Opinions on aluminum frames?

[Archer]

I know Aluminum frames have had a reputation (deserved or not) of being stiff, and I'm wondering if
that's still true, with the different alloys they use now. My current bike is a 20+ year old
steel-framed Schwinn LeTour (a.k.a LeTank).

I'm looking at a Specialized Sequoiah Expert or equivalent, and there seems to be a lot to choose
from in that range. Pretty much all the bikes in that price range seem to have aluminum frames with
carbon forks, and I'm curious how the ride might compare between the two (leaving the suspended seat
on this particular model out of the equation). The LeTour has 27 x 1.25, 85psi tires, and the
Sequoiah has 700 x 26c tires, but I don't know the pressure.

Opinions, please?

--
David Kerber An optimist says "Good morning, Lord." While a pessimist says "Good Lord,
it's morning".

Remove the ns_ from the address before e-mailing.

 

[B. Sanders]

"archer" <ns_archer1960@ns_hotmail.com> wrote in message
news:[email protected]...
> I know Aluminum frames have had a reputation (deserved or not) of being stiff, and I'm wondering
> if that's still true, with the different alloys they use now. My current bike is a 20+ year old
> steel-framed Schwinn LeTour (a.k.a LeTank).

Aluminum has come a long way. My Klein Attitude (mountain hardtail) feels perfect - stiff, light;
but doesn't beat me up like my old Cannondale used to. With aluminum, it's all about the
engineering.

> I'm looking at a Specialized Sequoiah Expert or equivalent

> Pretty much all the bikes in that price range seem to have aluminum frames with carbon forks

That's the most popular combination these days.

> and I'm curious how the ride might compare between the two (leaving the suspended seat on this
> particular model out of the equation).

It's been a lo-o-o-o-ng time since I sold my good old LeTour; but I can just about guarantee you
that any new aluminum/carbon road bike will feel "quicker" in every respect, and will amaze you at
its lightness and "flickability" (as I call it). You'll want to sprint out of the saddle, and it
will feel like a rocket ship compared to your LeTour. However, that stiffness comes at a price in
comfort, and the suspension post is probably a good idea. I think it was Gary Klein who said "I'd
rather have a cheap steel frame than a poorly engineered aluminum frame."

As with any bike purchase, ride as many bikes as you can before making your decision. Make sure that
the test bikes are setup correctly, and that they fit you (adjust saddle height and fore/aft
position, etc). This makes all the difference in getting the bike that's right for you.

> The LeTour has 27 x 1.25, 85psi tires, and the Sequoiah has 700 x 26c tires, but I don't know the
> pressure.

The 26c tires are nice for rougher roads, and shouldn't diminish speed very much. The road bike
standard these days is 700 x 23c, which is a good compromise for all but the roughest roads.

Hope you find the perfect bike.

-Barry

 

[Archer]

In article <[email protected]>, [email protected] says...

...

> > Pretty much all the bikes in that price range seem to have aluminum frames with carbon forks
>
> That's the most popular combination these days.

Thanks for confirming my observations.

> > and I'm curious how the ride might compare between the two (leaving the suspended seat on this
> > particular model out of the equation).
>
> It's been a lo-o-o-o-ng time since I sold my good old LeTour; but I can just about guarantee you
> that any new aluminum/carbon road bike will feel "quicker" in every respect, and will amaze you at
> its lightness and

I _know_ there's going to be a huge difference there. My LeTour is over 30 lbs, with steel rims, so
it isn't exactly a drag racer coming off the line. The lightness will be nice, but durability and a
reasonably comfortable ride are more important to me (not to the point of going to a "comfort" bike,
though; I still like to ride fast).

...

> As with any bike purchase, ride as many bikes as you can before making your decision. Make sure
> that the test bikes are setup correctly, and that they fit you (adjust saddle height and fore/aft
> position, etc). This makes all the difference in getting the bike that's right for you.

That's why I'm taking my time at this (along with getting the money saved up <Grin>)

> The 26c tires are nice for rougher roads, and shouldn't diminish speed very much. The road bike
> standard these days is 700 x 23c, which is a good compromise for all but the roughest roads.

That's useful to know. My usual exercise routes are mostly in pretty good shape, but there are a
couple of sections where the pavement is really chopped up.

> Hope you find the perfect bike.

That's what I'm working for, and by the time I have the money saved up to buy it, I'll have had
plenty of time to do research.

Thanks for the comments!

--
David Kerber An optimist says "Good morning, Lord." While a pessimist says "Good Lord,
it's morning".

Remove the ns_ from the address before e-mailing.

 

[Matt O'Toole]

archer wrote:

> I know Aluminum frames have had a reputation (deserved or not) of being stiff, and I'm wondering
> if that's still true, with the different alloys they use now. My current bike is a 20+ year old
> steel-framed Schwinn LeTour (a.k.a LeTank).
>
> I'm looking at a Specialized Sequoiah Expert or equivalent, and there seems to be a lot to choose
> from in that range. Pretty much all the bikes in that price range seem to have aluminum frames
> with carbon forks, and I'm curious how the ride might compare between the two (leaving the
> suspended seat on this particular model out of the equation).

