# headset spacers vs high rise handle bars?



## slingerzz (Dec 2, 2006)

is there a difference between using lets say a low rise (25mm) handle bar and having around 25mm of spacers under your stem compared to a high rise (50mm) handle bar and having no spacers under you stem? 

i know most people like their front end to be as low as possible... im not sure why exactly this is. I feel like i can jump/bunny hop better with the handlebars higher with some spacers under them. Could this have to do with the fact that I'm 6'2"? to be clear i am talking about on a 7in FR bike as well as a FR hardtail and not a dh race bike.


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## Rover Nick (Jul 13, 2006)

Personally, I think it looks really weird when I'm looking down to see 2" of spacers


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## 006_007 (Jan 12, 2004)

No difference. Your hands are going to be occupying the same piece of space providing both bars have the same sweep.



slingerzz said:


> is there a difference between using lets say a low rise (25mm) handle bar and having around 25mm of spacers under your stem compared to a high rise (50mm) handle bar and having no spacers under you stem? .


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## Hardtails Are Better (May 4, 2005)

In terms of fit, if your bars are at the same height, there's no difference. That said, it'd take more than 25mm of spacer to get a 25mm rise bar up to the level of a spacerless 50mm riser because the steerer tube isn't vertical, so not all of the spacer's length is pushing the bar up. I guess the version with spacers is also going to put the bar back just a little bit, but it's such a small difference I wouldn't worry about it.


I'd rather use a low rise bar and spacers, just because it gives you room to experiment/ change things for different situations. You can take out spacers, but making your bars have less rise is harder.


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## sittingduck (Apr 26, 2005)

Steer tube length may be a factor. A lot of hardtail riders nowadays are going to 2 and 3 inch rise bars. Seemed a bit much to me until I got a rigid fork and lost a couple inches of height in the front. Now a 2.5" rise is pretty much perfect. A taller stem height and low rise bars might be a little stiffer/stronger. Less bar tubing.


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## 501 (Jan 27, 2007)

the difference is that the stem sits closer to the fork/ headtube with tall bars, this set up will give you a better leverage point thus making it easier to pull up. if you run a tall spacer stack with low bars this set up will give you a longer leverage point feeling as if you have a really long top tube.


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## Huck Banzai (May 8, 2005)

501 said:


> the difference is that the stem sits closer to the fork/ headtube with tall bars, this set up will give you a better leverage point thus making it easier to pull up. if you run a tall spacer stack with low bars this set up will give you a longer leverage point feeling as if you have a really long top tube.


This seems to make sense to me - I have no formal engineering training, but living amongst architetcs/engineers I often get a good sense on these things.

I could never prove it though, does anyone qualified (you?) have any technical input?


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## colombo357 (Oct 31, 2007)

501 said:


> the difference is that the stem sits closer to the fork/ headtube with tall bars, this set up will give you a better leverage point thus making it easier to pull up.


That doesn't really make sense to me.

When your wheels are on the ground, your pivot point is at the rear axle. When you're in the air, your pivot point is somewhere around the BB.

Distance doesn't change from the pivot point to handlebars if the high rise bar and low rise + spacers end up in the same location.


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## Huck Banzai (May 8, 2005)

^^^^^^

Contrarian by Nature?

What I can say is it is different load dispersal -- next step goes to the actual engineers.


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## 501 (Jan 27, 2007)

colombo357 said:


> That doesn't really make sense to me.
> 
> When your wheels are on the ground, your pivot point is at the rear axle. When you're in the air, your pivot point is somewhere around the BB.
> 
> Distance doesn't change from the pivot point to handlebars if the high rise bar and low rise + spacers end up in the same location.


it does still change the actual leverage point, just as changing the pivot point on the linkage for rear suspension changes the leverage ratio of the shock. same basic princible


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## Rb (Feb 28, 2007)

Typically when a customer is unsure about fit and they have normal body proportions...

20mm under the stem
10mm on top
mid-rise bar

That pretty much covers your bases and allows for a good range of adjustability...unless you have a short torso and freakishly long arms... or vice versa.


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## CrustyOne (Oct 29, 2007)

501 said:


> the difference is that the stem sits closer to the fork/ headtube with tall bars, this set up will give you a better leverage point thus making it easier to pull up. if you run a tall spacer stack with low bars this set up will give you a longer leverage point feeling as if you have a really long top tube.


