# Curved ti seat stays. Is there really a comfort advantage ??



## martino (May 11, 2009)

Good morning to you all,
I've been checking out the various ti-bikes being offered around the world and there certainly seems to be 2 schools of thought regarding curved, straight or even s-bend rear stays. So i'm appealing to all of you with real experience, meaning you've ridden the various styles and have formed an opinion. 
What I'm after is the max on comfort (vertical compliance), my riding style is very relaxed 2-3 hour rides with nothing even resembling comptetition.
I realise of course that the question is very subjective and there's going to be more than one opinion out there, but at the same time your ass isn't going bs you after 3-4 hours in the saddle. I'll be eternally gratefull for any shared experience's.
Martin


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## Mike T. (Feb 3, 2004)

I have both a Ti mountain bike with s-bend stays and a Ti road bike with straight ones so it's not possible to directly compare but think about this - with about 1/2" of flex available from a properly inflated 25mm road tire and maybe a few thousandths of an inch from any curved stay, do you really think the stays would make any noticeable difference?

If you want comfort then get the biggest road tires possible. I had some Challenge Grifo diamond tread cyclocross tires on my dirt road bike (335g, 33mm wide, approx 50psi) and they felt like I was riding on feather pillows compared to my road bike with 25mm tires inflated to 90psi.

I used that bike for hard training rides on dirt & paved roads and I was 1mph slower (average speeds) than on my road bike. I also did the same rides on my mountain bike with 2.1" tires at 40psi and I was about 1.5mph slower than on my road bike.


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## danl1 (Jul 23, 2005)

I've ridden a radius-curved Litespeed for years, and just this year picked up a custom with straight stays. 

I don't have enough miles on the new bike to give a definitive answer, but both Logic and butt sense agree with Mike. If there is a noticeable effect it is tiny, and would necessarily be limited to a narrow band of amplitude and frequency. 

Consider swooped stays an aesthetic choice, and s-bends functional only as they impact tire clearance. (Which usually isn't a problem on most road designs)


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## Peter P. (Dec 30, 2006)

I can't answer the question about the curved stays, but there's one custom framebuilder who truly believes in them; Dave Kirk.

As I just answered in another thread; I with the above answers; vertical compliance in a frame is very limited and likely of little benefit. It's a double triangle structure, which they design bridges with to give them vertical strength so they don't sag under the weight of traffic. The only comfort you'll get is from the flex of the fork.

The little known secret to comfort is to experiment with tire pressure. Drop your tire pressure 5psi. per ride until you start to feel the tire bottom out, then go back up in pressure 5-10psi. Done. For comparison, I'm 135lbs. and ride 23mm tires at 75-80psi. If you need more volume, go up in tire size and repeat the experiment.

All your cushioning is going to come from your tires, not your frame.


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## martino (May 11, 2009)

danl1 said:


> I've ridden a radius-curved Litespeed for years, and just this year picked up a custom with straight stays.
> 
> I don't have enough miles on the new bike to give a definitive answer, but both Logic and butt sense agree with Mike. If there is a noticeable effect it is tiny, and would necessarily be limited to a narrow band of amplitude and frequency.
> 
> Consider swooped stays an aesthetic choice, and s-bends functional only as they impact tire clearance. (Which usually isn't a problem on most road designs)


thanks to all,
Peter thanks, thats exactly what I'm talking about, people with experience on both styles. I'ld love to hear more once you collect a few miles-killometer, certainly lightspeed and linskey both claim a benefit but at the end of the day people claim a lot of things.
As far as air pressure goes, Mike T. & Peter P., I got the message this summer and even invested in Topeaks airpressure messuring device, with which I'm still in the experimental phase of dailing in. 
My main concern was-is there a significant improvement or are they just covering all the bases in case someones still on the fence as to which frame to buy.


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## Mike T. (Feb 3, 2004)

martino said:


> My main concern was-is there a significant improvement or are they just covering all the bases in case someones still on the fence as to which frame to buy.


It's almost all marketing & hype. What little bit isn't isn't worth bothering about. Go for what looks best to you. I have a curvy stay Seven Sola and for my latest Ti frame chose a Kish done as plain-jane as possible with straight stays. Get something custom made and tell them how you want it to ride and they will tailor it to your needs (if that isn't all hype too). But still, I don't care what you get, straight stays with 50psi tires will ride smoother than stays bent in the shape of double-bend bananas with 110psi 23mm tires.

Go for what *looks* best to you.