All normal bicycle frames are completely stiff in the vertical direction, no matter what they're
made of. The flex in the saddle and tires is many times greater than the miniscule amount of flex in
the frame. There's an article in the FAQ which explains this further:

http://draco.acs.uci.edu/rbfaq/FAQ/8e.2.html

The bottom line is that frame material doesn't matter.

> The LeTour has 27 x 1.25, 85psi tires, and the Sequoiah has 700 x 26c tires, but I don't know the
> pressure.
>
> Opinions, please?

Tires *will* make a difference. Bigger is smoother, and not necessarily slower. However, the 28mm or
so that most frames will take is big enough for most people.

Matt O.

 

[Peter Cole]

"B. Sanders" <[email protected]> wrote in message
news:[email protected]...
> "archer" <ns_archer1960@ns_hotmail.com> wrote in message
> news:[email protected]...
> > I know Aluminum frames have had a reputation (deserved or not) of being stiff, and I'm wondering
> > if that's still true, with the different alloys they use now. My current bike is a 20+ year old
> > steel-framed Schwinn LeTour (a.k.a LeTank).
>
> Aluminum has come a long way. My Klein Attitude (mountain hardtail) feels perfect - stiff, light;
> but doesn't beat me up like my old Cannondale used to. With aluminum, it's all about the
> engineering.

That's silly. There's no difference in "frame comfort", it's all in your head. I have a Cannondale
(your worst-case) and I have an old Schwinn LeTour (picked up at a swap meet 2 years ago), there's
no difference in "frame comfort".

 

[Jon Isaacs]

>The LeTour has 27 x 1.25, 85psi tires, and the Sequoiah has 700 x 26c tires, but I don't know the
>pressure.
>
>Opinions, please?

The Sequioa I saw recently looked like a reasonable bike, it had "normal reach" brakes rather than
the standard short reach. Normal reach brakes allow you to use larger tires and fenders too,
something I think is a good idea.

The ride of the bike is determined by the tires and the tire pressure. I believe those old 1.25 x 27
inch tires at 85 psi probably provide a softer ride than the 700C x 26 mm tires, but you can easily
change those to a larger tire.

Just for a point of reference, I did have one of the original Cannondales, the ones reputed to have
that "beat em" ride. I did quite a few 100 mile plus days on that bike and it was fine. A bit of
analysis shows that tires, seats, handle bar tape, all these things have a far greater affect on
ride than frame stiffness.

A bicycle is a system of components. THe compliance and dampening properties of the system are
determined by the combined properties of the system.

Interestingly, the frame has the least compliance and dampening of all the components so it is
rather silly to believe that the frame determines the ride qualities of the bike.

The place where frame stiffness is of importance is in out of plane stiffness, how the frame
deflects when you pedal.

My old Cannondale was the best in this area, never had a problem with the frame deflecting when I
decided to push the 110 inch gear up 8 or 10% grades.

The Sequioa looks to me to be a nice bike. I have a lugged steel Sequoia from 1984 which is still
giving me good service.

Jon Isaacs

 

[Archer]

Thanks for the comments; you brought up one other thing I liked about the Sequoiah, which is that it
has braze-ons for fenders and racks, which a lot of them don't.

In article <[email protected]>, [email protected] says...
> >The LeTour has 27 x 1.25, 85psi tires, and the Sequoiah has 700 x 26c tires, but I don't know the
> >pressure.
> >
> >Opinions, please?
>
> The Sequioa I saw recently looked like a reasonable bike, it had "normal reach" brakes rather than
> the standard short reach. Normal reach brakes allow you to use larger tires and fenders too,
> something I think is a good idea.

....

--
David Kerber An optimist says "Good morning, Lord." While a pessimist says "Good Lord,
it's morning".

Remove the ns_ from the address before e-mailing.

 

[Waxxer]

Gosh guys,

I am going to have to differ with you on material properties. I have Campy Record 10, same handle
bars, wheels and seat on my bikes, Colnago and Serotta). I notice the difference between steel and
titanium clearly. I have had a new C-dale and a friend of mine had the C-Dale team 4000 race bike.
We both hated the bikes. After 40 miles we were far more beaten up had we been riding steal.
Aesthetically, thin walled aluminum is tinny sounding creaks and groans, and is generally too stiff
for me. We dumped the C-Dales ASAP.