Huh???..a higher spacer stack gives you the feeling of a longer reach compared to a shorter stack and higher bar???

..if thats what your saying, I disagree

personaly I use spacers but If I wouldnt use a 2" stack of them, id find a bar that got me closer without that much spacer stacking


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## XSL_WiLL (Nov 2, 2004)

If your bar is in the exact same place, regardless of how it is achieved (bar or spacers), I don't see how the handling would be any different.


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## .Danno. (Jun 18, 2005)

XSL_WiLL said:


> If your bar is in the exact same place, regardless of how it is achieved (bar or spacers), I don't see how the handling would be any different.


Exactly.


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## Hardtails Are Better (May 4, 2005)

XSL_WiLL said:


> If your bar is in the exact same place, regardless of how it is achieved (bar or spacers), I don't see how the handling would be any different.


Argeed. It dosn't matter how the bar got to where it is. All that matters is its location. This applies to both handling and lofting the front wheel. I'm calling BS.


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## Huck Banzai (May 8, 2005)

Dont be quick to mske assertions with no foundation.I dont know HOW significant it is, but is most certainly not BS.

I used to take (and passed) this subject called physics, and noted along the way that there are many seemingly impossible things that are indeed possible given the right information.


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## njhcx4xlife (Jan 9, 2006)

The handling may be exactly the same when turning since your hands are in the same spot at the end result but the point in which the stem attached to the steerer tube and weight distribution has to have an effect on the leverage.


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## Hardtails Are Better (May 4, 2005)

Huck Banzai said:


> Dont be quick to mske assertions with no foundation.I dont know HOW significant it is, but is most certainly not BS.
> 
> I used to take (and passed) this subject called physics, and noted along the way that there are many seemingly impossible things that are indeed possible given the right information.


What makes you think it does make a difference? Feel? I just can't see how it would matter. When you loft thr front wheel, you're pivoting the bike around the rear hub (and, to a lesser extent, whatever pivot point your rear suspension might have.) To make things simple, let's just talk about a hardtail. When you pull up on the bar to loft the front wheel, you're using the bike as a lever. The handlebar is where the force is applied, and the center of the rear wheel is the fulcrum. The shape of the lever dosn't really matter, so long as the fulcrum, the load, and point where the force is applied are in the same place relative to each other.


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## gil_caz (Jul 12, 2006)

Hardtails Are Better said:


> What makes you think it does make a difference? Feel? I just can't see how it would matter. When you loft thr front wheel, you're pivoting the bike around the rear hub (and, to a lesser extent, whatever pivot point your rear suspension might have.) To make things simple, let's just talk about a hardtail. When you pull up on the bar to loft the front wheel, you're using the bike as a lever. The handlebar is where the force is applied, and the center of the rear wheel is the fulcrum. The shape of the lever dosn't really matter, so long as the fulcrum, the load, and point where the force is applied are in the same place relative to each other.


WORD!!!


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## Huck Banzai (May 8, 2005)

The shape of a lever doesnt make a difference?

Exiting...


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## XSL_WiLL (Nov 2, 2004)

The change in weight distribution would be fairly minimal. Where the stem clamps the steer tube doesn't really affect handling (assuming bar position is the same). It's more the leverage that it exerts on the steer tube. If you clamp it high up, it has more leverage, down low, less leverage.

The way he's describing the lever (with the fulcrum, the load, and point where the force is applied in the same place relative to each other) makes sense. I think the comment about the shape of the lever is being misunderstood.

Look at the new Santa Cruz DJ bike. The guys had to use a huge stack of spacers AND high rise bars to get the bar where it was before because the headtube is so much shorter.


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## Hardtails Are Better (May 4, 2005)

Huck Banzai said:


> The shape of a lever doesnt make a difference?
> 
> Exiting...


I don't think you took that the right way. I meant somthing like this:

(ignoring that my picture sucks, and pretending that they're the same length, and that the fulcrum is in the middle of both, and that the fulcrum is colinear with both ends in the second one)


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## presslab (Jan 5, 2007)

Remember when they had those "offset" cranks. I LOL'd when I saw those.


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## Hardtails Are Better (May 4, 2005)

presslab said:


> Remember when they had those "offset" cranks. I LOL'd when I saw those.


That's exactly what I'm talking about. That's the same goddamn thing as a regular crank arm in terms of function, assuming that the non drive side arm is offest the other direction, so that the pedal threads and spindle are all colinear.