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## danl1 (Jul 23, 2005)

martino said:


> ... certainly lightspeed and linskey both claim a benefit but at the end of the day people claim a lot of things.
> ...
> My main concern was-is there a significant improvement or are they just covering all the bases in case someones still on the fence as to which frame to buy.


In my opinion, this. Depends on the marketing slant of the moment, but if you look at the ad copy that says what the bike is meant for and how it should feel, and compare that across the frames they make that are curved or straight - you won't really find much consistency. 

I will allow that a rear end as curvaceous as the Kirk Terraplane stays may have a more substantial effect. Dave is said to have come up with that concept while working with Serotta; their Hors Categorie model had radically bent Ti stays that included an elastomer dampener. But the "normal" bends as in Lynskey's line (very similar to my Litespeed Solano) sorts seem to have little real-world flex available to them, especially when welded on both ends, which locks down the geometry still more. (The Serottas have a sort of pivot at the dropout that they claim helps things move.)


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## Len J (Jan 28, 2004)

Read what Dave Kirk says about his terra plane stays. http://www.kirkframeworks.com/Philosophy.htm

Notice, he designs different curves for different rider weights......then think about stock designs. 

I have both a Kirk terra plane and a Serotta Ottrott with the pivots.....both add some small comfort improvement, but are more effective at keeping the rear wheel planted on sketchy roads. Larger tires have more of an impact on comfort IME. 

Len


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## martino (May 11, 2009)

Len J said:


> Read what Dave Kirk says about his terra plane stays. Kirk Frameworks Custom Bicycles - Bicycle design and construction
> 
> Notice, he designs different curves for different rider weights......then think about stock designs.
> 
> ...


Well you certainly have some superb bikes to base your opinions on and that in itself is a strong arguement to go with the optics that i prefer with room for long cliper breaking.
I've got my eye on a Brit. bike builder named Burls, he gets his ti frames built to his specks in Russia. Bottom line, I can have it anyway I want it.
Martin


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## velodog (Sep 26, 2007)

If comfort is what you're after, have you given any thought with a bike with 650b tires and wheels?

This one isn't titanium but it'll give you a visual of a bike with that tire size. From 32mm/285grms up to 38mm/412grms.

Just a thought.


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## DJT21 (May 22, 2011)

Ignore the seatstay shape, get a comfy saddle and a comfy seatpost.


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## Kerry Irons (Feb 25, 2002)

martino said:


> My main concern was-is there a significant improvement or are they just covering all the bases in case someones still on the fence as to which frame to buy.


Are you comparing a bike with thick-walled large diameter curved stays to one with thin-walled small diameter straight stays? Do you get the concept that only looking at one parameter (curved vs. straight) is pointless without taking the entire frame geometry and tubing details into account? Same question could be asked about straight vs. curved forks and the answer is the same - there are a whole bunch of factors that come into play that COMBINE to make one frame more comfortable than another (assuming they both fit properly). And what Mike T. said about tire pressure/size still holds.


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## aclinjury (Sep 12, 2011)

Here are my input based on bikes I've ridden extensively.

I will list them in the order of most comfortable to least comfortable.

Serotta Ottrott - with carbon downtube & toptube, titanium seat tube, chain stays, and seat stays (curved). Carbon fork. 

Specialized Roubaix - all carbon

Litespeed - all titanium, curved seat stays (but don't appear to be as curved as the Serotta's). Carbon fork.

Casati Laser - full Columbus genius cromoly frame, straight seat stays

Serotta Meivici - all carbon frame, with the curve seat stays. Carbon fork.

Cyfac Nerv - aluminum front, carbon chain and straight seat stays

Cadd 10, Cyfac Proxidium (All these are full aluminum).

To me, the Ottrott is sooo freakin comfy that I would NOT want a road bike to be any more comfortable. I don't now if the comfort is due to the curved Ti stays alone, but I think it has more to do with the design of the whole bike.

On the other extreme, I would not want to ride a Cadd or Proxidium in anything other than a 1hr crit.

You can also run a larger tire at a bit lower psi. But IMO a 25c tire at 10 psi less is not that much more comfortable. You would need to go to a much larger sized tire that will allow you to go down to 50 psi. However, there is also an issue with larger tires at low psi too. When you descend on such large tire at low psi, you lose a lot of control in fast corners and under hard braking. Large low psi tire are like off-road truck tires, good for the mud and rough surface, but crappy in fast descend and braking.

I would not go for a seat that is cushy. All that will do is get your butt numb once the seat goes soft on the inside, and it will. 

A carbon seat post is more comfortable than an aluminum one.