Aluminum is great for mountain bikes and TTs

"Jon Isaacs" <[email protected]> wrote in message
news:[email protected]...
> >The LeTour has 27 x 1.25, 85psi tires, and the Sequoiah has 700 x 26c tires, but I don't know the
> >pressure.
> >
> >Opinions, please?
>
> The Sequioa I saw recently looked like a reasonable bike, it had "normal
reach"
> brakes rather than the standard short reach. Normal reach brakes allow
you to
> use larger tires and fenders too, something I think is a good idea.
>
> The ride of the bike is determined by the tires and the tire pressure. I believe those old 1.25 x
> 27 inch tires at 85 psi probably provide a softer
ride
> than the 700C x 26 mm tires, but you can easily change those to a larger
tire.
>
>
> Just for a point of reference, I did have one of the original Cannondales,
the
> ones reputed to have that "beat em" ride. I did quite a few 100 mile plus
days
> on that bike and it was fine. A bit of analysis shows that tires, seats, handle bar tape, all
> these things have a far greater affect on ride than
frame
> stiffness.
>
> A bicycle is a system of components. THe compliance and dampening
properties
> of the system are determined by the combined properties of the system.
>
> Interestingly, the frame has the least compliance and dampening of all the components so it is
> rather silly to believe that the frame determines the
ride
> qualities of the bike.
>
> The place where frame stiffness is of importance is in out of plane
stiffness,
> how the frame deflects when you pedal.
>
> My old Cannondale was the best in this area, never had a problem with the
frame
> deflecting when I decided to push the 110 inch gear up 8 or 10% grades.
>
> The Sequioa looks to me to be a nice bike. I have a lugged steel Sequoia
from
> 1984 which is still giving me good service.
>
> Jon Isaacs

 

[Gary German]

"waxxer" <[email protected]> wrote in message news:[email protected]...
> Gosh guys,
>
> I am going to have to differ with you on material properties. I have Campy Record 10, same handle
> bars, wheels and seat on my bikes, Colnago and Serotta). I notice the difference between steel and
> titanium clearly. I
have
> had a new C-dale and a friend of mine had the C-Dale team 4000 race bike.
We
> both hated the bikes. After 40 miles we were far more beaten up had we
been
> riding steal. Aesthetically, thin walled aluminum is tinny sounding creaks and groans, and is
> generally too stiff for me. We dumped the C-Dales ASAP.
>
> Aluminum is great for mountain bikes and TTs
>

Agreed. My Trek 5200 (carbon fiber) is noticeably more comfortable than my old C-Dale R500,
particularly on longer rides.

>
> "Jon Isaacs" <[email protected]> wrote in message
> news:[email protected]...
> > >The LeTour has 27 x 1.25, 85psi tires, and the Sequoiah has 700 x 26c tires, but I don't know
> > >the pressure.
> > >
> > >Opinions, please?
> >
> > The Sequioa I saw recently looked like a reasonable bike, it had "normal
> reach"
> > brakes rather than the standard short reach. Normal reach brakes allow
> you to
> > use larger tires and fenders too, something I think is a good idea.
> >
> > The ride of the bike is determined by the tires and the tire pressure.
I
> > believe those old 1.25 x 27 inch tires at 85 psi probably provide a
softer
> ride
> > than the 700C x 26 mm tires, but you can easily change those to a larger
> tire.
> >
> >
> > Just for a point of reference, I did have one of the original
Cannondales,
> the
> > ones reputed to have that "beat em" ride. I did quite a few 100 mile
plus
> days
> > on that bike and it was fine. A bit of analysis shows that tires,
seats,
> > handle bar tape, all these things have a far greater affect on ride than
> frame
> > stiffness.
> >
> > A bicycle is a system of components. THe compliance and dampening
> properties
> > of the system are determined by the combined properties of the system.
> >
> > Interestingly, the frame has the least compliance and dampening of all
the
> > components so it is rather silly to believe that the frame determines
the
> ride
> > qualities of the bike.
> >
> > The place where frame stiffness is of importance is in out of plane
> stiffness,
> > how the frame deflects when you pedal.
> >
> > My old Cannondale was the best in this area, never had a problem with
the
> frame
> > deflecting when I decided to push the 110 inch gear up 8 or 10% grades.
> >
> > The Sequioa looks to me to be a nice bike. I have a lugged steel
Sequoia
> from
> > 1984 which is still giving me good service.
> >
> > Jon Isaacs

 

[David L. Johnso]

On Thu, 13 Mar 2003 12:46:40 -0500, archer wrote:

> I _know_ there's going to be a huge difference there. My LeTour is over 30 lbs, with steel rims,
> so it isn't exactly a drag racer coming off the line. The lightness will be nice, but durability
> and a reasonably comfortable ride are more important to me (not to the point of going to a
> "comfort" bike, though; I still like to ride fast).

Most folks don't have much experience with steel rims any more. I remember when I put a pair of good
wheels on my old bike for the first time. The difference between steel rims and 1.25" tires, versus
tubulars, was amazing. You will also be able to stop in the rain, which is a nice extra.

But keep in mind that frame materials do not make as much difference as advertised. Geometry and
engineering, yes, those can matter, but let that be the decision rather than what the fork happens
to be made of. The "vibration damping" of carbon forks is way overblown. Those 26mm tires will damp
a whole lot more than the fork.

