# Demo 9 Suspension path . . .



## RedDwarf (Mar 2, 2004)

If you notice that the "outside" link moves back at the top . . . almost acting like a floating brake arm . . . hum, cool.


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## Tracerboy (Oct 13, 2002)

DJBiker said:


> If you notice that the "outside" link moves back at the top . . . almost acting like a floating brake arm . . . hum, cool.


im getting hypmotized stairing at it.


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## .WestCoastHucker. (Jan 14, 2004)

DJBiker said:


> If you notice that the "outside" link moves back at the top . . . almost acting like a floating brake arm . . . hum, cool.


isn't that typical of a Horst Link?


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## RED5 (Jan 4, 2004)

*And...*

that is why some, myself included, would argue that a Horst Link bike doesn't need a floater. And that is all I'm going to say about that.


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## 006_007 (Jan 12, 2004)

.WestCoastHucker. said:


> isn't that typical of a Horst Link?


Ding ding ding ding ding, send this man to the head of the class!


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## Skygrounder (Apr 26, 2004)

okay that was driving me completely frickin nuts....here's a non-seizure-inducing version:

(edit: btw, thanks for posting that, DJBiker, very cool)


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## .WestCoastHucker. (Jan 14, 2004)

Skygrounder said:


> okay that was driving me completely frickin nuts....here's a non-seizure-inducing version


yeah, but who rides that slow.....


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## Lucky13 (Jan 14, 2004)

I no get this crap: from the animation it looks like the rear axel's path is vertical. But how could that be if it pivots on the point right next to bb?

Thanks!


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## .WestCoastHucker. (Jan 14, 2004)

because the dropout isn't on the chainstay......
and i see a rearward path, not vertical.....


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## Lucky13 (Jan 14, 2004)

Ah, got it, thanks man!


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## B_LOWrider#1.5 (Nov 7, 2004)

*a*

But i wish it was like this http://www.pinkbike.com/modules/photo/?op=view&image=350742


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## Mike627 (Jul 2, 2004)

Lucky13 said:


> I no get this crap: from the animation it looks like the rear axel's path is vertical. But how could that be if it pivots on the point right next to bb?
> 
> Thanks!


Because there are two [major] pivot points, its actually closer to elliptical than anything. because the axle is between both of the pivots (or close to it) the section of ellipse that makes up the path is very close to flat.


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## SHIVER ME TIMBERS (Jan 12, 2004)

seizure are cool


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## BJ- (Jan 28, 2004)

so is it accurate...

becuase if it is then thats a really well enginered wheel path...very vertical...

and no i wont rant on about how ill have mine soon...oh woops...to late...


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## WheelieMan (Jan 19, 2004)

BJ- said:


> so is it accurate...
> 
> becuase if it is then thats a really well enginered wheel path...very vertical...
> 
> and no i wont rant on about how ill have mine soon...oh woops...to late...


And no, the demo does not have a vertical or rearward wheelpath. It is actually a forward arching wheelpath like most FSRs.


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## BJ- (Jan 28, 2004)

WheelieMan said:


> And no, the demo does not have a vertical or rearward wheelpath. It is actually a forward arching wheelpath like most FSRs.


silly me...thats just the geometry pic being edited...

(laughing)

now i see why some people think im a little slow...



006_007 said:


> Ding ding ding ding ding, send this man to the head of the class!


id sure as hell like to think he was if was still at school...seems as hes like 30 summin...


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## j6105 (Apr 10, 2004)

*really*

hey,
Wheelieman is full of crap. I have been in the specialized factory development room w/ a demo 9 prototype frame and production demo 9 without a shock mounted. Guy that designed it, Jason Chamberlain, showed me the vertical axle path. Moves about 1mm so technically not 100% vertical, but i would call it vertical for sure. Darn people like wheelieman who make crap up with their limited minds since they are jealous(we all secretly wish we were BJ~). Ask me questions, ill prove im not FOS


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## RED5 (Jan 4, 2004)

*Hey j*



j6105 said:


> hey,
> Wheelieman is full of crap. I have been in the specialized factory development room w/ a demo 9 prototype frame and production demo 9 without a shock mounted. Guy that designed it, Jason Chamberlain, showed me the vertical axle path. Moves about 1mm so technically not 100% vertical, but i would call it vertical for sure. Darn people like wheelieman who make crap up with their limited minds since they are jealous(we all secretly wish we were BJ~). Ask me questions, ill prove im not FOS


 so would you say the Big Hit would follow the same sort of path and only move off the vertical 1mm? I've seen similiar test from Specialized and had people on this board tell me different using programs to detail the axle path.


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## WheelieMan (Jan 19, 2004)

j6105 said:


> hey,
> Wheelieman is full of crap. I have been in the specialized factory development room w/ a demo 9 prototype frame and production demo 9 without a shock mounted. Guy that designed it, Jason Chamberlain, showed me the vertical axle path. Moves about 1mm so technically not 100% vertical, but i would call it vertical for sure. Darn people like wheelieman who make crap up with their limited minds since they are jealous(we all secretly wish we were BJ~). Ask me questions, ill prove im not FOS


Please explain to me how I am full of crap, I would enjoy hearing some reasoning.


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## Skygrounder (Apr 26, 2004)

.WestCoastHucker. said:


> yeah, but who rides that slow.....


 Well I heard the Demo9 was becoming all the rave amongst the rails-to-trails set...


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## Skygrounder (Apr 26, 2004)

j6105, Go play around over at nine-honking-inches-of-travel.com and you can see the axle path. Here's a superimposed image of static vs. full compression, the axle is definitely moving forward quite a bit.

(I swear I'm done playing with Photoshop for this thread)


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## RED5 (Jan 4, 2004)

*Problem...*



Skygrounder said:


> j6105, Go play around over at nine-honking-inches-of-travel.com and you can see the axle path. Here's a superimposed image of static vs. full compression, the axle is definitely moving forward quite a bit.
> 
> (I swear I'm done playing with Photoshop for this thread)


 I could be wrong, but by the looks of the front wheel the whole bike seems to have moved/rolled back when it compressed. Don't get me wrong I'm not debating the axle path, just saying that this pic looks inconclusive.


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## WheelieMan (Jan 19, 2004)

red5 said:


> I could be wrong, but by the looks of the front wheel the whole bike seems to have moved/rolled back when it compressed. Don't get me wrong I'm not debating the axle path, just saying that this pic looks inconclusive.


Yeah thats deffinatley not very accurate. Im sure that the person who created that animation was not concerned with making it accurate.

Here is the demo that I put in the linkage program, also not accurate, but at least its something to look at.


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## Skygrounder (Apr 26, 2004)

red5 said:


> I could be wrong, but by the looks of the front wheel the whole bike seems to have moved/rolled back when it compressed. Don't get me wrong I'm not debating the axle path, just saying that this pic looks inconclusive.


 Yeah I agree, the bike does seem to have rolled back a bit. I aligned the superimposed images based on the rocks at the bottom. Measuring on the zoomed-in superimposed image the gold fork adjuster caps seem to have moved to the left (back) two pixels at full compression. The axle moves forward (to the right) 10 pixels though at full compression.

I measured the outside diameter of BigDigger's huge-a$$ Roller 2.6 tires and they were actually 27" (i.e., not 26") tall...so dividing by their height on the image you get 5.62 pixels/inch. The wheel moving forward 8 pixels (or about an inch and a half).

Of course this is all inexact...perhaps the web designer who made nine-honking-inches-of-travel.com used a bit of "creative license" on the thing...but obviously taking measurements from such a Flash movie is the farthest thing from science


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## Skygrounder (Apr 26, 2004)

WheelieMan said:


> Yeah thats deffinatley not very accurate. Im sure that the person who created that animation was not concerned with making it accurate.
> 
> Here is the demo that I put in the linkage program, also not accurate, but at least its something to look at.


 Very cool...what program is that?....I think I could waste a hell of a lot of time with that!


