Critique requested - Cycling Mob: Road Cycling, Mountain Biking and More

10-10-2003, 01:08 PM

My co-worker has been hounding me to buy a Seven bike. Please critique
this little essay he sent me:

---

I know you're sick of hearing about ti bike company comparisons, but
here goes.
I know that you're into the local idea, and if you were considering a
custom steel frame, I'd say why not? But there are still massive
qualitative differences b/w Ti manufacturers' products, and you need,
therefore, to immerse yourself more into the research process. And,
what's more fun than that anyway?!

There are three primary differences between Seven and the other guys:
1. Seven uses butted tubing, and they have the longest experience
working w/ butten ti (a difficult thing to find in frames).
2. Seven uses a space industry grade 3Al-2.5V ti instead a sports or
commercial grade, and also instead of 6AL-4V (a lower quality alloy
for frames), which is what you'll find in some of the Moots frame
sets.
3. Seven doesn't do final surface treatments (peening or texturizing),
as this can cause stress risers and hides sloppy welds (like linings
in Gore-Tex jackets).

Seven allows for a truly custom frame with the axiom not just limiting
a customer to tubelengths and handling characteristics but also tube
dimensions and butt placement.
They also use the best domestically sourced ti tubes available and as
far as i know, they are the only ones to do so (though, i think the
real world implications of this fact are probably non-existant).
welds are clean, finish is luxurious.
handling is a little risky to comment on as they are custom bikes.
mine handles like a dream though.
ride characteristics also vary with each frame... mine is on the
steel-like side.

for the money, Sevens are a terrific value. keep in mind that
non-custom Merlins made with comparable design considerations (ala
butted tubes) cost just as much as fully custom sevens do. Litespeeds,
anything other than the arenberg and tuscany will cost a pretty penny
too. Moots (best welds!) and Ibis probably are my favorite Ti bikes
after Seven and both only offer straight-gauge tubesets at a price
comparable to Seven's Alaris model. With Moots, custom will cost extra
too.
also on the side of value is the longevity of Ti. most people complain
about the cost of Seven's, but in reality, they are not that bad
compared with other truly high performance bicycles.
plus, why would you want a couple of thousand dollars when you could
have a great bicycle instead.

one gripe is that i asked for the bike to be set-up with DT shifter
bosses - not because i like the way the look or think they are more
accessible than STI braze-ons, but because i was actually planning to
use DT shifters! the boss was inserted so far up the downtube that not
only did it look funny, but my fingers would get caught in the brake
cable housing when i reached for the left shifter. i can theorize that
the reason was to place the boss at the thickest part of the butt, but
they could have run the butt longer to lower the boss.
another gripe is the ST H20 braze on. it's too high at midway down the
seattube. it looks odd, and i suppose it raises the bike's center of
gravity. this, i admit is getting nit-picky. i only wish that i had
thought about both of these issues (shifter boss & H20 boss) and told
Seven _exactly_ where i wanted them placed.

Overall rating reflects that this is indeed a solid bike and as good
if not better than any currently available. Still, i don't consider it
one of the truly great bikes of all time. Given the chance to buy it
again though, i'd do it without a second thought.

Types of Ti
In addition to unalloyed titanium, which is called commercially pure
or CP, there are two alloys commonly used in the cycling industry
today: 3AL-2.5V and 6AL-4V.

3AL-2.5V
3-2.5 titanium is an alloy consisting of 3% aluminum, 2.5% vanadium,
and 94.5% pure titanium. The properties critical to bicycle tubing are
best served by a high quality 3-2.5 seamless tube. Excellent fatigue
life, property consistency, formability, and corrosion resistance are
but a few of the reasons 3-2.5 is still the premier frame material.

In the U.S., bicycle frames are commonly manufactured using 3-2.5
certified to either an ASTM B-338 or a sports grade specification.
ASTM B-338 meets all Aerospace Material Specifications for hydraulic
tubing. Sports grade, certified according to a less stringent set of
chemical and mechanical specifications, is typically less expensive.