More of a concern than anything else is fit. If it don't fit, it will be misery to ride, no matter
what it is made from.

--

David L. Johnson

__o | As far as the laws of mathematics refer to reality, they are not _`\(,_ | certain, and as
far as they are certain, they do not refer to (_)/ (_) | reality. -- Albert Einstein

 

[Waxxer]

Good question. Since components are identical--including tires ( I run the highest pressure open
corsa cx). Additionally both road frames are the same size. So what does make the difference? Is it
possibly the Bars--nope they are both Easton ec90s. Are the geometry's different--you bet. 72
degrees for seat tube angle verses 74.5 degrees. You would think that the steeper seat tube angle
would be more rigid. It is not because the chain stays and seat stays visibly flex. This is due to
the wonderful properties of titanium. These flexes known as cycles will go on forever without damage
to the material. This is my Serotta. I love it for century rides and all day in the saddle rides. It
is smooth yet gives up very little in lateral flex. So geometry and material makes a huge difference
in my mind. If it were aluminum it would have broken by now. Take an aluminum can and bend it back
and forth. It fails quickly. Take a steel can and will survive 3 times the number of cycles.

The Colnago on the other hand is so tight and springy it feels unreal. If I hit the worst of bumps,
it rolls through and snaps back as if it were thinking. You can feel the frame flex and respond
without the kind of springy effect of the titanium. The Serotta is like the Mercedes and the
Colnago--do I need to say more?

My Cannodale would literally pound my hands, shoulders and ass relentlessly. It was simply brutal.
When I came across road irregularities I would grimace knowing it was going to HURT!

May be my pain threshold is low. What I do know is that when I go out for a high speed game of tag;
the Colnago is preferred. I can do the same on the Serotta. I can ride it very aggressively, but I
prefer the comfort of titanium on really long rides. You simply do not fatigue as fast. Good carbon
fiber can also alleviate a lot of vibration and road fatigue.

"Jon Isaacs" <[email protected]> wrote in message
news:[email protected]...
> >I am going to have to differ with you on material properties. I have
Campy
> >Record 10, same handle bars, wheels and seat on my bikes, Colnago and Serotta). I notice the
> >difference between steel and titanium clearly.
>
> So exactly what did you do to determine that the differences were due to
the
> frame material and that indeed the differences were real?
>
> Jon Isaacs

 

[Frank Krygowski]

waxxer wrote:
>
> Good question. Since components are identical--including tires ( I run the highest pressure open
> corsa cx). Additionally both road frames are the same size. So what does make the difference? Is
> it possibly the Bars--nope they are both Easton ec90s. Are the geometry's different--you bet. 72
> degrees for seat tube angle verses 74.5 degrees. You would think that the steeper seat tube angle
> would be more rigid. It is not because the chain stays and seat stays visibly flex. This is due to
> the wonderful properties of titanium. These flexes known as cycles will go on forever without
> damage to the material. This is my Serotta. I love it for century rides and all day in the saddle
> rides. It is smooth yet gives up very little in lateral flex. So geometry and material makes a
> huge difference in my mind. If it were aluminum it would have broken by now. Take an aluminum can
> and bend it back and forth. It fails quickly. Take a steel can and will survive 3 times the number
> of cycles.
>
> The Colnago on the other hand is so tight and springy it feels unreal. If I hit the worst of
> bumps, it rolls through and snaps back as if it were thinking. You can feel the frame flex and
> respond without the kind of springy effect of the titanium. The Serotta is like the Mercedes and
> the Colnago--do I need to say more?
>
> My Cannodale would literally pound my hands, shoulders and ass relentlessly. It was simply brutal.
> When I came across road irregularities I would grimace knowing it was going to HURT!
>
> May be my pain threshold is low. What I do know is that when I go out for a high speed game of
> tag; the Colnago is preferred. I can do the same on the Serotta. I can ride it very aggressively,
> but I prefer the comfort of titanium on really long rides. You simply do not fatigue as fast. Good
> carbon fiber can also alleviate a lot of vibration and road fatigue.

I do most of my riding on a Cannondale, and in my experience, it's an _extremely_ comfortable bike.
Personally, I think you're swallowing a load of advertising claptrap, and letting it convince you
of what you feel. I think if you wrapped the bikes' frames in paper, you wouldn't be able to tell
them apart.

As Jon says, this stuff is quantifiable. It can be calculated and measured. It's silly to pretend
the 0.003" difference in vertical frame flex (if that) can be detected when your tires are
deflecting perhaps 50 times more... not to mention your saddle, fork, handlebar, seatpost, spokes,
and so on.

We had a guy who was a cat.2 racer graduate from the materials engineering program at our school. He
went to work for one of the biggest titanium producers in the country, and his job was essentially
to promote applications for titanium. But he said he completely disagreed with using titanium in a
bike frame. Its attributes are not what you need in a bike frame, and not worth the detriments.