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## RED5 (Jan 4, 2004)

*Yep...*



WheelieMan said:


> Yeah thats deffinatley not very accurate. Im sure that the person who created that animation was not concerned with making it accurate.
> 
> Here is the demo that I put in the linkage program, also not accurate, but at least its something to look at.


 that looks very similiar to the program that was used to argue against my point about the Big Hit having a near vertical axle path, huh Zedro.


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## WheelieMan (Jan 19, 2004)

Skygrounder said:


> Very cool...what program is that?....I think I could waste a hell of a lot of time with that!


Its a great program, I have put every possible frame that I know of into it and is a great tool to compare geometry curves, chain growth, wheelpaths etc. And its also fun to watch how the suspensions work, you can animate them as well. The name of it is Linkage Program and I found it over at ridemonkey a while back, might want to do a search for it!


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## j6105 (Apr 10, 2004)

*hey*

hey,
jack*** wheelie man. Congrats you just modeled a demo 9 like a single pivot. You forgot the other two bars are there for a reason, i don't know why the hell you people think modeling software will prove me wrong when i have seen it on the specialized computers and in REAL LIFE. Your just guessing, i have seen concrete evidence. Yes i have modeling software, solidworks 2004 to be precise, but please don't act like an idiot and ruin the image of real bike designers. Go home.


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## WheelieMan (Jan 19, 2004)

j6105 said:


> hey,
> jack*** wheelie man. Congrats you just modeled a demo 9 like a single pivot. You forgot the other two bars are there for a reason, i don't know why the hell you people think modeling software will prove me wrong when i have seen it on the specialized computers and in REAL LIFE. Your just guessing, i have seen concrete evidence. Yes i have modeling software, solidworks 2004 to be precise, but please don't act like an idiot and ruin the image of real bike designers. Go home.


I dont know about you but I see 4 pivots on there, its not a single pivot at all.


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## WheelieMan (Jan 19, 2004)

Under full compression:


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## biker3 (Jan 18, 2004)

j6105 said:


> hey,
> jack*** wheelie man. Congrats you just modeled a demo 9 like a single pivot. You forgot the other two bars are there for a reason, i don't know why the hell you people think modeling software will prove me wrong when i have seen it on the specialized computers and in REAL LIFE. Your just guessing, i have seen concrete evidence. Yes i have modeling software, solidworks 2004 to be precise, but please don't act like an idiot and ruin the image of real bike designers. Go home.


J your retarted. You just explained your retartedness by saying you listened to specialized. Its like WTF do you think they're going to tell you? Ovcourse they are going to say its vertical its just specialized propaganda about how they have "the best FSR" blah blah. There are actually A LOT of people who have some not so hot things to say about specialized's FSR. Your just got proved wrong by a diagram so STFU and dont talk crap about my homey wheelieman. The kid knows his stuff. Just cause ur a dealer doesn't mean everything they tell you is true. The demo DOES not have a fully vertical wheelpath ive seen it in real life as well and on the nine honking site. Any non-autistic person can see the real wheelpath.


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## Skygrounder (Apr 26, 2004)

j6105 said:


> hey,
> jack*** wheelie man. Congrats you just modeled a demo 9 like a single pivot. You forgot the other two bars are there for a reason, i don't know why the hell you people think modeling software will prove me wrong when i have seen it on the specialized computers and in REAL LIFE. Your just guessing, i have seen concrete evidence. Yes i have modeling software, solidworks 2004 to be precise, but please don't act like an idiot and ruin the image of real bike designers. Go home.


 Is it me or are you the only one calling people names here? Even after two personal attacks, I've yet to hear wheelie man return fire. I don't know if you too had some bad blood somewhere else, but I'll tell you that from my point of view I tend to take the opinions of people who attack with a grain of salt. I don't think anyone here is arguing as to whether or not the Demo9 is a good bike or not...I imagine most here are only trying to learn about suspension design as I am. (And for the record, I've poked fun at Demo9's myself in the past, but only because my brother owns one, and it's fun to give him hell about it even though in the dozen DH runs I've done on it I'm extremely impressed with it).

I would also argue that a good computer model in this case is far more accurate than the naked eye. I would NOT however argue that the computer model (if you can even call it that) I've shown is worth a damn as far as drawing a hard conclusion for the obvious reasons. I know nothing about WheelieMan's model so I can't speak for it either.

Question for you though when you saw the demo9 function in the Spec. factory...was only the spring removed or was the entire rear shock removed?


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## TheSherpa (Jan 15, 2004)

biker3 said:


> J your retarted. You just explained your retartedness by saying you listened to specialized. Its like WTF do you think they're going to tell you? Ovcourse they are going to say its vertical its just specialized propaganda about how they have "the best FSR" blah blah. There are actually A LOT of people who have some not so hot things to say about specialized's FSR. Your just got proved wrong by a diagram so STFU and dont talk crap about my homey wheelieman. The kid knows his stuff. Just cause ur a dealer doesn't mean everything they tell you is true. The demo DOES not have a fully vertical wheelpath ive seen it in real life as well and on the nine honking site. Any non-autistic person can see the real wheelpath.


I would have to agree fully. Specialed is all about shitty propaganda and lieing to the uniformed public. But, they still make badass bikes.

-TS


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## konabiker (Jan 19, 2004)

biker3 said:


> J your retarted. You just explained your retartedness by saying you listened to specialized. Its like WTF do you think they're going to tell you? Ovcourse they are going to say its vertical its just specialized propaganda about how they have "the best FSR" blah blah. There are actually A LOT of people who have some not so hot things to say about specialized's FSR. Your just got proved wrong by a diagram so STFU and dont talk crap about my homey wheelieman. The kid knows his stuff. Just cause ur a dealer doesn't mean everything they tell you is true. The demo DOES not have a fully vertical wheelpath ive seen it in real life as well and on the nine honking site. Any non-autistic person can see the real wheelpath.


totally off topic but, are you getting a dildo8?


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## j6105 (Apr 10, 2004)

*igit*

did i say i listened to specialized propaganda dip? did i say i looked it up online? NO. Did i say i went inside the specialized top secret develpment headquarters in morgan hill california? YES. Did i say i measured the axle path of two bikes(prototype and production) to see if the wheelpath was vertical? YES. Did i talk to jason chamberlain, the man that made the bike? YES. Once again did i do this all in real life? YES. now i know that skygrounder and biker3 are also dip s**** that will go with someones opinion just because it looks pretty. how sad. anyway im going to do something you probably hardly get too, bike, so i will be back at ~ 6 to defend my case from you morons.


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## Skygrounder (Apr 26, 2004)

One more thing...just looking at the design of the Demo9...I just realized that it in fact cannot be any more vertical than a single pivot...here's why:

First take a look at the lower chainstay triangle (the one the shock is mounted to), this piece functions as a single pivot. If, hypothetically, you had a bike with the same configuration as a Demo9 but with the wheel attached to this triangle (and all of the other linkage were removed), you would have a traditional single pivot bike.

Now, realize that at static (unweighted) height, the lower bar of this triangle is essentially parallel with the longitudinal axis of the bike, i.e. it runs directly fore/aft, parallel to the ground.

The rear pivot point of this lower chainstay triangle will travel in an upward and very slightly forward arc when the suspension is loaded.

Now then, look at where the wheel attaches to the upper chainstay triangle. The relationship between the wheel axle and the aft pivot point of lower chainstay triangle is also essentially parallel with the longitudinal axis of the bike at static height. It being at such an angle, there is absolutely no way that it can compensate for the forward movement of the lower chainstay triangle as it swings in an upward arc.

Looking at this another way, the bike's wheelbase (and/or BB to axle distance) is AS LONG AS IT CAN POSSIBLY BE at static ride height. Thus when the lower chainstay triangle swings up and decreases the distance between the BB and its aft pivot, the wheel must travel forward (toward the BB of the bike).