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## lelebebbel (Jan 31, 2005)




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## dusthuffer (Nov 30, 2006)

yes it changes the pivot point for "the lever" but when would you ever pivot the bike around that point? Doing wheelies, lifting up the front wheel for jumps, is pivoting around the rear axel as some people wrote. Maybe on some crazy dirt jump moved yet to be invented you would pivot the bike around the top of the head tube.


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## fonseca (Jan 12, 2004)

presslab said:


> Remember when they had those "offset" cranks. I LOL'd when I saw those.


I believe those were offset so that they could hollow the inside from each end for weight savings. Had nothing to do with leverage.

I can remember really wanting a set!


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## CrustyOne (Oct 29, 2007)

Huck Banzai said:


> Dont be quick to mske assertions with no foundation.I dont know HOW significant it is, but is most certainly not BS.
> 
> I used to take (and passed) this subject called physics, and noted along the way that there are many seemingly impossible things that are indeed possible given the right information.


Nah..it really is BS, your not taking the whole system into account, concentrating on a small offfset in isolation is misleading


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## .Danno. (Jun 18, 2005)

The bars, stem, steerer, crown and stanchions form a rigid body. If you could somehow connect the bars to the stanchions and still have the same hand positions as when the bar was attached to the steerer/stem the bike would ride the same. The only difference would be weight distribution.


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## 501 (Jan 27, 2007)

so sinse most of you disagree with this logic i will be back on to prove it to you when i have more time.

well if you believe that your hands being in the same spot has everything to do with it, then why does a bike with a 23" tt with a 50mm stem and one with 22" tt with a 100mm stem (both of these set ups at the same hieght) pull up easier? call me crazy but your hands are in the exact same place. would you disagree with this also?


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## .Danno. (Jun 18, 2005)

501 said:


> so sinse most of you disagree with this logic i will be back on to prove it to you when i have more time.
> 
> well if you believe that your hands being in the same spot has everything to do with it, then why does a bike with a 23" tt with a 50mm stem and one with 22" tt with a 100mm stem (both of these set ups at the same hieght) pull up easier? call me crazy but your hands are in the exact same place. would you disagree with this also?


That would feel totally different for several reasons because the front wheel isn't in the same position.


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## CrustyOne (Oct 29, 2007)

501 said:


> so sinse most of you disagree with this logic i will be back on to prove it to you when i have more time.
> 
> well if you believe that your hands being in the same spot has everything to do with it, then why does a bike with a 23" tt with a 50mm stem and one with 22" tt with a 100mm stem (both of these set ups at the same hieght) pull up easier? call me crazy but your hands are in the exact same place. would you disagree with this also?


Yep disagree
EVERYTHING ELSE BEING EQUAL (including weight distribution/centre of mass)...it will present the same moment about the rear axle and lift the same


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## Djponee (Dec 20, 2006)

> If your bar is in the exact same place, regardless of how it is achieved (bar or spacers), I don't see how the handling would be any different.


unless the bars have different sweep, then it would be different.


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## Hardtails Are Better (May 4, 2005)

501 said:


> so sinse most of you disagree with this logic i will be back on to prove it to you when i have more time.
> 
> well if you believe that your hands being in the same spot has everything to do with it, then why does a bike with a 23" tt with a 50mm stem and one with 22" tt with a 100mm stem (both of these set ups at the same hieght) pull up easier? call me crazy but your hands are in the exact same place. would you disagree with this also?


That's different, because, as others said, your weight distribution is different. The longer stem puts your weight over the front wheel more, thus making it more difficult to loft the front end.


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## CrustyOne (Oct 29, 2007)

Yea..I think thats what he is going on about....the other factors that change when you go from one scenario to the next......its got nothing to do with the leverage point which he implied in the original post ....leverage point is not changing


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## Boulder Pilot (Jan 23, 2004)

*What was the question?*

To answer the question, unless requested, don't change the constants. My take on this subject is that the frame, fork, and stem are constant. The handlebar is the variable, but only the rise, not sweep. 1" handlebar rise plus 1" spacer = 2" rise. 2" handlebar rise plus no spacer = 2" rise.
If you want to bring top tube length and stem length into a discussion about where your grips are going to end up in space, please start a new thread.