Of course, Buycycling magazine has a different opinion. But those are the guys that can detect the
difference in ride between a red bike and an identical blue one! Almost makes you think their
opinions are governed more by ad revenue than by engineering. ;-)

--
Frank Krygowski [email protected]

 

[Benjamin Lewis]

Frank Krygowski wrote:

> Of course, Buycycling magazine has a different opinion. But those are the guys that can detect the
> difference in ride between a red bike and an identical blue one!

Now wait just a gol-danged minute there, Frank. Everyone knows that a red bike is faster, all other
things being equal. The same is true with sports cars. What are you trying to pull here, anyway?

--
Benjamin Lewis

A small, but vocal, contingent even argues that tin is superior, but they are held by most to be the
lunatic fringe of Foil Deflector Beanie science.

 

[Waxxer]

"Jon Isaacs" <[email protected]> wrote in message
news:[email protected]...
> > This is due to the wonderful properties of titanium. These flexes known as cycles will go on
> > forever without damage to the material.
>
> Well, you might look those numbers up for aluminum. If you do, you would discover that at a stress
> level of about 1/3 UTS (ultimate tensile
stress),
> most aluminums have a fatigue life of about half a billion cycles. To
reach
> this number you would have to ride 24 hours a day at 60 rpm for about 15
years
> and at an exertion level such that 3 times the effort would bend the
frame.

As aresearcher you reasoning is not what I would expect. Think of it in application and why does
Cannondale now limit their warranties and warn about stress fractures.

In the lab properties such as UTS are useful to help identify matrerials properties but that is a
long way from design application. A bulk head in a aircraft is very different tan the tubing used
in cycles. If titanium were cost effect and as readliy available what would be used more
prominently in aircraft.
>
> >So geometry and material makes a huge difference in my mind. If it were aluminum it would have
> >broken by now. Take an aluminum can and bend it
back
> >and forth. It fails quickly. Take a steel can and will survive 3 times
the
> >number of cycles.
>
> I happen to be a researcher in the field of materials science.
>
> The wonderful properties of titanium are similiarly wonderful for aluminum
and
> steel.
>
Too general so are the properties depleted uranium and tantelum

> What you have said is that you believe that a different bicycles have
different
> ride characteristics and comfort levels and that indeed these two bikes
are
> made from different materials.
>
> However I see no real support for the contention that it is indeed the
frame
> material that is responsible for this difference.
>
> Consider this: The seat stays are in compression. The deflection of the
seat
> stay under a 200lb load is on the order of 0.003inches, the thickness of a human hair. Now push on
> the seat and notice the deflection.
>
Not true given the shape of the tube and geometry. It can be seen with the naked eye.

> Changing the clamping point on the seat rails can have more effect on the compliance of the
> bicycle as a system that the frame itself has.
>
Seats and rails are the same

> So, it is nice to write poetry about the beautiful ride of a frame but the source of the
> differences in ride is found somewhere other than in the
material
> choice.
>
> jon isaacs

 

[Mike Jacoubowsk]

> That's silly. There's no difference in "frame comfort", it's all in your
head.
> I have a Cannondale (your worst-case) and I have an old Schwinn LeTour
(picked
> up at a swap meet 2 years ago), there's no difference in "frame comfort".

I know it's the politically-correct thing to stay out of such discussions, but...

There may not be a measurable difference in what somebody regards as "comfort" but there can be
marked differences in "feel" between frames of different materials & construction. This difference
in feel shows itself primarily in the way they do, or do not, carry a tune. Frames sound very
different when riding over smooth and not-so-smooth roads, and I think this
psychoacoustical (is there such a word?) effect has a great deal to do with how one
perceives the ride.

I will also maintain, based upon many tens of thousands of miles of riding experience, that I have
never owned a more comfortable bike than my OCLV carbon Trek. It is, quite simply, a whole lot less
"buzzy" over grainy road surfaces. I don't feel nearly as fatigued on a long ride as I used to, and
the comparable bikes all had virtually identical geometry and tire size. Could be that the
different wheels account for the difference, but I doubt it, since some of the wheels I've used
over the past few years have been rather deep in cross section, which presumably adds stiffness to
the ride (although the tire remains, obviously, the primary contributor to comfort, or lack
thereof, in that regard).

My other bikes have been steel and aluminum, and I still spend a fair amount of time on a classic
1973 Cinelli (it's my "rain bike" these days), so it's not as if I have nothing upon which to make
comparisons.

Please note, however, that the material is just one aspect of the equation, and one could build a
crappy bike out of carbon and a wonderful bike out of steel, and vice versa.

And, as always, consider everything I say to be 100% biased and suspect, since I make a living
selling OCLV TREKs.