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## TheSherpa (Jan 15, 2004)

j6105 said:


> did i say i listened to specialized propaganda dip? did i say i looked it up online? NO. Did i say i went inside the specialized top secret develpment headquarters in morgan hill california? YES. Did i say i measured the axle path of two bikes(prototype and production) to see if the wheelpath was vertical? YES. Did i talk to jason chamberlain, the man that made the bike? YES. Once again did i do this all in real life? YES. now i know that skygrounder and biker3 are also dip s**** that will go with someones opinion just because it looks pretty. how sad. anyway im going to do something you probably hardly get too, bike, so i will be back at ~ 6 to defend my case from you morons.


Hahahahahah, your so full of sh!t it's coming out of your eyes. Tell Jason Chamberlain he is full of SH!T as well. I would love to see him come on the boards and defend himself.

-TS


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## BigDigger (Mar 29, 2004)

j6105 said:


> did i say i listened to specialized propaganda dip? did i say i looked it up online? NO. Did i say i went inside the specialized top secret develpment headquarters in morgan hill california? YES. Did i say i measured the axle path of two bikes(prototype and production) to see if the wheelpath was vertical? YES. Did i talk to jason chamberlain, the man that made the bike? YES. Once again did i do this all in real life? YES. now i know that skygrounder and biker3 are also dip s**** that will go with someones opinion just because it looks pretty. how sad. anyway im going to do something you probably hardly get too, bike, so i will be back at ~ 6 to defend my case from you morons.


My goodness, what an angry little man you are. Instead of going out and riding your bike, perhaps you should consider taking a nap.

Seriously, whether the axel path is a straight line, an arc, or a fvcking figure eight, if you don't calm down, you're going to end up with a bad case of hemehheroids  . And then you'll be sorry. Very sorry.

Oh, and by the way, the Demo 9 axel path is curved. How do I know this? Well, I went to the Specialized super-duper top secret development headquarters (which is significantly more top secret than the top secret morgan hill facility which is really only sorta top secret) and the location of which is so secret I would spontaneously combust if I were to mention its location (I can, however, reveal that it is burried beneath a mountain and impervious to nuclear attack). Whilst there I measured the axel path of FOUR bikes, using lasers, talked to Jason Chamberlain AND his parents, the Pope, Osama Bin Laden, and Elvis Presley. ALL confirmed that the axel path was curved.


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## konabiker (Jan 19, 2004)

BigDigger said:


> My goodness, what an angry little man you are. Instead of going out and riding your bike, perhaps you should consider taking a nap.
> 
> Seriously, whether the axel path is a straight line, an arc, or a fvcking figure eight, if you don't calm down, you're going to end up with a bad case of hemehheroids  . And then you'll be sorry. Very sorry.
> 
> Oh, and by the way, the Demo 9 axel path is curved. How do I know this? Well, I went to the Specialized super-duper top secret development headquarters (which is significantly more top secret than the top secret morgan hill facility which is really only sorta top secret) and the location of which is so secret I would spontaneously combust if I were to mention its location (I can, however, reveal that it is burried beneath a mountain and impervious to nuclear attack). Whilst there I measured the axel path of FOUR bikes, using lasers, talked to Jason Chamberlain AND his parents, the Pope, Osama Bin Laden, and Elvis Presley. ALL confirmed that the axel path was curved.


Church, Church


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## The Kadvang (Jul 25, 2004)

BigDigger said:


> My goodness, what an angry little man you are. Instead of going out and riding your bike, perhaps you should consider taking a nap.
> 
> Seriously, whether the axel path is a straight line, an arc, or a fvcking figure eight, if you don't calm down, you're going to end up with a bad case of hemehheroids  . And then you'll be sorry. Very sorry.
> 
> Oh, and by the way, the Demo 9 axel path is curved. How do I know this? Well, I went to the Specialized super-duper top secret development headquarters (which is significantly more top secret than the top secret morgan hill facility which is really only sorta top secret) and the location of which is so secret I would spontaneously combust if I were to mention its location (I can, however, reveal that it is burried beneath a mountain and impervious to nuclear attack). Whilst there I measured the axel path of FOUR bikes, using lasers, talked to Jason Chamberlain AND his parents, the Pope, Osama Bin Laden, and Elvis Presley. ALL confirmed that the axel path was curved.


Big Digger is right, because I was there too... that axel path was damn CURVY


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## Jm. (Jan 12, 2004)

j6105 said:


> hey,
> Wheelieman is full of crap. I have been in the specialized factory development room w/ a demo 9 prototype frame and production demo 9 without a shock mounted. Guy that designed it, Jason Chamberlain, showed me the vertical axle path. Moves about 1mm so technically not 100% vertical, but i would call it vertical for sure. Darn people like wheelieman who make crap up with their limited minds since they are jealous(we all secretly wish we were BJ~). Ask me questions, ill prove im not FOS


Haha, one apple fell a little far from the tree.

No one really wants a vertical wheelpath. While it sounds great on paper, you have to consider that the further you go into travel the more pedal feedback you'll get due to more chain-tension being induced from the extending bb-to-axle (virtual chainstay) length.


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## Jm. (Jan 12, 2004)

Skygrounder said:


> One more thing...just looking at the design of the Demo9...I just realized that it in fact cannot be any more vertical than a single pivot...here's why:
> 
> First take a look at the lower chainstay triangle (the one the shock is mounted to), this piece functions as a single pivot. If, hypothetically, you had a bike with the same configuration as a Demo9 but with the wheel attached to this triangle (and all of the other linkage were removed), you would have a traditional single pivot bike.
> 
> ...


Yes yes, but that's what they'd be expecting us to think!

In other words, that makes too much sense!

(yes, FSRs have an arcing wheelpath).


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## j6105 (Apr 10, 2004)

*hey,*

yes,
I must be bipolar like zedro  . Im just sick o people bagging on specialized when they gots no reason. My final word is the axle path is vertical. sorry all, im letting this one die because i now realize i will never win and will loose my rep. if i continue. ahh the tragedy.(i just got insulted by a vpp weilding, 16 year old hic from arkansas, ouch)

P.S. just in case zedro is reading this~~ the mavic 823's will be unchanged for 2005, website just updated. viva la michelin tubeless.


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## TheSherpa (Jan 15, 2004)

j6105 said:


> (i just got insulted by a vpp weilding, 16 year old hic from arkansas, ouch)


Damn, too bad that hick understands common physics and why you don't want a vertical suspension path.

-TS


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## shock (Aug 9, 2004)

*But the point I was trying to make in other threads about this*



red5 said:


> that is why some, myself included, would argue that a Horst Link bike doesn't need a floater. And that is all I'm going to say about that.


Is that, regardless of axle path, the axle and brake caliper are attached rigidly to the same piece of metal. No pivots in between the axle and the brake caliper. Their path is one and the same. With a floating brake, the caliper is NOT attached to the same piece of metal. This is the only way to remove the braking force from the suspension.


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## konabiker (Jan 19, 2004)

j6105 said:


> P.S. just in case zedro is reading this~~ the mavic 823's will be unchanged for 2005, website just updated. viva la michelin tubeless.


so the durability issues will still be there?

AwEsoME!!111!


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## RED5 (Jan 4, 2004)

*I'll bite...*



TheSherpa said:


> Damn, too bad that hick understands common physics and why you don't want a vertical suspension path.
> 
> -TS


 First let me say I'm serious when I ask this, I don't want to get involved in any of these debates I'm just curious...Why don't you want a vertical axle path? Thanks.


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## TheSherpa (Jan 15, 2004)

red5 said:


> First let me say I'm serious when I ask this, I don't want to get involved in any of these debates I'm just curious...Why don't you want a vertical axle path? Thanks.


Think of the massive chain growth you would have and lots of pedal feedback. I'm sure a "guru" can explain it a little better.