Some builders may use surplus material or "scrap", which meets neither
aerospace nor sports grade specifications. Certification is not
available for scrap, making it impossible to determine whether the
material is of inferior quality.

6AL-4V
An alloy of 6% aluminum, 4% vanadium, and 90% titanium, 6-4 titanium
offers some very favorable raw material properties, which is why Seven
uses it to fabricate dropouts and other frame parts. One of the
properties that makes 6-4 an optimal material for dropouts is its
toughness. But this toughness also makes it unattractive as a material
from which to make tubing. Applying the techniques used to draw 3-2.5
tubing to 6-4 tubing costs more and wears tooling very quickly. In
addition, tube wall consistency, concentricity, and finish
quality-both inside and outside-are limited. At the time of this
printing, no U.S. mill offers seamless 6-4 tubing. However, some do
offer 6-4 seamed, or welded, tubing.

Two major issues prevent Seven Cycles from favoring this method of
tube manufacture. First, seamed tubing is fabricated by rolling 6-4
sheet into a tube shape while simultaneously welding the seam that is
created in the rolling process. The result is a tube that has a welded
seam-a potential failure point-along its length. This seam acts as
both a hard point and a stress riser since the weld bead is thicker
than the tube itself and the weld creates an inconsistency in the
tube.

Second, 6-4 sheet is designed to be used as a sheet, not as a tube. If
it is formed into a tube, its grain structure can lead to premature
tube failure. Indeed, a 6-4 tube will fail through fatigue cycling
(repeated flexing) before it should, and independent fatigue tests
show that tubing made from 6-4 sheet does not have the fatigue life of
a properly drawn 3-2.5 tube.

In addition, an examination of some other high-tech industries that
depend on high strength alloys like 3-2.5 and 6-4 reveals that none
use 6-4 small diameter tubing, primarily for the reasons mentioned
above. Consultation with titanium mills over the past decade tells us
that seamless 6-4 is not on the near horizon.

CP
A small number of titanium frame builders incorporate Commercially
Pure (CP) titanium into their frames. CP has, at best, half the
strength of 3-2.5. A CP frame must be made heavier than an equivalent
3-2.5 frame in order to have comparable strength. Even most steels
used in high quality frames have higher strength than CP. The overall
quality of CP tubing is lower because it is typically used in low-cost
applications-not bicycle building. CP is used mainly in industrial
applications when corrosion resistance is most important.

10-10-2003, 01:21 PM

> My co-worker has been hounding me to buy a Seven bike.

Why should he hound you? What's in it for him?

Dave

10-10-2003, 02:30 PM

In article <[Only registered and activated users can see links. ] >,
Claire Petersky <[Only registered and activated users can see links. ]> wrote:
>My co-worker has been hounding me to buy a Seven bike. Please critique
>this little essay he sent me:

This is the hype you get from many boutique builders who work with
titanium, they are desperate to differentiate their products because
when it's between your legs it's almost impossible, and most of
them don't use paint as a differentiator. I would expect high
quality materials and excellent welding from Seven. But many less
expensive bikes are well made and OK for you as long as the bike
suits you in fit and design.

There are low quality titanium bikes to be avoided. But there is a
very large field of good choices out there and most well-known
custom ti builders do good work.

I agree with the other posters on 6-4 titanium - as a tubing it
is reserved for the most expensive frames, I wouldn't call it
inferior but I wouldn't consider paying for it either.

"for the money" Sevens are very expensive and if you don't buy
the brand image, hard to justify. I would only buy into it
if there was some emotional attraction, but for me Seven has
a kind of East coast triathlete chic to it for some reason. :-)

Even in steel Seven is above the cost of some decent custom ti
builders.

I think a custom bike worth buying should have some emotional appeal
for the buyer. If a forest green lugged steel bike with curly stays
is what floats your boat, who's to say no?

--Paul

10-10-2003, 03:09 PM

Claire: Sevens are great bikes, no question, but the majority of people
benefit from a "custom" bike primarily because they feel it's cool to have
something unique. A very, very small subset of cyclists actually require
something different from the norm of currently-available fit & geometries.
Now, there's nothing wrong with wanting something unique, you just have to
recognize that you're paying for that desire.