--Mike-- Chain Reaction Bicycles http://www.ChainReaction.com

"Peter Cole" <[email protected]> wrote in message
news:TK4ca.77709$S_4.53089@rwcrnsc53...
> "B. Sanders" <[email protected]> wrote in message
> news:[email protected]...
> > "archer" <ns_archer1960@ns_hotmail.com> wrote in message
> > news:[email protected]...
> > > I know Aluminum frames have had a reputation (deserved or not) of
being
> > > stiff, and I'm wondering if that's still true, with the different
alloys
> > > they use now. My current bike is a 20+ year old steel-framed Schwinn LeTour (a.k.a LeTank).
> >
> > Aluminum has come a long way. My Klein Attitude (mountain hardtail)
feels
> > perfect - stiff, light; but doesn't beat me up like my old Cannondale
used
> > to. With aluminum, it's all about the engineering.
>
> That's silly. There's no difference in "frame comfort", it's all in your
head.
> I have a Cannondale (your worst-case) and I have an old Schwinn LeTour
(picked
> up at a swap meet 2 years ago), there's no difference in "frame comfort".

 

[Mike S.]

"Jon Isaacs" <[email protected]> wrote in message
news:[email protected]...
> > This is due to the wonderful properties of titanium. These flexes known as cycles will go on
> > forever without damage to the material.
>
> Well, you might look those numbers up for aluminum. If you do, you would discover that at a stress
> level of about 1/3 UTS (ultimate tensile
stress),
> most aluminums have a fatigue life of about half a billion cycles. To
reach
> this number you would have to ride 24 hours a day at 60 rpm for about 15
years
> and at an exertion level such that 3 times the effort would bend the
frame.
>
> >So geometry and material makes a huge difference in my mind. If it were aluminum it would have
> >broken by now. Take an aluminum can and bend it
back
> >and forth. It fails quickly. Take a steel can and will survive 3 times
the
> >number of cycles.
>
> I happen to be a researcher in the field of materials science.
>
> The wonderful properties of titanium are similiarly wonderful for aluminum
and
> steel.
>
> What you have said is that you believe that a different bicycles have
different
> ride characteristics and comfort levels and that indeed these two bikes
are
> made from different materials.
>
> However I see no real support for the contention that it is indeed the
frame
> material that is responsible for this difference.
>
> Consider this: The seat stays are in compression. The deflection of the
seat
> stay under a 200lb load is on the order of 0.003inches, the thickness of a human hair. Now push on
> the seat and notice the deflection.
>
Are you sure it is the compression that is determining the ride?? Could it perhaps be something
else? Like lateral flex, or the properties of the materials themselves: vibration damping, etc.?

If there weren't a difference SOMEWHERE, we'd all still be riding SL/SP.

Mike

> Changing the clamping point on the seat rails can have more effect on the compliance of the
> bicycle as a system that the frame itself has.
>
> So, it is nice to write poetry about the beautiful ride of a frame but the source of the
> differences in ride is found somewhere other than in the
material
> choice.

>
> jon isaacs

 

[Mike S.]

"Mike Jacoubowsky" <[email protected]> wrote in message
news:[email protected]...
> > That's silly. There's no difference in "frame comfort", it's all in your
> head.
> > I have a Cannondale (your worst-case) and I have an old Schwinn LeTour
> (picked
> > up at a swap meet 2 years ago), there's no difference in "frame
comfort".
>
> I know it's the politically-correct thing to stay out of such discussions, but...
>
> There may not be a measurable difference in what somebody regards as "comfort" but there can be
> marked differences in "feel" between frames of different materials & construction. This difference
> in feel shows itself primarily in the way they do, or do not, carry a tune. Frames sound very
> different when riding over smooth and not-so-smooth roads, and I think
this
> psychoacoustical (is there such a word?) effect has a great deal to do
with
> how one perceives the ride.
>
> I will also maintain, based upon many tens of thousands of miles of riding experience, that I have
> never owned a more comfortable bike than my OCLV carbon Trek. It is, quite simply, a whole lot
> less "buzzy" over grainy
road
> surfaces. I don't feel nearly as fatigued on a long ride as I used to,
and
> the comparable bikes all had virtually identical geometry and tire size. Could be that the
> different wheels account for the difference, but I doubt it, since some of the wheels I've used
> over the past few years have been rather deep in cross section, which presumably adds stiffness to
> the ride (although the tire remains, obviously, the primary contributor to comfort, or lack
> thereof, in that regard).
>
> My other bikes have been steel and aluminum, and I still spend a fair
amount
> of time on a classic 1973 Cinelli (it's my "rain bike" these days), so
it's
> not as if I have nothing upon which to make comparisons.
>
> Please note, however, that the material is just one aspect of the
equation,
> and one could build a crappy bike out of carbon and a wonderful bike out
of
> steel, and vice versa.
>
> And, as always, consider everything I say to be 100% biased and suspect, since I make a living
> selling OCLV TREKs.
>
> --Mike-- Chain Reaction Bicycles http://www.ChainReaction.com

I can vouch for the bad ride of the original C'dale crit frames. I used to be OK riding one up to
about 90min, but after that, things started to hurt. I bought my first "real" bike, a PDM SLX
Concorde shortly after I bought the C-dale. First ride, no sore crotch, no sore back, same stiffness
in the frame.