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## martino (May 11, 2009)

Kerry Irons said:


> Are you comparing a bike with thick-walled large diameter curved stays to one with thin-walled small diameter straight stays? Do you get the concept that only looking at one parameter (curved vs. straight) is pointless without taking the entire frame geometry and tubing details into account? Same question could be asked about straight vs. curved forks and the answer is the same - there are a whole bunch of factors that come into play that COMBINE to make one frame more comfortable than another (assuming they both fit properly). And what Mike T. said about tire pressure/size still holds.





DJT21 said:


> Ignore the seatstay shape, get a comfy saddle and a comfy seatpost.


Kerry, I don't think you have to go to far to realize I wasn't comparing curved lead drainage pipes with state of the art straight ti pipes, but thanks for your concern anyway. What I'm asking is if, lets say Linskey, builds 2 bikes with the same specs apart from 1 with curved stays and 1 with straight stays will there be a discernible difference???
I'm becoming more convinced that the real answer as many of you have stated, lies in the right seat post and tire pressure. Although it has to be said that the seat post, for max comfort, should be a 27.2 diameter.
The Serotta Ottrott is perhaps stacking the deck a little due to the pivotal connection between s.s and c.s. and unfortunately out of my $$ range (otherwise my search would be over and I'ld be riding an Ottrott), it's certainly one of the most impressive bikes on this planet IMHO.
I think what I have to do now is debunk the whole tube-specific rhetoric out there which so many coustom builders refer to. Now I'm sure there is a certain amount of magic they can perform but how many different diameter ti pipes are there really ?
I'm 68k or 150lbs which lets out just about every oversized tube on the planet assuming they're to stiff, so what is a builder left with? Maybe 1 or 2 different dia. left in his box of tricks, so is it really that complicated. At this point I have to say that I'm assuming what I just said tubing sizes and it is in no way meant to belittle anyone or there profession, please see it as a question rather than a statement based on any real knowledge. Every profession has its own hype and I respect that, I'm simply trying to see through the forest to the trees. But perhaps this is food for a differant thread.

martin


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## danl1 (Jul 23, 2005)

martino said:


> I think what I have to do now is debunk the whole tube-specific rhetoric out there which so many coustom builders refer to. Now I'm sure there is a certain amount of magic they can perform but how many different diameter ti pipes are there really ?
> I'm 68k or 150lbs which lets out just about every oversized tube on the planet assuming they're to stiff, so what is a builder left with? Maybe 1 or 2 different dia. left in his box of tricks, so is it really that complicated. At this point I have to say that I'm assuming what I just said tubing sizes and it is in no way meant to belittle anyone or there profession, please see it as a question rather than a statement based on any real knowledge. Every profession has its own hype and I respect that, I'm simply trying to see through the forest to the trees. But perhaps this is food for a differant thread.
> 
> martin


The size-specific question is more a differentiation between custom and stock rather than among custom builders, IMO. You are right that by the time you've specified general weight and size parameters and given a sense of desired ride, most accomplished builders will likely come to the same conclusion. But not necessarily. Bikes do have personalities that come from who makes them, and combinations could be varied to acheive different results.

So, not much to debunk here. but that comes with a warning: The above presumes that the custom builders are doing custom at a certain level of professionalism. "bargain custom" is more likely to be using a narrow stock of tubes and only customizing geometry - losing most of the custom advantage over stock, unless someone is oddly sized enough for main dimensions to really matter.


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## aclinjury (Sep 12, 2011)

You are not going to find a manufacturer who will make a bike with a curved Ti seatstays, and also the exact same bike with straight Ti seat stays.. so you will never know this comparison.

However, I have both the Serotta Meivici and Ottrott, one using curved carbon stays, the other using curved Ti stays,.. and I can tell you that in term of comfort, the 2 bikes are world apart. The Ottrott feels like a couch compared to the Meivici. And the Meivici also has the same "pivots" as the Ottrott. Whatever Serotta is doing, they sure know how to build a bike to have certain characteristics.

Every now and then, I do see a couple of immaculate Ottrott's on Ebay, but asking price aint cheap, usually over $3000, but still half price of a new one.

A carbon seatpost will damp your butt, but you will still feel the jarring at your feet! However, larger tires will damp both your feet and your butt, but like I said before, larger volume tires will also decrease your performance especially when descending (if you dont mind this decrease in performance, then go for large tires). 

However, if you want the best of performance (meaning using 23/25c tires, and not bigger tires), and still have damping on your feet and butt, then you need to get a good frame. There is no substitute for a good frame.