And, of course, I'd love to see you try out a TREK OCLV and see what you
thought of the ride! :>)

--Mike--
Chain Reaction Bicycles
[Only registered and activated users can see links. ]

"Claire Petersky" <[Only registered and activated users can see links. ]> wrote in message
news:1a88718b.0310101208.2032a80f@posting.google.c om...
> My co-worker has been hounding me to buy a Seven bike. Please critique
> this little essay he sent me:
>
> ---
>
> I know you're sick of hearing about ti bike company comparisons, but
> here goes.
> I know that you're into the local idea, and if you were considering a
> custom steel frame, I'd say why not? But there are still massive
> qualitative differences b/w Ti manufacturers' products, and you need,
> therefore, to immerse yourself more into the research process. And,
> what's more fun than that anyway?!
>
> There are three primary differences between Seven and the other guys:
> 1. Seven uses butted tubing, and they have the longest experience
> working w/ butten ti (a difficult thing to find in frames).
> 2. Seven uses a space industry grade 3Al-2.5V ti instead a sports or
> commercial grade, and also instead of 6AL-4V (a lower quality alloy
> for frames), which is what you'll find in some of the Moots frame
> sets.
> 3. Seven doesn't do final surface treatments (peening or texturizing),
> as this can cause stress risers and hides sloppy welds (like linings
> in Gore-Tex jackets).
>
> Seven allows for a truly custom frame with the axiom not just limiting
> a customer to tubelengths and handling characteristics but also tube
> dimensions and butt placement.
> They also use the best domestically sourced ti tubes available and as
> far as i know, they are the only ones to do so (though, i think the
> real world implications of this fact are probably non-existant).
> welds are clean, finish is luxurious.
> handling is a little risky to comment on as they are custom bikes.
> mine handles like a dream though.
> ride characteristics also vary with each frame... mine is on the
> steel-like side.
>
> for the money, Sevens are a terrific value. keep in mind that
> non-custom Merlins made with comparable design considerations (ala
> butted tubes) cost just as much as fully custom sevens do. Litespeeds,
> anything other than the arenberg and tuscany will cost a pretty penny
> too. Moots (best welds!) and Ibis probably are my favorite Ti bikes
> after Seven and both only offer straight-gauge tubesets at a price
> comparable to Seven's Alaris model. With Moots, custom will cost extra
> too.
> also on the side of value is the longevity of Ti. most people complain
> about the cost of Seven's, but in reality, they are not that bad
> compared with other truly high performance bicycles.
> plus, why would you want a couple of thousand dollars when you could
> have a great bicycle instead.
>
> one gripe is that i asked for the bike to be set-up with DT shifter
> bosses - not because i like the way the look or think they are more
> accessible than STI braze-ons, but because i was actually planning to
> use DT shifters! the boss was inserted so far up the downtube that not
> only did it look funny, but my fingers would get caught in the brake
> cable housing when i reached for the left shifter. i can theorize that
> the reason was to place the boss at the thickest part of the butt, but
> they could have run the butt longer to lower the boss.
> another gripe is the ST H20 braze on. it's too high at midway down the
> seattube. it looks odd, and i suppose it raises the bike's center of
> gravity. this, i admit is getting nit-picky. i only wish that i had
> thought about both of these issues (shifter boss & H20 boss) and told
> Seven _exactly_ where i wanted them placed.
>
> Overall rating reflects that this is indeed a solid bike and as good