I was riding my Gilmour a few weeks ago (853 steel) before I decided that it didn't fit (knees too
far behind bb). Nice "zingy" ride. Very lively feel. Bought a Bontrager Road Lite (steel) and built
it with the components off the Gilmour. Completely different feel. Not quite as lively, but smoother
overall. Could be that the Bontrager is older, who knows. Same wheels and tires on both, both pumped
up with the same Silca pump to the same red line, same roads.

My favorite-riding bike off all time was a TIG welded SL Battaglin that I picked up as an
afterthought when Perf. was blowing them out. Man, talk about all day comfort! I could sit on that
thing and ride, and ride, and... Not too great in a sprint because it was way flexy when I was
hammering on
it. I could look down at the bb when I was sprinting, and it was moving back and forth across an
arc of at least 1-2cm!

My M4 S-Works rides a little harsher than both the steel bikes, but not very badly at all.

I had a Performance Ti Mtn frame that was another noodle. Climbed like a champ because the
chainstays flexed enough to keep the rear wheel digging in even when going over bumps and roots.
When hammering on it, the bb moved around so much that the chain would rub on the f.der in
almost any gear!

I got to thinking (as I was out on a 2 hour training ride) about what makes a frame ride well. It
can't be overall stiffness. That number really doesn't tell me anything about HOW the frame reacts
to the small bumps that are constantly being transmitted to it. I'd be willing to bet that the
perception of how a frame rides is based on how it deals with the small, high frequency bumps rather
than the big hits.

I would be willing to bet that the "best riding" frames deal well with the small bumps. I was
thinking about this as I was riding over some chip and seal-ish road. A tube of steel is going to be
smaller in diameter than a tube of Ti, which is going to be smaller than a tube of AL for a given
stiffness. Right?

Conversly, a tube of steel is going to bend slightly if acted on by a small load, slightly less for
Ti, and slightly less for AL. That should be the difference in ride quality, not overall stiffness.

Now I'm no engineer, so someone else's gonna have to figure out if I'm talking out my ass on
this one, but it makes sense if you stop and think about it. Strain guages, and 3d modelling of
what happens when a frame is flexed are probably going to be required, things I don't have any
access to...

Best bet: ride steel, ride AL, ride Ti, and ride carbon. Then tell me that there's no difference in
frame feel... Someone out there has to have enough friends with one of each to be able to transfer
wheels and saddles around to be able to make the test as neutral as possible.

Mike


>
> "Peter Cole" <[email protected]> wrote in message
> news:TK4ca.77709$S_4.53089@rwcrnsc53...
> > "B. Sanders" <[email protected]> wrote in message
> > news:[email protected]...
> > > "archer" <ns_archer1960@ns_hotmail.com> wrote in message
> > > news:[email protected]...
> > > > I know Aluminum frames have had a reputation (deserved or not) of
> being
> > > > stiff, and I'm wondering if that's still true, with the different
> alloys
> > > > they use now. My current bike is a 20+ year old steel-framed
Schwinn
> > > > LeTour (a.k.a LeTank).
> > >
> > > Aluminum has come a long way. My Klein Attitude (mountain hardtail)
> feels
> > > perfect - stiff, light; but doesn't beat me up like my old Cannondale
> used
> > > to. With aluminum, it's all about the engineering.
> >
> > That's silly. There's no difference in "frame comfort", it's all in your
> head.
> > I have a Cannondale (your worst-case) and I have an old Schwinn LeTour
> (picked
> > up at a swap meet 2 years ago), there's no difference in "frame
comfort".
> >
>

 

[B. Sanders]

"Peter Cole" <[email protected]> wrote in message
news:TK4ca.77709$S_4.53089@rwcrnsc53...
> "B. Sanders" <[email protected]> wrote in message
> news:[email protected]...
> > "archer" <ns_archer1960@ns_hotmail.com> wrote in message
> > news:[email protected]...
> > > I know Aluminum frames have had a reputation (deserved or not) of
being
> > > stiff, and I'm wondering if that's still true, with the different
alloys
> > > they use now. My current bike is a 20+ year old steel-framed Schwinn LeTour (a.k.a LeTank).
> >
> > Aluminum has come a long way. My Klein Attitude (mountain hardtail)
feels
> > perfect - stiff, light; but doesn't beat me up like my old Cannondale
used
> > to. With aluminum, it's all about the engineering.
>
> That's silly. There's no difference in "frame comfort", it's all in your
head.

No, actually it's in my butt and my hands. There *is* a difference. I don't have to prove it, or
explain it, I only have to observe it; and observe I have.

I've heard all of the eggheads weigh-in on this. My butt, hands and ankles tell me that they're
wrong. That's all I need to know.