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## Mr Evil (Aug 12, 2011)

The idea of curved seatstays has always seemed a little dubious to me, because

1) Being part of a triangle, they can't flex unless something else also flexes, and I'm sure it can't be good for either the chainstays or seat tube to bend to any significant degree.

2) If they bend very much, it will affect the position of the brake pads relative to the rim.

Now, maybe on a bike with disc brakes, if the chainstays were attached to the BB with a hinge...


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## Mike T. (Feb 3, 2004)

Mr Evil said:


> The idea of curved seatstays has always seemed a little dubious to me, because
> 1) Being part of a triangle, they can't flex unless something else also flexes, and I'm sure it can't be good for either the chainstays or seat tube to bend to any significant degree.
> 2) If they bend very much, it will affect the position of the brake pads relative to the rim.
> Now, maybe on a bike with disc brakes, if the chainstays were attached to the BB with a hinge...


I was having a custom steel mountain bike frame built years ago and I happened to drop in on the builder when the chainstays were fixed but the seat stays were not yet on the frame. I remember him almost doing dips on those chain stays when pushing down on them and saying that there was no flex there. Imagine the effect of welding in the third side to that triangle?

Unless a frame has built-in rear suspension I'll bet the rear end compliance of any frame could be measured in thousandths of an inch on the fingers of two hands at the most.

And yes, I'm aware of frames like the Moots YBB -

https://blackmountainbicycles.com/images/library/Zoom/moots_psychloybb_08_z.jpg

And John Castellano's Silk Ti chainstays (and shock absorbing seat stays) -

https://www.ibiscycles.com/images/uploads/wygwam/ScotSilkTi.jpg


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## charlox5 (Jan 31, 2011)

aclinjury said:


> You are not going to find a manufacturer who will make a bike with a curved Ti seatstays, and also the exact same bike with straight Ti seat stays.. so you will never know this comparison.


Lynskey makes the sportive and the cooper, which are the same frame, one with curved seat stays (sportive) and the other with straight (cooper). Though, i'm no expert and may be mistaken.

My R330 has curved seat stays. when i first got it, I found it to be less "magic carpet ride" than my vintage bianchi. maybe the fork i'm using (Alpha-Q GS-40) isn't conducive to great ride quality. I did love the bike even though it wasn't as smooth as I expected. 

however, the biggest upgrades in terms of ride quality have come from wheels and tires. I used to run Conti GP Force/Attacks on the bike. In addition to a bad ride, the flats were too much for me. 23c Lithion 2's were a big step up from the conti's in terms of ride quality. 25c GP4000s' were an even better improvement. Being able to drop pressures to 95/100 (i'm 200 lbs) on the 25's was great. After a groupset shift to campagnolo, i built a set of 23mm HED C2 wheels, and are running those with the GP4000s at 90/95. The final upgrade was latex tubes, which I found to be noticeably more comfortable than butyl. 

Now the bike is incredibly plush. Would it be equally plush if i were on a carbon or aluminum bike? I don't know. But I really enjoy riding my bike right now. 

So, like others have said curved vs. straight is probably a very subtle difference in ride quality--but there are other things that will have a much larger effect on ride quality and probably won't have as much as price impact.


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## aclinjury (Sep 12, 2011)

I agree with a lot of what you said.

The other things that affect stiffness/ or comfort if the thickness of the tubes and the diameter of the tubes. A lot of these "high performance" racing bikes with super thin but oversized tubes... feel very tinny and don't absorb vibration very well, yes even if they're made out of carbon fiber. Examples are the Tarmac and Evo, these two bikes are just rough to ride despite being all carbon. If a bike is too light, that means it doesn't have a lot of mass material, which means it has a decreased capacity to absorb shock via the virtue of mass.

One can certainly change a lot of components on a bike from seatpost to tires to wheels to stems to handlebar and even shoes, in order to maximize comfort. However, when one frame is inherently more comfortable to the next to start with, then you have a head start in the comfort department. You can either spend time and money experimenting with components to make a rough bike become a smooth bike, or buy a comfortable frame to start. And I think that if you have to spend $1000 more to get a frame you want, then spend the extra $1000 as this is better investment than spending on a frame that doesn't meet your requirement for "comfort"... and then spending all that money later upgrade components trying to make a bike comfortable.

