sit way upright or lean back as is commonly seen in the pro victory salutes, and it's quite easy to keep the bike on line and stable.

Consider too, the high-speed descent. As Dave says, getting low over the front of the bike appears to firm it up a lot - uncomfortably so on a technical descent. Many folks, myself included, purposely slide well aft to restore steering balance. It also allows a lower position, save for that wacky sitting on the top tube and grabbing the stem trick that some use. 

Consider also, the mechanisms DH'ers employ: There are all sorts of tricks to drop seats and rail them back to improve downhill handling, but none to stretch out the stem or otherwise move forward to gain that effect. That's a tricky comparison for a few reasons, but I'll leave it in anyway. 

This creates a paradox: Shifting weight aft apparently makes steering more stable in one instance, and less in another. How to resolve?

I submit that it's not the weight distribution on the bike that is the primary driver, but the distribution of weight on the controls. That is, it matters less how much weight is on the front wheel, than how much is on the hands. If the upper body is busy holding up a significant portion of body weight, it's not capable of making the fine-level muscular controls necessary for smooth, confident bike handling, and the bike feels like it wants only to go straight. But get the weight off the hands, like a higher setup will tend to do, and the hands are again able to apply smooth response. It's not the trail you are fighting when weight is forward, but your own musculature!

Meanwhile the hands-free problem has a slightly less obvious solution: Shifting the weight either forward or aft has no practical effect on steering sensitivity unless there's way too little air in the tires and it changes trail - though that would be in the opposite direction to the experimental result. However, being upright raises the center of gravity, meaning that relatively smaller changes are needed to bring the bike underneath the rider, and increases the effective lever the rider has (though against the saddle rather than through the stem/bars.) Sitting up has the same effect as the longer stem that Dave mentions - it increases leverage to help with the steering.

I've played around with adjusting weight distribution by keeping the same body position, but fiddling with front center and chainstay length to adjust the balance. It was in imperfect experiment because messing with FC necessarily means fussing with head angles, stem lengths, and fork offsets to keep the trail consistant, and those have their own impacts. Also, I didn't have available a rack of custom frames for this trick - I messed with off-the-peg bits and pieces, which limited what I could do. Yes, weight distribution affects handling, and in the the directional ways we'd expect it to. But it's led me to the conclusion that bicycle weight distribution is far less important to handling perceptions than control weight distribution. 

I don't mean to argue, and perhaps I've simply gone into too much detail. But it's a discussion worth having, I think, because low positions aren't necessarily low-forward positions, and for some riders, it may be both more comfortable and more efficient to build a bike in a way different than the conventional wisdom might suggest. 

For example, someone with limited hamstring flexibility needs to get well forward to get conventionally flat, putting a lot of weight on the hands, and requiring a short top and long stem to compensate for the stiffness in the steering. That works, but it's not terribly comfortable and can lead to being way too far over the front when standing to climb. An alternative is to get the person a bit back/lower in the saddle, freeing the tightness in the back and allowing them to get low and flat without biasing their weight so much to the hands. That allows a more 'normal' set of TT and stem lengths, more balanced steering overall, and a better standing climbing position. The compromise is more emphasis on the glutes and (sometimes) a small decrease in power. That's not necessarily a negative, though - in the right situation, the enhanced comfort and lower overall position is worth the tradeoff. It also means that raising the stem and accepting the aerodynamic compromises that entails isn't necessarily the only path to increased comfort.

It's not for everyone or all situations, and I'm certainly not saying anyone (least of all Dave) is wrong. Just offering that there's more than one way to skin the apple.


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## crispy010 (Jan 26, 2009)

> Consider too, the high-speed descent. As Dave says, getting low over the front of the bike appears to firm it up a lot - uncomfortably so on a technical descent. Many folks, myself included, purposely slide well aft to restore steering balance. It also allows a lower position, save for that wacky sitting on the top tube and grabbing the stem trick that some use.


I dunno about you, but the reason I scoot back on a descent is to prevent myself from going over the bars should I have to brake hard for something (deer, pothole, turtle, etc). I've never felt that leaning further over the bars makes the front end too "firm". The only reason I get in the drops and get aero is to get better control of the bike (drops vs. hoods), and go faster.

I disagree with your conclusion that weight distribution does not affect handling. My commuter bike has a rack and a set of large axiom panniers. When those are loaded up with 30 lbs of textbooks and other stuff, the bike handles like it's on acid (slight exaggeration, but I like the expression): very squirrelly, and a lot more unstable than the unloaded bike. 

People who tour seriously get front racks and panniers for a reason: the weight needs to be distributed somewhat equally between the front and back wheels. This would indicate that weight distribution has a large impact on handling.



> Consider also, the mechanisms DH'ers employ: There are all sorts of tricks to drop seats and rail them back to improve downhill handling, but none to stretch out the stem or otherwise move forward to gain that effect. That's a tricky comparison for a few reasons, but I'll leave it in anyway.


DH'ers run a high risk of going over the bars for a couple of reasons. I would argue that their body position is dictated almost entirely by reducing the "endo" risk by getting the rider low behind the handlebars, so braking force pushes the rider into the bars, rather than pivoting them over the bars.


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