-TS


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## j6105 (Apr 10, 2004)

*no*

chain growth in not an issue i know that much. I have ridden 3 demos, including playin with an 8 but none of them have any adverse chainline effects. In FSR, The upper bar dips down, keeping the axle almost perfectly the same distance(i.e. no chainline growth). For example the lower bar cannot stretch can it? the wheel does not move forward during travel(like some vpp and single pivot), so in does not "load" the cogs w/ chain(rotate cassette backward), therefore when it extends again, the it no loaded chain to catch and create pedal feedback. In fact, if you have bighit or demo, run the deraillure so that it is fully extended in the largest cog becuase the compression of the suspension will not bend it further(on big hits the chainline actually shrinks like 1/2 inch). So equidistant + No forward wheel movement = same chainline = plush suspension = no brake jack = reason specialized has held onto FSR all these years.

P.S> the FSR on the demo is diff, Chamberlain calls it FSR plus or Super FSR. Check the Dirt mag review of the 04 demo 9 and i think he is quoted saying that in there too


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## BJ- (Jan 28, 2004)

i think its funny because...

some people were trying to argue that a diagram that isnt accurate is right...

(laughing)

even when the person who posted it said it wasnt accurate...

(laughing harder)

you guys...


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## singletrack (Feb 19, 2004)

*True Vertical Wheelpath*

Ok kids, anybody know what this is? Prolly before your time.

Wheel path is adjustable via seatstay angle 

And no comments on my dirty, dog-hair covered couch!


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## BJ- (Jan 28, 2004)

no i dont actually...

i know very little about the old days...what is it and whats it from...


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## shock (Aug 9, 2004)

*Wasn't that called the "shockster"?*



singletrack said:


> Ok kids, anybody know what this is? Prolly before your time.
> 
> Wheel path is adjustable via seatstay angle
> 
> And no comments on my dirty, dog-hair covered couch!


Bizarre, bolt on rear suspension for hardtails.....


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## lastminutebastrd (Jan 30, 2004)

singletrack said:


> Ok kids, anybody know what this is? Prolly before your time.
> 
> Wheel path is adjustable via seatstay angle
> 
> And no comments on my dirty, dog-hair covered couch!


ugh. I left my XC hardtail at work over the weekend a few years back, and when I came back my fellow mechanics thought it would be funny to bolt that to my bike.  I had to take it for a ride though.. hehe. Worst design ever, man was that thing flexy.


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## WheelieMan (Jan 19, 2004)

j6105 said:


> chain growth in not an issue i know that much. I have ridden 3 demos, including playin with an 8 but none of them have any adverse chainline effects. In FSR, The upper bar dips down, keeping the axle almost perfectly the same distance(i.e. no chainline growth). For example the lower bar cannot stretch can it? the wheel does not move forward during travel(like some vpp and single pivot), so in does not "load" the cogs w/ chain(rotate cassette backward), therefore when it extends again, the it no loaded chain to catch and create pedal feedback. In fact, if you have bighit or demo, run the deraillure so that it is fully extended in the largest cog becuase the compression of the suspension will not bend it further(on big hits the chainline actually shrinks like 1/2 inch). So equidistant + No forward wheel movement = same chainline = plush suspension = no brake jack = reason specialized has held onto FSR all these years.
> 
> P.S> the FSR on the demo is diff, Chamberlain calls it FSR plus or Super FSR. Check the Dirt mag review of the 04 demo 9 and i think he is quoted saying that in there too


You are contradicting yourself. If the demo has a vertical wheelpath like you claim, then it also will have significant chaingrowth. Theres no way around it


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## biker3 (Jan 18, 2004)

j6105 said:


> chain growth in not an issue i know that much. I have ridden 3 demos, including playin with an 8 but none of them have any adverse chainline effects. In FSR, The upper bar dips down, keeping the axle almost perfectly the same distance(i.e. no chainline growth). For example the lower bar cannot stretch can it? the wheel does not move forward during travel(like some vpp and single pivot),


total ******* here. At least I know what VPP is you moron. Last time I checked ALL Vpps have a rearward axle path. As well as the Single pivot on my gemini which has a REARWARD wheelpath. Im not going to say anything else because you obviously have no idea what your talking about. If you believe Josh Chamberlain wholy and entirely then your in for a RUDE awakening. Its like do you actually ****ing believe everything specialized tells you? Get out or here and go eat some rod lurker.


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## DHbiker (Apr 23, 2004)

Fun Program. Should say using 100mm or rear tavel.


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## j6105 (Apr 10, 2004)

*du*

ding ding ding! wheeliman just proved he is an unknowledgable. No chain growth b/c way upper bar moves and lower one can't stretch, no chain feedback because wheel does NOT move forward therefore NOT loading the cassette with the chain. Try reading wheelieman, it something even kis can do in the US, unless they fall off their bike too many times trying the world lamest and most purposeless trick (wheelies).


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## WheelieMan (Jan 19, 2004)

j6105 said:


> ding ding ding! wheeliman just proved he is an unknowledgable. No chain growth b/c way upper bar moves and lower one can't stretch, no chain feedback because wheel does NOT move forward therefore NOT loading the cassette with the chain. Try reading wheelieman, it something even kis can do in the US, unless they fall off their bike too many times trying the world lamest and most purposeless trick (wheelies).


I dont know why youre going into all this crap about "bars" it has nothing to do with that. Maybe you need a diagram, you are the ignorant one here.


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## WheelieMan (Jan 19, 2004)

If the demo had a vertical wheelpath like you claim, then distance B would be longer than distance A, its a fact. Thus, there would be chaingrowth.


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## singletrack (Feb 19, 2004)

lastminutebastrd said:


> ugh. I left my XC hardtail at work over the weekend a few years back, and when I came back my fellow mechanics thought it would be funny to bolt that to my bike.


 Hehe... My co-worker left his RM7 at the shop while his Super-T was in warranty (Destroyed in car related incident), on his day off I put a 95ish Judy XC (The yellow one) on it with 130mm high rise stem turned upside down.

Good thing he has a sense of humor.

I've got an pre-Pro-flex Offroad, rigid with flex stem and u-brake. I was thinking I'd put the shockster on there.... But the things never been used, I wouldn't want it to lose it's collectors value. It would be a good wine rack too. Too bad I don't drink wine. Lessin' it comes in a jug.


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## DHbiker (Apr 23, 2004)

Let's not argue. Lets all just download that program and play with it for hours trying to make some messed up frames instead of that.


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## Skygrounder (Apr 26, 2004)

"The Demo9 has a vertical axle path! We will welcome those who say otherwise with bullets and shoes."​


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## singletrack (Feb 19, 2004)

WheelieMan said:


> If the demo had a vertical wheelpath like you claim, then distance B would be longer than distance A, its a fact. Thus, there would be chaingrowth.


 You are modeling your example after a single pivot or non-horst 4bar....

I'm not agreeing with the other whacko though. True "Vertical" wheel path is not possible with pivots of any kind! Horst bikes are merely closer to vertical, and while the Demo looks different, it really works the same as any other horstie.

No, I'm not gonna draw a picture.


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## j6105 (Apr 10, 2004)

*ha*

wow,
ya wheelieman, model it right, the programs you are using don't have the potential to model the physics of parts moving together(use a 3d parts interface program) or guess what use this thing called real life, which you don't have. Guess i touched a raw bone w/ all the ignorants out there. i love my life  .

P.S. I realize nothing can be 100% vertical but it is dam close, singletrack the FSR is different because of the design, not because i think it looks different. Check the dirt mag issue with the 04 demo 9 review.


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## WheelieMan (Jan 19, 2004)

singletrack said:


> You are modeling your example after a single pivot or non-horst 4bar....
> 
> I'm not agreeing with the other whacko though. True "Vertical" wheel path is not possible with pivots of any kind! Horst bikes are merely closer to vertical, and while the Demo looks different, it really works the same as any other horstie.
> 
> No, I'm not gonna draw a picture.


Actually my picture is not describing any suspension design. All I am trying to point out, is that regardless of pivots, having a vertical wheelpath would cause chaingrowth. (Unless of course the bottom bracket was located 4.5 inches or more above the rear axle, but in the case of the demo9, its not)


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## WheelieMan (Jan 19, 2004)

j6105 said:


> wow,
> ya wheelieman, model it right, the programs you are using don't have the potential to model the physics of parts moving together(use a 3d parts interface program) or guess what use this thing called real life, which you don't have. Guess i touched a raw bone w/ all the ignorants out there. i love my life  .
> 
> P.S. I realize nothing can be 100% vertical but it is dam close, singletrack the FSR is different because of the design, not because i think it looks different. Check the dirt mag issue with the 04 demo 9 review.