> if not better than any currently available. Still, i don't consider it
> one of the truly great bikes of all time. Given the chance to buy it
> again though, i'd do it without a second thought.
>
> Types of Ti
> In addition to unalloyed titanium, which is called commercially pure
> or CP, there are two alloys commonly used in the cycling industry
> today: 3AL-2.5V and 6AL-4V.
>
> 3AL-2.5V
> 3-2.5 titanium is an alloy consisting of 3% aluminum, 2.5% vanadium,
> and 94.5% pure titanium. The properties critical to bicycle tubing are
> best served by a high quality 3-2.5 seamless tube. Excellent fatigue
> life, property consistency, formability, and corrosion resistance are
> but a few of the reasons 3-2.5 is still the premier frame material.
>
> In the U.S., bicycle frames are commonly manufactured using 3-2.5
> certified to either an ASTM B-338 or a sports grade specification.
> ASTM B-338 meets all Aerospace Material Specifications for hydraulic
> tubing. Sports grade, certified according to a less stringent set of
> chemical and mechanical specifications, is typically less expensive.
>
> Some builders may use surplus material or "scrap", which meets neither
> aerospace nor sports grade specifications. Certification is not
> available for scrap, making it impossible to determine whether the
> material is of inferior quality.
>
> 6AL-4V
> An alloy of 6% aluminum, 4% vanadium, and 90% titanium, 6-4 titanium
> offers some very favorable raw material properties, which is why Seven
> uses it to fabricate dropouts and other frame parts. One of the
> properties that makes 6-4 an optimal material for dropouts is its
> toughness. But this toughness also makes it unattractive as a material
> from which to make tubing. Applying the techniques used to draw 3-2.5
> tubing to 6-4 tubing costs more and wears tooling very quickly. In
> addition, tube wall consistency, concentricity, and finish
> quality-both inside and outside-are limited. At the time of this
> printing, no U.S. mill offers seamless 6-4 tubing. However, some do
> offer 6-4 seamed, or welded, tubing.
>
> Two major issues prevent Seven Cycles from favoring this method of
> tube manufacture. First, seamed tubing is fabricated by rolling 6-4
> sheet into a tube shape while simultaneously welding the seam that is
> created in the rolling process. The result is a tube that has a welded
> seam-a potential failure point-along its length. This seam acts as
> both a hard point and a stress riser since the weld bead is thicker
> than the tube itself and the weld creates an inconsistency in the
> tube.
>
> Second, 6-4 sheet is designed to be used as a sheet, not as a tube. If
> it is formed into a tube, its grain structure can lead to premature
> tube failure. Indeed, a 6-4 tube will fail through fatigue cycling
> (repeated flexing) before it should, and independent fatigue tests
> show that tubing made from 6-4 sheet does not have the fatigue life of
> a properly drawn 3-2.5 tube.
>
> In addition, an examination of some other high-tech industries that
> depend on high strength alloys like 3-2.5 and 6-4 reveals that none
> use 6-4 small diameter tubing, primarily for the reasons mentioned
> above. Consultation with titanium mills over the past decade tells us
> that seamless 6-4 is not on the near horizon.
>
> CP
> A small number of titanium frame builders incorporate Commercially
> Pure (CP) titanium into their frames. CP has, at best, half the
> strength of 3-2.5. A CP frame must be made heavier than an equivalent
> 3-2.5 frame in order to have comparable strength. Even most steels
> used in high quality frames have higher strength than CP. The overall
> quality of CP tubing is lower because it is typically used in low-cost
> applications-not bicycle building. CP is used mainly in industrial
> applications when corrosion resistance is most important.