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## sleeymas (May 19, 2007)

i might be going at this wrong but bars are shaped with a drop in the middle with riser bars right? so your hands are pulling at the same height in both scenarios. the issue i have is in one the stem is higher than the other and the stem is the actual point where force is put on the frame now where your hands pull. i may be way off but i am thinking but in one scenario your force is actually applied to the frame on inch lower or 2 inches lower depending on how much rise you use???????? no physics major here just staring at my 2 sets of bars and how the force looks like it would transfer, i may be way off


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## Hardtails Are Better (May 4, 2005)

sleeymas said:


> i might be going at this wrong but bars are shaped with a drop in the middle with riser bars right? so your hands are pulling at the same height in both scenarios. the issue i have is in one the stem is higher than the other and the stem is the actual point where force is put on the frame now where your hands pull. i may be way off but i am thinking but in one scenario your force is actually applied to the frame on inch lower or 2 inches lower depending on how much rise you use???????? no physics major here just staring at my 2 sets of bars and how the force looks like it would transfer, i may be way off


Look at it this way. Regardless of where the stem is, the force of you pulling up on the bars is going to get transfered to the frame via the headset. Stem position is irrelevant.


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## powderho (Jan 14, 2004)

sleeymas said:


> i might be going at this wrong but bars are shaped with a drop in the middle with riser bars right? so your hands are pulling at the same height in both scenarios. the issue i have is in one the stem is higher than the other and the stem is the actual point where force is put on the frame now where your hands pull. i may be way off but i am thinking but in one scenario your force is actually applied to the frame on inch lower or 2 inches lower depending on how much rise you use???????? no physics major here just staring at my 2 sets of bars and how the force looks like it would transfer, i may be way off


I'll buy into this line of reasoning. The force is applied to the frame at the spot where the stem clamps down on the handlebars, right? So handlebars with more rise will put more force on that location than bars with a lower rise (assuming the same force is applied). The higher-rise bars provide an increase in leverage to that spot. Work/power/moment=force * distance.


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## sleeymas (May 19, 2007)

yeah no physics degree here but the force goes bar, down the bar into the stem from the stem to the steerer tube then to headset then to frame. so if stem is higher on steerer tube then the force is being applied higher on tube thus creating a lever point just slightly different. thats how i see it atleast. i just know when i tried doing it both ways since i had the stuff laying around it felt differnt.


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## Hardtails Are Better (May 4, 2005)

sleeymas said:


> yeah no physics degree here but the force goes bar, down the bar into the stem from the stem to the steerer tube then to headset then to frame. so if stem is higher on steerer tube then the force is being applied higher on tube thus creating a lever point just slightly different. thats how i see it atleast. i just know when i tried doing it both ways since i had the stuff laying around it felt differnt.


The bit about a lever dosn't make sense, because, at least in theroy, none of those parts are moving relative to each other. They're effecively one piece, in terms of how they act on the rear wheel. Obviously the headset turns, but that's in an entirely different direction. Everything else is bolted together, and as such is effectively rigid.


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## sleeymas (May 19, 2007)

maybe lever isnt best way to say it, i mean the point at which you are applying force is lower when you use a higher rise bar, since you are transfering power to the middle of the bar down to the stem. i may be way off base just what i noticed while sitting here tinkering with my bars and it feels differnt so there must be something.


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## Hardtails Are Better (May 4, 2005)

sleeymas said:


> maybe lever isnt best way to say it, i mean the point at which you are applying force is lower when you use a higher rise bar, since you are transfering power to the middle of the bar down to the stem. i may be way off base just what i noticed while sitting here tinkering with my bars and it feels differnt so there must be something.


How are you experimenting? I bet there's some other factor involved.

The bit about where you apply the force is irrelevant, for the reasons I've already stated. You're looking at too small a system. Once you consider the entire bike, it dosn't matter.