You are complety dodging the truth here. My point can be illustrated equally well with microsoft paint, or some thousand dollar modeling program like one-space-designer.

Again, you are ignoring my point. I am not trying to say that the demo is a poor design, I am just pointing out the truth. The truth being that a design with a "vertical wheelpath" will have chaingrowth. (except for the condition stated in my previous post)


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## zedro (Jan 12, 2004)

i hope j6105 suddently doesnt decide he wants to design bikes, he may never get past the marketing brochure.


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## j6105 (Apr 10, 2004)

*que*

now,
i must insult zedro. who knew. block me or ruin my account punk but im callin u out. when the demo 8 comes in february i will post axle path with shock installed next to a T-square. With a chain on.


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## Shibby (Jan 13, 2004)

j6105 said:


> now,
> i must insult zedro. who knew. block me or ruin my account punk but im callin u out. when the demo 8 comes in february i will post axle path with shock installed next to a T-square. With a chain on.


 I am truely stupider for reading this thread. J6105, get help man.


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## zedro (Jan 12, 2004)

j6105 said:


> now,
> i must insult zedro. who knew. block me or ruin my account punk but im callin u out. when the demo 8 comes in february i will post axle path with shock installed next to a T-square. With a chain on.


 i will one(or five)-up your T-square with a CAD software output that can plot it to the 0.001mm. Give it up, you're out of your element....


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## Jm. (Jan 12, 2004)

Shibby said:


> I am truely stupider for reading this thread. J6105, get help man.


Yeah, I think I'm going to have to go stay in a Holiday Inn Express tonight.


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## singletrack (Feb 19, 2004)

Jm. said:


> Yeah, I think I'm going to have to go stay in a Holiday Inn Express tonight.


 Jm. wins the thread!


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## j6105 (Apr 10, 2004)

*a*

hmmm,
problem is you could never replicate the demo 9. You don't have any precise measurements and don;t have the knowledge; neither do i. you would hafta steal the file from specialized, or you could make a poor imatation like wheelieman, who knows after that bike you built......


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## SHIVER ME TIMBERS (Jan 12, 2004)

Friends friends can't we all get along...no throwing a Melt fit


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## j6105 (Apr 10, 2004)

also, 
wheelie man, at first you tell me the FSR suspension has an arching forward suspension line, and then that it has chain growth due to its vertical wheelpath. I sense a john kerry clone.


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## Shibby (Jan 13, 2004)

Nobody could ever match your wet-dream version of the Demo, with it's magical near-vertical wheelpath which mysteriously has no chain growth/



j6105 said:


> hmmm,
> problem is you could never replicate the demo 9. You don't have any precise measurements and don;t have the knowledge; neither do i. you would hafta steal the file from specialized, or you could make a poor imatation like wheelieman, who knows after that bike you built......


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## zedro (Jan 12, 2004)

j6105 said:


> hmmm,
> problem is you could never replicate the demo 9. You don't have any precise measurements and don;t have the knowledge; neither do i. you would hafta steal the file from specialized, or you could make a poor imatation like wheelieman, who knows after that bike you built......


 so if you have no information, and certainly no knowledge (no surprise there), why the hell are you flaping your lips in the first place?

no point in arguing with you really, you have no grasp of suspension concepts, nor have designed or analysed anything to form a knowledge base. This is like arguing with preschool kids...

PS, i reverse engineered suspension systems before to make modifications, you dont need 0.1mm's accuracy to recreate it. Not that anything that anyone else says would really matter to you. You musta really had a heavy crush on that Specialized guy to fight this hard for this one; your dreamy gaze probably kept your comprehension low...


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## WheelieMan (Jan 19, 2004)

j6105 said:


> also,
> wheelie man, at first you tell me the FSR suspension has an arching forward suspension line, and then that it has chain growth due to its vertical wheelpath. I sense a john kerry clone.


Thats why I put "vertical wheelpath" in quotes. Even *if* the demo9 had a vertical wheelpath (which it doesn't) it would still have chaingrowth.

Although I do agree that Kerry is a flip flopper!


----------



## j6105 (Apr 10, 2004)

nada my basis is from watching real life frames at the specialized headquarters. Wow i love this i shook the unshakable zedro, ha gave into temptation and insulted me. Just like the rest.


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## BigDigger (Mar 29, 2004)

Skygrounder said:


> "The Demo9 has a vertical axle path! We will welcome those who say otherwise with bullets and shoes."​


"Even people from another planet, if there were such people, would know that a Demo 9 has a vertical wheelpath, and no chaingrowth." "Also, there are no Demo 9's at the airport."


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## biker3 (Jan 18, 2004)

zedro said:


> so if you have no information, and certainly no knowledge (no surprise there), why the hell are you flaping your lips in the first place?
> 
> no point in arguing with you really, you have no grasp of suspension concepts, nor have designed or analysed anything to form a knowledge base. This is like arguing with preschool kids...
> 
> PS, i reverse engineered suspension systems before to make modifications, you dont need 0.1mm's accuracy to recreate it. Not that anything that anyone else says would really matter to you. You musta really had a heavy crush on that Specialized guy to fight this hard for this one; your dreamy gaze probably kept your comprehension low...


HAHAHA zedro owns any and all on MTBR. Except for Shredcommander and Huckworthypedophile, Whoever those two guys were they were hard as hel!


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## COmtbiker12 (Jan 12, 2004)

j6105 said:


> nada my basis is from watching real life frames at the specialized headquarters. Wow i love this i shook the unshakable zedro, ha gave into temptation and insulted me. Just like the rest.


 Dude....you're lame. The reason you think you saw it this way in real life is because you obviously could not physically see the EXACT way that the linkage works. Yea you can see a pretty good idea of hwo it works and such but when it comes to something such as wheelarc, there's so much going on that to the naked eye there is no way to actually see it. Listen to zedro, he's way smarter than you are and has a lot more experience with suspension designs in general. He built his own bike from the ground up after researching different suspension designs and weighing their pros and cons as well as other things that occur within those different types of suspension. Such as wheelarc.....


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## Alloy (Feb 11, 2004)

j6105 said:


> nada my basis is from watching real life frames at the specialized headquarters. Wow i love this i shook the unshakable zedro, ha gave into temptation and insulted me. Just like the rest.


Some people make it very hard not to judge.


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## j6105 (Apr 10, 2004)

*yes*

i thoroughly acknowledge that zedro is mtbr DH god. But still, what would this forum be if i didn't have my reasoning and he his. When that frame comes in i will admit i am wrong, i have no problem with that if i see evidence, after all, there is still a reason the prototype is around after these super-techno smarter-than-thou programs. 

wait knolly is only this forum, can you tell us about your opinion FSR, becuase really, you know more than anyone here probly ever will


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## COmtbiker12 (Jan 12, 2004)

j6105 said:


> wait knolly is only this forum, can you tell us about your opinion FSR, becuase really, you know more than anyone here probly ever will


It also helps if you use proper grammar so that we may thoroughly understand your intentions.


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## j6105 (Apr 10, 2004)

*true dat*

and i'll admit that is a good point too


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## gunfodder (Jan 13, 2004)

*maybe a concrete example will help*

Take a string grab it firmly with one hand and plant that hand on a table. Call this the bottom bracket hand. Pull the string taut with your other hand so that it is parallel with the table. This is the axle hand. Now try to move that hand straight up. You can only do this by letting more string out of your axle hand. If you move your hand upward without letting more string out your axle hand will follow a curved path that moves upward and forward.