fyi, for comparison, I've tried the Lynskey R330, and I can say it's not as comfy as the Ottrott, not close in my mind. I've tried many metal bikes from brand name makers, and can honestly say the Ottrott is one of the most comfortable sportive bikes out there. But also to be fair, the Ottrott also flexes more than other bikes when hammering out of the saddle, but you don't ride an Ottrott like this, guys riding Ottrott are usually the older guys looking to enjoy a relax & pleasant yet perhaps spirited saddle time spinning, not pow-pow hammerheads.



charlox5 said:


> Lynskey makes the sportive and the cooper, which are the same frame, one with curved seat stays (sportive) and the other with straight (cooper). Though, i'm no expert and may be mistaken.
> 
> My R330 has curved seat stays. when i first got it, I found it to be less "magic carpet ride" than my vintage bianchi. maybe the fork i'm using (Alpha-Q GS-40) isn't conducive to great ride quality. I did love the bike even though it wasn't as smooth as I expected.
> 
> ...


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## velodog (Sep 26, 2007)

Wouldn't the comfort of the frame come from the top tube? That is why the TT on a SL steel bike is 24.4(.8-.5-.8) diameter compared to 28.6 on the 
DT(.8-.5-.8) and ST(.8-.6). Smaller diameter same thickness equals more flexible.


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## mrwirey (May 30, 2008)

*I'm with Mike...*

Curved seat stays add sex appeal and do nothing for the ride. It is all in the tires and pressures...that is where the magic is. I could be a friggin' bike shop with all the bikes, wheels, and tires I own; have owned. I rode the 97 Mile Cochise County Cycling Classic (CCCC) this year on a 1995 Cannondale R900 with Zipp 101s and Kenda Kaliente tires set at 90psi. (It’s a nostalgia thing with the only stock component left on the Cannondale being the bare frame.) We are renowned here in southern Arizona for our crap chip-sealed roads. I finished in 4:06ish with no ill effects. The bike did not beat me up and in fact rode like a champ. The wide Zipps with decent tires set at decent pressure made all the difference. Two months later I rode the 111 Mile El Tour de Tucson on my 2007 Bianchi 928SL (lugged carbon) with Shamal Two Way Fit and Hutchinson Fusion/Atom Combination (Tubeless) set at 100psi. The roads in the 'El Tour' are even crappier (except maybe a two mile stretch) than the CCCC. I finished in 4:39ish and wished I'd have run 90psi vice 100psi. I believe tubeless and/or wide wheels with good tires and well thought out tire pressures set for the conditions will make any bike ride comfortably. Running max tire pressure on skinny wheels will make almost any bike ride harsher than necessary regardless of seat stay shape. That said I have found there is a sweet spot to tire size and tire pressure for me (700 x 25C at 90-95psi). I’ve found going much larger than 700x28C begins to take away from the agility, responsiveness, and handling of a modern race bike. I’m no rocket scientist, but it ‘feels’ like it is due to the added gyroscopic effect of the heavier wheel combination (or something). Bottom Line: Comfort is mostly about things wheel (and smooth roads)...not curvy stays.
Very respectfully, Tim

My three Ti bikes as of today...two with curved stays and one with straight stays:


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## dcgriz (Feb 13, 2011)

velodog said:


> If comfort is what you're after, have you given any thought with a bike with 650b tires and wheels?
> 
> This one isn't titanium but it'll give you a visual of a bike with that tire size. From 32mm/285grms up to 38mm/412grms.
> 
> Just a thought.


Beautifully executed Weigle Rando! From the Berthoud saddle to the Herse cranks.


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## aclinjury (Sep 12, 2011)

Some of you are intermixing the notion of "comfort".

If the question is: do curved stays make a bike comfortable, then the answer is, "not necessarily true". Because there are lots of factors (material, tube thickness, tube diameter, geometry, joint contruction, and of course tires) that go into determining the final "comfort level" of a bike.

But if the question is: do curved stays have an advantage in comfort over straight stays, then the answer is clearly yes (everything else being equal, of course). This is no hype, it's fact.

And running big soft tires at low psi also is not without drawbacks.

My philosophy is everything starts with the frame... because as we say in the motorcyle world.. you can only polish a turd so much.


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## Kerry Irons (Feb 25, 2002)

martino said:


> What I'm asking is if, lets say Linskey, builds 2 bikes with the same specs apart from 1 with curved stays and 1 with straight stays will there be a discernible difference???
> I'm becoming more convinced that the real answer as many of you have stated, lies in the right seat post and tire pressure.


You may have picked up on the point that a quality builder would not use the same tube wall thickness and diameter for those two different designs - at least not if they were going for the same design goal.