-Barry

 

[B. Sanders]

"waxxer" <[email protected]> wrote in message news:[email protected]...
> Gosh guys,
>
> I am going to have to differ with you on material properties. I have Campy Record 10, same handle
> bars, wheels and seat on my bikes, Colnago and Serotta). I notice the difference between steel and
> titanium clearly. I
have
> had a new C-dale and a friend of mine had the C-Dale team 4000 race bike.
We
> both hated the bikes. After 40 miles we were far more beaten up had we
been
> riding steal. Aesthetically, thin walled aluminum is tinny sounding creaks and groans, and is
> generally too stiff for me. We dumped the C-Dales ASAP.

Gonna have to agree here. I've owned several different high-end bikes made from each major material:
carbon, titanium, aluminum and steel. All of the Ti bike (Merlin, Kona and WTB) were very
comfortable to ride. Most of the aluminum bikes (especially the 4 Cannondales) were very stiff - I
felt bruised and shaken after riding them. However, the 3 Klein's that I've owned were much more
comfortable. Steel bikes (I've owned at least 15 of them) really do have a marvelous ride quality,
unlike any other material. Carbon is probably my favorite, with the best balance of ride properties,
and is very quick.

Those are my observations. I'm not partial to any material, and I've spent enough time on each type
of bike and have owned and ridden enough of them to have a decent sample size. People who say there
is no difference between frame materials are simply wrong.

-Barry

> Aluminum is great for mountain bikes and TTs
>
>
> "Jon Isaacs" <[email protected]> wrote in message
> news:[email protected]...
> > >The LeTour has 27 x 1.25, 85psi tires, and the Sequoiah has 700 x 26c tires, but I don't know
> > >the pressure.
> > >
> > >Opinions, please?
> >
> > The Sequioa I saw recently looked like a reasonable bike, it had "normal
> reach"
> > brakes rather than the standard short reach. Normal reach brakes allow
> you to
> > use larger tires and fenders too, something I think is a good idea.
> >
> > The ride of the bike is determined by the tires and the tire pressure.
I
> > believe those old 1.25 x 27 inch tires at 85 psi probably provide a
softer
> ride
> > than the 700C x 26 mm tires, but you can easily change those to a larger
> tire.
> >
> >
> > Just for a point of reference, I did have one of the original
Cannondales,
> the
> > ones reputed to have that "beat em" ride. I did quite a few 100 mile
plus
> days
> > on that bike and it was fine. A bit of analysis shows that tires,
seats,
> > handle bar tape, all these things have a far greater affect on ride than
> frame
> > stiffness.
> >
> > A bicycle is a system of components. THe compliance and dampening
> properties
> > of the system are determined by the combined properties of the system.
> >
> > Interestingly, the frame has the least compliance and dampening of all
the
> > components so it is rather silly to believe that the frame determines
the
> ride
> > qualities of the bike.
> >
> > The place where frame stiffness is of importance is in out of plane
> stiffness,
> > how the frame deflects when you pedal.
> >
> > My old Cannondale was the best in this area, never had a problem with
the
> frame
> > deflecting when I decided to push the 110 inch gear up 8 or 10% grades.
> >
> > The Sequioa looks to me to be a nice bike. I have a lugged steel
Sequoia
> from
> > 1984 which is still giving me good service.
> >
> > Jon Isaacs

 

[Mike S.]

"B. Sanders" <[email protected]> wrote in message
news:[email protected]...
> "Peter Cole" <[email protected]> wrote in message
> news:TK4ca.77709$S_4.53089@rwcrnsc53...
> > "B. Sanders" <[email protected]> wrote in message
> > news:[email protected]...
> > > "archer" <ns_archer1960@ns_hotmail.com> wrote in message
> > > news:[email protected]...
> > > > I know Aluminum frames have had a reputation (deserved or not) of
> being
> > > > stiff, and I'm wondering if that's still true, with the different
> alloys
> > > > they use now. My current bike is a 20+ year old steel-framed
Schwinn
> > > > LeTour (a.k.a LeTank).
> > >
> > > Aluminum has come a long way. My Klein Attitude (mountain hardtail)
> feels
> > > perfect - stiff, light; but doesn't beat me up like my old Cannondale
> used
> > > to. With aluminum, it's all about the engineering.
> >
> > That's silly. There's no difference in "frame comfort", it's all in your
> head.
>
> No, actually it's in my butt and my hands. There *is* a difference. I don't have to prove it, or
> explain it, I only have to observe it; and observe I have.
>
> I've heard all of the eggheads weigh-in on this. My butt, hands and
ankles
> tell me that they're wrong. That's all I need to know.
>
> -Barry
>
>
I read a quote the other day that I'm going to have to paraphrase because I didn't write it down: in
theory, there is no difference between theory and practice. In practice there is.

Could be that the engineers are looking at the wrong things. Could be a lot of things, from faulty
assumptions, to bad test criteria, I don't know. I do know that there are differences between bikes,
no matter what anyone tries to tell me. They may be subtle, hard to quantify, but they're there.

Mike