This illustrates that it is impossible for an axle to follow a straight path without changing the length of the chain. Chain growth is what causes pedal feedback. The Linkage program that WheelieMan used demonstrates that FSR linkages generally have very little chain growth, and that this is because the axle path is curved. There is nothing wrong with a curved path; the main strength of the high monopivot is that the rearward motion of the axle makes the suspension plusher. The FSR linkage curves forward deeper in compression to prevent chain growth and minimize pedal feedback.


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## zedro (Jan 12, 2004)

i guess those 6 hour drives make me cranky. Oh well.

what i find funny is why people even believe a vertical wheelpath is a good thing. Its like one of these sub-conscious marketing approaches where if you claim the product does "something", that "something" must be good right?

I remember reading a product blurb on some crappy dept. store type bike that it featured a special sinusoidal shock rate. Wow, sinusoidal shock rate, that thing must be amazing right? Of course, all that meant was that its a single pivot with no shock linkage....


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## BudhaGoodha (Aug 2, 2004)

Skygrounder said:


> okay that was driving me completely frickin nuts....here's a non-seizure-inducing version:
> 
> (edit: btw, thanks for posting that, DJBiker, very cool)


If you look closely, this drawing actually shows the rear dropout curving a little bit. Seeing as how this drawing only shows 2-3inches of compression, it doesn't prove a full vertical travel. This design does however show that it is designed to maintain MORE of a vertical travel than just a standard single pivot. The extra arm system on top helps to rotate the drop out and give it "more" of a vertical path.

Some of you guys are completely oblivious to simple physics. You can't get a perfectly vertical travel from top to bottom UNLESS the chain stay has a way to expand and contract. It's just that simple. Anything that pivots and is solid will never maintain a perfect straight path.

What the heck is the fetish with vertical travel? If anything a fully vertical travel bike would severely suck!


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## shock (Aug 9, 2004)

*That's a perfect example to try...*



gunfodder said:


> Take a string grab it firmly with one hand and plant that hand on a table. Call this the bottom bracket hand. Pull the string taut with your other hand so that it is parallel with the table. This is the axle hand. Now try to move that hand straight up. You can only do this by letting more string out of your axle hand. If you move your hand upward without letting more string out your axle hand will follow a curved path that moves upward and forward.
> 
> This illustrates that it is impossible for an axle to follow a straight path without changing the length of the chain. Chain growth is what causes pedal feedback. The Linkage program that WheelieMan used demonstrates that FSR linkages generally have very little chain growth, and that this is because the axle path is curved. There is nothing wrong with a curved path; the main strength of the high monopivot is that the rearward motion of the axle makes the suspension plusher. The FSR linkage curves forward deeper in compression to prevent chain growth and minimize pedal feedback.


Another thing to think about j6105, is that, without an extra pully system, the only suspension that can have zero chain growth is on that the pivot is concentric with the bottoom bracket, which of course has a curved axle path centered around the bottom bracket.

Obviously the axle could extend to the rear (when the bottom bracket is above the axle) or to the front (when the bottom bracket is below the axle). Most bike extend the rear initially and then to the front, but in ALL cases, chain growth exists. It's a simple matter of the axle getting farther away from the bottom bracket as the suspension compresses. Again, without a concentric bottom bracket pivot, this MUST happen.

BTW, regarding everyones simulation, what they are (all) showing is that the fsr suspension merely represents a single pivot, whose actual pivot cannot exist in in that location due to space constraints. This is true of all fsr or vpp bikes. That's why all the models you see look like they are modelling a single pivot....

Hope this helps


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## shock (Aug 9, 2004)

zedro said:


> i guess those 6 hour drives make me cranky. Oh well.
> 
> what i find funny is why people even believe a vertical wheelpath is a good thing. Its like one of these sub-conscious marketing approaches where if you claim the product does "something", that "something" must be good right?
> 
> I remember reading a product blurb on some crappy dept. store type bike that it featured a special sinusoidal shock rate. Wow, sinusoidal shock rate, that thing must be amazing right? Of course, all that meant was that its a single pivot with no shock linkage....


See, that reminds me of marzocci's amazing "speed sensitive" valving or damping or whatever, when in fact it's almost impossible to not have speed sensitive valving, with oil anyway.....


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## zedro (Jan 12, 2004)

shock said:


> See, that reminds me of marzocci's amazing "speed sensitive" valving or damping or whatever, when in fact it's almost impossible to not have speed sensitive valving, with oil anyway.....


 even funnier because it was speed sensitive in the opposite manner you'd want it to be.


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## shock (Aug 9, 2004)

zedro said:


> even funnier because it was speed sensitive in the opposite manner you'd want it to be.


And really, I just want my suspension to be responsive to my needs (emotionally and physically)


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## BudhaGoodha (Aug 2, 2004)

shock said:


> And really, I just want my suspension to be responsive to my needs (emotionally and physically)


Have too many suspensions not call you back for a second date?


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## j6105 (Apr 10, 2004)

*true dat again*

yeah,
ok i realize that if the suspension is vertical there is chain growth. However, having ridden demo's set up for 120 lb kids and one set up for 200 lb adults, none of them have pedal feedback. The linkage was very darn vertical at the specialized headquarters so i don't understand how there is no pedal feedback? Ideas? zedro i know you know this one.
I really like FSR suspension for just pure plushness and good efficiency. Also, will the rearward axle path on the yeti 303 be enough to actually feel results?


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## TheSherpa (Jan 15, 2004)

j6105 said:


> yeah,
> ok i realize that if the suspension is vertical there is chain growth. However, having ridden demo's set up for 120 lb kids and one set up for 200 lb adults, none of them have pedal feedback. The linkage was very darn vertical at the specialized headquarters so i don't understand how there is no pedal feedback? Ideas? zedro i know you know this one.
> I really like FSR suspension for just pure plushness and good efficiency. Also, will the rearward axle path on the yeti 303 be enough to actually feel results?


Ohh, so your pretty much saying that you were fullofshit before and actually looking for other peoples opinions? Good on ya. The respect level grows.

-TS


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## WheelieMan (Jan 19, 2004)

j6105 said:


> yeah,
> ok i realize that if the suspension is vertical there is chain growth. However, having ridden demo's set up for 120 lb kids and one set up for 200 lb adults, none of them have pedal feedback. The linkage was very darn vertical at the specialized headquarters so i don't understand how there is no pedal feedback? Ideas? zedro i know you know this one.
> I really like FSR suspension for just pure plushness and good efficiency. Also, will the rearward axle path on the yeti 303 be enough to actually feel results?


From the data zedro retrieved a while back, it appears that the 303 does not have a rearward axle path. But keep in mind, the 303 will be adjustable using that steel track thing, so it sounds like the 303 will have adjustable wheelpath and shock rate.


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## WheelieMan (Jan 19, 2004)

Oops forgot, in the animation above the upper track part is straight, but the track actually bends upward toward the end, so it might need some adjusting.


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## tmoney (Mar 1, 2004)

*fsr demonstration*

I came across this demo from specialized website. Dont know what i think about it. Notice that the fsr bike has no chain!

http://www.specialized.com/sbc4Bar.jsp?JServSessionIdroot=n3jnd34bin.j27007


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## Guest (Dec 2, 2004)

WheelieMan said:


> Oops forgot, in the animation above the upper track part is straight, but the track actually bends upward toward the end, so it might need some adjusting.


The pivot isnt supposed to come out of place when the suspension is being compressed?????


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## TheSherpa (Jan 15, 2004)

tmoney said:


> I came across this demo from specialized website. Dont know what i think about it. Notice that the fsr bike has no chain!
> 
> http://www.specialized.com/sbc4Bar.jsp?JServSessionIdroot=n3jnd34bin.j27007


Now Travis, we all know Specialized is so full of **** it comes out of their eyes. That is 100% marketing bullsh!t.

-TS


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## WheelieMan (Jan 19, 2004)

[email protected] said:


> The pivot isnt supposed to come out of place when the suspension is being compressed?????


Im sorry but I dont know what youre talking about.


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## COmtbiker12 (Jan 12, 2004)

[email protected] said:


> The pivot isnt supposed to come out of place when the suspension is being compressed?????