One of the main thing that influences FRAME comfort (not attributable to tires, tire pressure, saddles, etc.) is the geometry. A frame with a steep seat tube angle and/or short chain stays will put the wheel more directly under the rider and will ride more harshly.

Those who say chains stays don't flex seem to have forgotten that there have been several bikes over the years designed exactly to do that with either linkages or rubber dampers built into a wishbone seat stay. You can easily design seat stays that flex. Ti is a good frame material with which to execute such a design, though I personally have never felt the need for such.


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## adipe12 (Oct 29, 2013)

unfortunately people have little understanding of lateral flex, torsional flex and radial/vertical frex.

unfortunately, if i were to tell you that the primary purpose of that shape is to provide the frame with a dynamic rigidity and have some sideway (lateral) flex in some moments of the ride it would make many of you say i'm doped.

unfortunately most of you would have a headache if i were to explain how tensile strain affects torsional rigidity for the tube the tensile stress has produced the strain to.

so, maybe it's better just to describe the frame design as some engineering witchcraft that we should not investigate for fear of being struck by lightning bolts.

and we should not ever dare to say that lateral flex in some parts of the bike frame has some purpose to it.

right?...

---
long story short but not too short:
with that frame design the seatstays flex under pedalling torque. the compressive stress they experience makes them not only more compressed but also further curved as to permit the chainstays to flex upwards. well, not both of the chainstays (and seatstays) in the same ratio but depending on which side of the bike you press down when pedalling. that happens to a greater effect when climbing out of the saddle. the (undectectible to the eye) flexing of both chainstay and seatstay make the rear triangle have a dynamic rigidity concerning the lateral flex and torsional flex. the chainstays are not as compressed as with the case of straight stays but are also expressing both flexural AND TENSILE strain and that, my friends affects the lateral and torsional rigidity of the tube. as a result the wheel will magically be in a better alignment with the rider's behind. the wheel/tire will have a smoother, better traction without you even knowing why. oh, but of course, you are obsessed with the inherent loss of power, right?... you wouldn't want a bike that was designed to have a variable lateral/torsional rigidity on the rear triangle, influenced by the pedalling torque, right? you'd be rather worried that the flex would make a slower ride, that you'd be robbed of power and not be able to ride with the champs or at least with the same gear as the champs.

important point: the design some dude had in mind was to have *the rear triangle stiff enough* when going downhill or when leaning into a corner but also having a *slightly lower lateral and torsional rigidity for the rear triangle when pedalling hard*. so, the rigidity is dynamic. the invention is not new, it's been around for a while. it started with *hetchins*. very few people cared for this mystery to solve or tell others about.

maybe the engineer that designed/copied the curved stays understood the trick but he certainly doesn't have much say as to what other marketing people tell you.

they just sell you the magic ride and abstain from giving that kind of information that would scare you away. they'd better let you think that rear triangle design offers you comfort instead of telling you there'd be a very, very little loss of power from frame flex but also the loss of power from the tire skidding on the road without you even knowing would be lessened to a greater extent. *you would not believe that. so you are not told.*

so, again, that rear triangle curved seatstays design provides very, very little comfort overall. it's all about smoothening the transfer of power to the tire and lowering the risks of skidding and accidents.

it is impossible to have satisfyingly high lateral and torsional rigidity of the main triangle tubes AND have too much vertical/foreandaft flex - with regards to the main triangle tubes. even if you would try to do that you couldn't. nobody can.

and again, *rear frame triangle is a diferent thing*. the frame design not always focuses on having maxed lateral and torsional rigidity for that part.

it's just cheaper bikes/frames gets more sold if people are indoctrinated as to believe the marketing buzz they are thrown in their face.

on good quality, heat treated steel and titanium alloys, flex is more of a concern regarding stability and NOT regarding fatigue or power loss/efficiency. you have to differetiate between the main triangle flex and the rear triangle flex. not only understand vertical, lateral and torsional but also main triangle and rear triangle flex.

people sell all sorts of books making you feel good. likewise, bikes are sold with a placebo effect. but if johnny were to sell you some well designed bike and be 'honest' about it when he tells you what reasons were those that made the engineer design it that way... screw it. he wants to sell the bike, not educate you. at least when he's on the job. almost everybody thinks this way. you either make the money you're supposed to make or you get dumped by the competition selling crap but being 'wise': forgetting about moral principles. seriously now, how many people do you know to afford 'keeping a conscience'?

which of these two would you rather like?
"four legs good, two legs bad"
or
"nomina rutrum rutrum"


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