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## sleeymas (May 19, 2007)

like i said im probably wrong, i have no physics degree, i was just throwing it out there because it was bothering me and i was looking for someone to come up with mathmatical evidence to set my mind right. i would love to see a force gauge on the steer tube to see if force is different. i am thinking of this from a wheelie stand point by the way. and variable wise maybe one set of bars has more flex due to design, i would think a flat bar is different than a riser, i know i should not think like that but in real life there are issues. dunno call me crazy i just dont see it and nothing i have read has made me go you know what im way off base. but all in all what does it really matter, i picked my stack and my bars because it feels best to me. and to me i feel that i have more control with a lower stack and higher bars than with high stack and low bars, it might all be in my mind. not argueing just confused and now interested in an answer. thanks for making me think hardtail im never gonna get to sleep tonight now


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## 501 (Jan 27, 2007)

sleeymas said:


> yeah no physics degree here but the force goes bar, down the bar into the stem from the stem to the steerer tube then to headset then to frame. so if stem is higher on steerer tube then the force is being applied higher on tube thus creating a lever point just slightly different. thats how i see it atleast. i just know when i tried doing it both ways since i had the stuff laying around it felt differnt.


here we go this is what i am talking about. my other example wasnt the best way to try to explain since your wieght does change.

now lets imagine a line drawn from the stem to the rear axle with a low stack hieght the line would be lower than if you have a tall stack hieght right? this is where your leverage point changes. the lower that imaginary line is the less effort required to pull up.

if this still doesnt make since, you just have to try it yourself and you will see

i am done:madman:


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## Boulder Pilot (Jan 23, 2004)

*Not that anyone cares*

After plotting this 2" rise vs 1" rise plus 1" spacer, I can see where the "easier leverage"
camp basis their argument. After exaggerating the numbers(4"rise vs 1" rise plus 3" spacer) their argument becomes clearer(for myself). I still am in Hardtails camp though,because the 1" of stem heigth difference seems insignificant(to me).


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## CrustyOne (Oct 29, 2007)

Hardtails Are Better said:


> Look at it this way. Regardless of where the stem is, the force of you pulling up on the bars is going to get transfered to the frame via the headset. Stem position is irrelevant.


AArgh..thats complete bollox.......im outta here:madman:


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## .Danno. (Jun 18, 2005)

501 said:


> here we go this is what i am talking about. my other example wasnt the best way to try to explain since your wieght does change.
> 
> now lets imagine a line drawn from the stem to the rear axle with a low stack hieght the line would be lower than if you have a tall stack hieght right? this is where your leverage point changes. the lower that imaginary line is the less effort required to pull up.
> 
> ...


Just look at four points of force - two hand contacts, upper headset race, and lower headset race. If the bars are in the same position and you're pulling with the same force, the forces at the headset will be the same regardless of how you connect things together because it's a rigid body.

I can see how if you haven't taken engineering courses like 'statics' that this would be confusing though.

I'm done too.


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## be350ka (Dec 17, 2004)

njhcx4xlife said:


> The handling may be exactly the same when turning since your hands are in the same spot at the end result but the point in which the stem attached to the steerer tube and weight distribution has to have an effect on the leverage.


Exactly!! I think the general rule of thumb for a 1 1/8" steerer is 40mm of spacers (max). There have been many cases of headsets creaking (kings) with the new crop of longer travel single crown forks and I have experienced it personally. In addition, a riding buddy of mine has a King and when he switches out his stem and changes his spacer stack (inc) he all of a sudden starts creaking. Is it a function of leverage? I tend to think that the longer the leverage arm is, the more force you put on the headset.

As far as handling, I wouldn't think that it makes a big difference. Unless you have so many spacers that you are damaging the integrity of the frame.


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## sleeymas (May 19, 2007)

ic, so what your telling me is no force is transfered through the stem and steerer tube. look at them as they are non existent. so if built a small scale model and say did 3 or 4 inches of rise to take it an extreme that there would be no difference. i am asking because i always wanted to be an engineer but bills and family and a high paying job keep me from going back to school. so this stuff interests me. what if you are pulling strait back like you do when you are flywing off a drop?? same principle or do points change then???


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## .Danno. (Jun 18, 2005)

sleeymas said:


> ic, so what your telling me is no force is transfered through the stem and steerer tube. look at them as they are non existent. so if built a small scale model and say did 3 or 4 inches of rise to take it an extreme that there would be no difference. i am asking because i always wanted to be an engineer but bills and family and a high paying job keep me from going back to school. so this stuff interests me. what if you are pulling strait back like you do when you are flywing off a drop?? same principle or do points change then???


Yeah, think of them as non-existent because you assume that it's just one piece that doesn't bend - rigid. You could have a steerer tube 10 feet high with a stem that drops back down 10 feet and as long as the bar is in the same place it'll feel the same (not counting the weight of all that stuff). Internally the bar/stem forces will be different, but if nothing is bending it'll be the same to the rider.


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