 Have you seen pics of the 303? There is no mounted pivot, and there are vertical and horizontal tracks that the rear triangle moves on.


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## zedro (Jan 12, 2004)

j6105 said:


> yeah,
> ok i realize that if the suspension is vertical there is chain growth. However, having ridden demo's set up for 120 lb kids and one set up for 200 lb adults, none of them have pedal feedback. The linkage was very darn vertical at the specialized headquarters so i don't understand how there is no pedal feedback? Ideas? zedro i know you know this one.


 ok for one thing the axle path is far from vertical or straight and it doesnt take super precise measurements to reveal this; in fact just looking at the linkage (visually and by CAD) i can tell it has an approximate center of curvature just behind and above the lower BB pivot, just like all FSRs have. I took reference points from pics and even moved them around slightly (like errors) and it doesnt affect the axle path to any significant degree (although ICs and suspension rates are contrarily quite sensitive). A simple live bench sighting will not let you make accurate judgements to whats happening; computers give much better representations. I dont understand what you saw or how you saw it, but i am using the same tools i used (and others use) to design bikes.

As for feedback, you wont really feel any BECAUSE THERE IS NO VERTICAL PATH or anything remotly close to one (there is no sense in debating this, it is fact). The path and feedback properties are not all that different from the typical FSRs. What this bike does have is alot of anti-squat, more than the Big-Hit. This is what you dont seem to understand about these linkage systems, is that its about high anti-squat vs. low chain-effects (feedback).

a vertical path would feel terrible, and theres no way to reduce the enormous feedback it would cause without modifying the drivetrain line.


----------



## zedro (Jan 12, 2004)

WheelieMan said:


> Oops forgot, in the animation above the upper track part is straight, but the track actually bends upward toward the end, so it might need some adjusting.


 yeah, and its most likely to reduce feedback by tightening the arc near the end of the travel since the curvature is too large (ie. too "straight" lol).


----------



## knollybikes.com (Jan 8, 2004)

*Not to get dragged into this...*

... but since my name was used I can tell you this:

Vertical wheel path is a mis-nomer: no bike has it (well, maybe the "shockster" that was posted earlier!) and even if someone did make a bike with it, you wouldn't want to ride it.

Vertical wheel path implies a change in chainstay length. "Horst style" four bar linkage suspensions typically arc a bit rearward and then come forward near the end of their travel. To what degree they do this is determined by the pivot placements, but as Zedro said, you can have a fairly large variation in pivot placement and still end up with similar (but not exactly the same) wheel paths.

One of the main benefits of four bar bikes is the fact that the chainstay length doesn't change very much during compression: typically less than 0.5" for a bike of 7-8" travel. There are of course other reasons to use four bar suspensions as well.

Regards,


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## TheSherpa (Jan 15, 2004)

knollybikes.com said:


> ... but since my name was used I can tell you this:
> 
> Vertical wheel path is a mis-nomer: no bike has it (well, maybe the "shockster" that was posted earlier!) and even if someone did make a bike with it, you wouldn't want to ride it.
> 
> ...


So, when are you going to make a 8"-9" travel DH bike??? I'll test a proto.

-TS


----------



## singletrack (Feb 19, 2004)

knollybikes.com said:


> Vertical wheel path is a mis-nomer: no bike has it (well, maybe the "shockster" that was posted earlier!)


 See I wasn't just being goofy.


COmtbiker12 said:


> Have you seen pics of the 303? There is no mounted pivot, and there are vertical and horizontal tracks that the rear triangle moves on


 Just like the Shockster.

It's the future.


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## j6105 (Apr 10, 2004)

*ah c*

wow,
all it takes is man who knows his sh**. Calms me down right away, i hate people that say "specialized sucks". I see your point, my guess is that since the frame had no shock or fork installed, the linkacge was hyper extended as it lay "face first" on the table and when i compressed it i got the rearward-to-vertical part of the travel as the fram moved. I don't know if thats wut happened but whu knows. Also, isn;t the yeti swingarm at a little larger downward angle than that(like 225 degrees as opposed to 200). oh well, hmm the anti-squat characteristics sound interesting, but i don't know much about the low end pedal forces. wow bike design is a bit like phsychology. Just keep delving deeper until everything matters so little, you have more problems than when you started out.(not saying this convo is like that). i must have social and emotional polypolarism at its finest  .


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## TheSherpa (Jan 15, 2004)

j6105 said:


> I see your point, my guess is that since the frame had no shock or fork installed, the linkacge was hyper extended as it lay "face first" on the table and when i compressed it i got the rearward-to-vertical part of the travel as the fram moved. .


Didn't you say it was vertical at the beginning of the thread? 

-TS


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## zedro (Jan 12, 2004)

j6105 said:


> I see your point, my guess is that since the frame had no shock or fork installed, ....


 so you didnt have the proper orientation of the frame either. Any path can appear rearward if its rotated backwards enough, or skewed enough from perspective illusions. I cant believe your only source of "info" for all this bickering came from a frameset laying a table that you visually inspected and analyzed by manually moving the linkage....


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## RED5 (Jan 4, 2004)

*Wow...*

this whole thread has brought back so many memories. 

Don't worry about it j6105, I used to be as disillusioned by SpecialEds hype as you were (are?). But like you Zedro and others made me see the light. Of course that's not to say their bikes s*ck, but I *think* a good SP bike w/ a floater could probably ride just as well. Live and learn.


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## shock (Aug 9, 2004)

BudhaGoodha said:


> Have too many suspensions not call you back for a second date?


Oh sure, they ask me out again, but their motives are always so cyclicly transparent. They just want someone to mount them and bounce up and down and make things slide in and out. That's all well and good, but when it's over I just want them to hold me and ask how my day was........


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## shock (Aug 9, 2004)

red5 said:


> this whole thread has brought back so many memories.
> 
> Don't worry about it j6105, I used to be as disillusioned by SpecialEds hype as you were (are?). But like you Zedro and others made me see the light. Of course that's not to say their bikes s*ck, but I *think* a good SP bike w/ a floater could probably ride just as well. Live and learn.


Or maybe an fsr bike WITH a floater, eh Red5? Oops, did I just start that up again.....dinner's ready, gotta run....


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## BudhaGoodha (Aug 2, 2004)

shock said:


> Oh sure, they ask me out again, but their motives are always so cyclicly transparent. They just want someone to mount them and bounce up and down and make things slide in and out. That's all well and good, but when it's over I just want them to hold me and ask how my day was........


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## RED5 (Jan 4, 2004)

shock said:


> Or maybe an fsr bike WITH a floater, eh Red5? Oops, did I just start that up again.....dinner's ready, gotta run....


 Ah that's OK. I like to spend my money wisely, so no need for a floater. But who knows maybe someday, maybe, I'll buy a bike that requires one. Then you can have my money, if you'll take it next time, I mean since you already said no to taking once.


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## BigDigger (Mar 29, 2004)

Wow, this thread is like an episode of "Dr. Phil" 

j comes in hostile and combative, certain that God himself informed him that the axel path was straight, but after a chat with Dr. Phil (played here by zedro and knolly), he realizes that the axel path isn't straight after all, and that that is OK, and that the real reason for his anger stems from being molested by a single-pivot bike when he was younger. 

Will Phil be able to help him deal with his pain? Tune in next week...


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## Dougal (Jan 23, 2004)

shock said:


> Is that, regardless of axle path, the axle and brake caliper are attached rigidly to the same piece of metal. No pivots in between the axle and the brake caliper. Their path is one and the same. With a floating brake, the caliper is NOT attached to the same piece of metal. This is the only way to remove the braking force from the suspension.


Many of us would incline to disagree. But that has already been established.

The vertical wheelpath claim is whack man. You can't get vertical out of a set of fixed length links, it always comes out as an arc.
Four bars generally have arcs that monopivots can't produce.

Gergely Kovacs writes that linkage software, it's available here http://www.hegyezo.hu/linkage/eng.html

While it's easy to input the bikes, you need to confirm all the physical measurements to get an accurate model, many get distorted.