10-10-2003, 03:32 PM

[Only registered and activated users can see links. ] (Claire Petersky) writes:

One thing I noticed about 6Al/3CV Ti frames is that in VeloNews (i
think), when they do the 15+ page guides to current PRO bicycles
available, the 6Al/3CV bikes always list significantly lower weights
than the 3Al/2.5CV frames.

- Don

10-10-2003, 03:45 PM

"Claire Petersky" <[Only registered and activated users can see links. ]> wrote in message
news:1a88718b.0310101208.2032a80f@posting.google.c om...
> My co-worker has been hounding me to buy a Seven bike. Please critique
> this little essay he sent me:
>
> ---
>
> I know you're sick of hearing about ti bike company comparisons, but
> here goes.
> I know that you're into the local idea, and if you were considering a
> custom steel frame, I'd say why not? But there are still massive
> qualitative differences b/w Ti manufacturers' products, and you need,
> therefore, to immerse yourself more into the research process. And,
> what's more fun than that anyway?!
>
> There are three primary differences between Seven and the other guys:
> 1. Seven uses butted tubing, and they have the longest experience
> working w/ butten ti (a difficult thing to find in frames).

Serotta has been doing ti for years and has led the Vanguard in ti. Seven
may have people from Serotta and Merlin who I believe have been around
longer.

> 2. Seven uses a space industry grade 3Al-2.5V ti instead a sports or
> commercial grade, and also instead of 6AL-4V (a lower quality alloy
> for frames), which is what you'll find in some of the Moots frame
> sets.

Serotta uses a much more sofisticated tube than the common space materials.

> 3. Seven doesn't do final surface treatments (peening or texturizing),
> as this can cause stress risers and hides sloppy welds (like linings
> in Gore-Tex jackets).

Some merit to this argument. However not in the application of bike frames
unless you score the material.
>
> Seven allows for a truly custom frame with the axiom not just limiting
> a customer to tubelengths and handling characteristics but also tube
> dimensions and butt placement.

Custom fitting is done by Serotta as well. What is more important is the
person doing the fitting for you. Seven probably uses the Serotta sizing
cycle like many others.

> They also use the best domestically sourced ti tubes available and as
> far as i know, they are the only ones to do so (though, i think the
> real world implications of this fact are probably non-existant).
> welds are clean, finish is luxurious.
> handling is a little risky to comment on as they are custom bikes.
> mine handles like a dream though.
> ride characteristics also vary with each frame... mine is on the
> steel-like side

Variation may occur to a little degree in different tube lengths. The
variation your friend describes sounds like the process is out of control or
materials are different.
>
> for the money, Sevens are a terrific value. keep in mind that
> non-custom Merlins made with comparable design considerations (ala
> butted tubes) cost just as much as fully custom sevens do. Litespeeds,
> anything other than the arenberg and tuscany will cost a pretty penny
> too. Moots (best welds!) and Ibis probably are my favorite Ti bikes
> after Seven and both only offer straight-gauge tubesets at a price
> comparable to Seven's Alaris model. With Moots, custom will cost extra
> too.

Moots, I like Moots. Lightspeed is mass produced by Trek or some other big
outfit. Is Ibis still in business?

> also on the side of value is the longevity of Ti. most people complain
> about the cost of Seven's, but in reality, they are not that bad
> compared with other truly high performance bicycles.
> plus, why would you want a couple of thousand dollars when you could
> have a great bicycle instead.

Sevens are just as indistinct as any vanilla ti tube. Serotta on the other
hand has tubes custom forged asymetrically to get consistent and repeatable
ride for the geometry of the bike.
>
> one gripe is that i asked for the bike to be set-up with DT shifter
> bosses - not because i like the way the look or think they are more
> accessible than STI braze-ons, but because i was actually planning to
> use DT shifters! the boss was inserted so far up the downtube that not
> only did it look funny, but my fingers would get caught in the brake
> cable housing when i reached for the left shifter. i can theorize that
> the reason was to place the boss at the thickest part of the butt, but
> they could have run the butt longer to lower the boss.
> another gripe is the ST H20 braze on. it's too high at midway down the
> seattube. it looks odd, and i suppose it raises the bike's center of
> gravity. this, i admit is getting nit-picky. i only wish that i had
> thought about both of these issues (shifter boss & H20 boss) and told
> Seven _exactly_ where i wanted them placed.
>
> Overall rating reflects that this is indeed a solid bike and as good
> if not better than any currently available. Still, i don't consider it
> one of the truly great bikes of all time. Given the chance to buy it
> again though, i'd do it without a second thought.