T-square, tee hee hee.


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## KONA_in_SB (May 20, 2004)

You watch Dr. Phil?


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## DHidiot (Aug 5, 2004)

Okay...how about every moron in this threat stop saying ANYTHING, until someone can get a demo 9 frame held stationary, shock removed, and with a pencil placed in the same axis as the axle, and have the f***ing wheel path physically drawn out on a large sheet of paper oriented to the uncompressed frame and with the whole process documented for everyone to see...so far none of you have come up with a foolproof method of proving this, whether its just someones word or your own assertions or what you plugged into a small animation program (with slightly misplaced pivots I might add)...so until someone does...SHUT THE HELL UP!!


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## zedro (Jan 12, 2004)

DHidiot said:


> Okay...how about every moron in this threat stop saying ANYTHING, until someone can get a demo 9 frame held stationary, shock removed, and with a pencil placed in the same axis as the axle, and have the f***ing wheel path physically drawn out on a large sheet of paper oriented to the uncompressed frame and with the whole process documented for everyone to see...so far none of you have come up with a foolproof method of proving this, whether its just someones word or your own assertions or what you plugged into a small animation program (with slightly misplaced pivots I might add)...so until someone does...SHUT THE HELL UP!!


 your name is perfect. And you understand nothing about suspension. Until you do....



> SHUT THE HELL UP!!


 PS, that computer program will give you much more accuracy even with pivot location errors than your dumb pencil method which wont tell you jack about the CC. That would be the equivalent to designing something on paper using crayons.

PPS, wtf are you bringing up dead threads for? to showcase your retardability?


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## DHidiot (Aug 5, 2004)

Hmmmm to the contrary, I know quite a bit about suspension and how small margins of error arise in computer programs such as the ones shown, being a 3rd year Mechanical Engineering student....I don't need to post my credentials, but I do know what I'm talking about. There is no perfect substitute for a physical test on a production model with a modeling program, although they come quite close.

As long as the paper, the front of the frame and whatever is being used to mark the axle path are perfectly straight and rigid with no play, that will show the axle path perfectly and put an end to this drivel.

I don't know if the path is straight or not, but if it isn't it's damned close (and has come closer than any other bike we could name, except maybe the Yeti DH-9, and I'm still not sure about that one) and Specialized has designed and built one hell of a bike...I hope that we can all agree on, and dissenters will be stoned to death (either method).

Retardability...way to make up words there genius. Would be a shame for you know what it actually would mean if it were a real word.

As for the name, well, anyone who throws themselves down a mountain on a bicycle will be considered an idiot somewhere...guilty as charged I suppose.


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## Jm. (Jan 12, 2004)

DHidiot said:


> I don't know if the path is straight or not, but if it isn't it's damned close (and has come closer than any other bike we could name, except maybe the Yeti DH-9, and I'm still not sure about that one) .


Yes, you are still an idiot.

Look at a yeti DH9. If there was no seatpost and you kept rotating the wheel, eventually it would be almost straight up, it's an ARC, it's not "straight".

It's not rocket science, just make a linkage out of legos or cardboard and see for yourself. It's not some grand deception, it's rather simple.

The only real problem is the brainwashing from Specialized's marketing department, telling us that their bike has a vertical wheelpath and that for some reason we want a vertical wheelpath...


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## DHidiot (Aug 5, 2004)

Sorry, I can't defend or vouch for anything about the DH-9 as I've never taken a close look at it, or even seen one in real life. It's just another bike like the Demo who's designers claim to have made it with a perfectly vertical axle path...whether that's true or not is a different story, but that would be the closest comparison to what Specialized was going for I suppose.

Another thing these companies MAY be taking into account is the change in geometry as the fork compresses as well. Vertical is all relative I suppose and the direction of the perfect vertical may change at different points through the travel.

Just a thought, don't know for sure since I haven't really tested it...


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## zedro (Jan 12, 2004)

DHidiot said:


> Hmmmm to the contrary, I know quite a bit about suspension and how small margins of error arise in computer programs such as the ones shown, being a 3rd year Mechanical Engineering student....


 wow, super impressed. Thats makes you supercaliforagalyrrifically qualified then....

Heres some homework: take a CAD program (if you know how to use one yet) and see how much you can alter the CC from the lower BB pivot on an FSR design. You'll see you cant do very much with it. Thats the point of contention here.

I'm not going by what a little freeware program tells me, i'm going by actually having analysed and experimented with these damn things (on real software) and understanding how they work. Now go do your homework.


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## Jm. (Jan 12, 2004)

DHidiot said:


> Sorry, I can't defend or vouch for anything about the DH-9 as I've never taken a close look at it, or even seen one in real life.


Jesus...you use an example that disproves your point, and then try to argue that you have no knowedge of it...wtf?


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## Shibby (Jan 13, 2004)

There ought to be trophies given out for this sort of thing...


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## Dougal (Jan 23, 2004)

DHidiot said:


> Hmmmm to the contrary, I know quite a bit about suspension and how small margins of error arise in computer programs such as the ones shown, being a 3rd year Mechanical Engineering student....I don't need to post my credentials, but I do know what I'm talking about. There is no perfect substitute for a physical test on a production model with a modeling program, although they come quite close.


Sorry son but the real engineers here (who've debated suspension design for years) aren't agreeing with you.



DHidiot said:


> I don't know if the path is straight or not, but if it isn't it's damned close


I do hope sometime before you graduate, that you learn how hard it is to get a straight path from a four bar linkage.


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## DHidiot (Aug 5, 2004)

Dougal said:


> Sorry son but the real engineers here (who've debated suspension design for years) aren't agreeing with you.
> 
> I do hope sometime before you graduate, that you learn how hard it is to get a straight path from a four bar linkage.


Um, what aren't they agreeing with exactly? I didn't know I had a panel of engineers looking at my posts... I haven't said anything one way or another about the axle path being perfectly vertical or not, since I DON'T KNOW. Clearly nobody else here does either for certain, since we aren't the original designers and don't have the dimensions as precise as the engineers/designers.

As for the DH-9, no I do not know any real specifics of the frame, but that is one frame that I have heard rumors about having to do with a perfectly vertical axle path, that is all. READ WHAT I SAY THE FIRST TIME PLEASE.

And I do know how hard it is to get a perfectly straight path from a 4bar linkage, if not impossible on a mountain bike. Once again, don't know for sure if it is or not since I haven't done a whole lot of experimenting with it, but I know it would be damned hard if it were in fact feasible. I have a pretty good history with CAD, and I do know that unless you have the exact assembly with the same dimensions that Specialized made their bikes off of, the model animation will not be 100% accurate. Without that, the only thing us consumers are left with is a physical test from the bike itself for a completely correct answer.

I do agree that having a perfectly vertical axle path would cause a lot of drivetrain problems, so we probably don't want that and my GUESS is that Specialized knows that as well.

SOME people here really need to learn to both read AND understand what's written...


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## BJ- (Jan 28, 2004)

DHidiot said:


> Um, what aren't they agreeing with exactly? I didn't know I had a panel of engineers looking at my posts... I haven't said anything one way or another about the axle path being perfectly vertical or not, since I DON'T KNOW. Clearly nobody else here does either for certain, since we aren't the original designers and don't have the dimensions as precise as the engineers/designers.
> 
> As for the DH-9, no I do not know any real specifics of the frame, but that is one frame that I have heard rumors about having to do with a perfectly vertical axle path, that is all. READ WHAT I SAY THE FIRST TIME PLEASE.
> 
> ...


*DIE* old thread...

take this as your offical warning...

-your friendly neighbourhood "*search function*" natzi BJ...


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## zedro (Jan 12, 2004)

DHidiot said:


> ...........I didn't know .............since I DON'T KNOW. .................no I do not know any real specifics ................I have heard rumors .............don't know for sure if it is or not ..............my GUESS.......
> 
> SOME people here really need to learn to both read AND understand what's written...


 why are you still talking? you have nothing to contribute to this....


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