Personal preference is great but it is your money. Try a Serotta Legend or
Otrott with Carbon before you go with the fancy headbadge with good
engineering and the abiity to stick ti tubes together.
>
> Types of Ti
> In addition to unalloyed titanium, which is called commercially pure
> or CP, there are two alloys commonly used in the cycling industry
> today: 3AL-2.5V and 6AL-4V.
>
> 3AL-2.5V
> 3-2.5 titanium is an alloy consisting of 3% aluminum, 2.5% vanadium,
> and 94.5% pure titanium. The properties critical to bicycle tubing are
> best served by a high quality 3-2.5 seamless tube. Excellent fatigue
> life, property consistency, formability, and corrosion resistance are
> but a few of the reasons 3-2.5 is still the premier frame material.
>
> In the U.S., bicycle frames are commonly manufactured using 3-2.5
> certified to either an ASTM B-338 or a sports grade specification.
> ASTM B-338 meets all Aerospace Material Specifications for hydraulic
> tubing. Sports grade, certified according to a less stringent set of
> chemical and mechanical specifications, is typically less expensive.
>
> Some builders may use surplus material or "scrap", which meets neither
> aerospace nor sports grade specifications. Certification is not
> available for scrap, making it impossible to determine whether the
> material is of inferior quality.
>
> 6AL-4V
> An alloy of 6% aluminum, 4% vanadium, and 90% titanium, 6-4 titanium
> offers some very favorable raw material properties, which is why Seven
> uses it to fabricate dropouts and other frame parts. One of the
> properties that makes 6-4 an optimal material for dropouts is its
> toughness. But this toughness also makes it unattractive as a material
> from which to make tubing. Applying the techniques used to draw 3-2.5
> tubing to 6-4 tubing costs more and wears tooling very quickly. In
> addition, tube wall consistency, concentricity, and finish
> quality-both inside and outside-are limited. At the time of this
> printing, no U.S. mill offers seamless 6-4 tubing. However, some do
> offer 6-4 seamed, or welded, tubing.
>
> Two major issues prevent Seven Cycles from favoring this method of
> tube manufacture. First, seamed tubing is fabricated by rolling 6-4
> sheet into a tube shape while simultaneously welding the seam that is
> created in the rolling process. The result is a tube that has a welded
> seam-a potential failure point-along its length. This seam acts as
> both a hard point and a stress riser since the weld bead is thicker
> than the tube itself and the weld creates an inconsistency in the
> tube.
>
> Second, 6-4 sheet is designed to be used as a sheet, not as a tube. If
> it is formed into a tube, its grain structure can lead to premature
> tube failure. Indeed, a 6-4 tube will fail through fatigue cycling
> (repeated flexing) before it should, and independent fatigue tests
> show that tubing made from 6-4 sheet does not have the fatigue life of
> a properly drawn 3-2.5 tube.
>
> In addition, an examination of some other high-tech industries that
> depend on high strength alloys like 3-2.5 and 6-4 reveals that none
> use 6-4 small diameter tubing, primarily for the reasons mentioned
> above. Consultation with titanium mills over the past decade tells us
> that seamless 6-4 is not on the near horizon.
>
> CP
> A small number of titanium frame builders incorporate Commercially
> Pure (CP) titanium into their frames. CP has, at best, half the
> strength of 3-2.5. A CP frame must be made heavier than an equivalent
> 3-2.5 frame in order to have comparable strength. Even most steels
> used in high quality frames have higher strength than CP. The overall
> quality of CP tubing is lower because it is typically used in low-cost
> applications-not bicycle building. CP is used mainly in industrial
> applications when corrosion resistance is most important.

10-10-2003, 04:07 PM

On 10 Oct 2003 13:08:26 -0700, [Only registered and activated users can see links. ] (Claire Petersky)
wrote:

>for the money, Sevens are a terrific value.

Here's what to tell him -- just quote the section above and say "ha
ha, you're such a kidder. Now shut up."

JT
*******************************************
NB: reply-to address is munged

Visit [Only registered and activated users can see links. ]
*******************************************

10-10-2003, 05:35 PM

aside from all the marketing hype, i have the following technical comments:

> 1. Seven uses butted tubing, and they have the longest experience
> working w/ butten ti (a difficult thing to find in frames).

yes, butted is better, but 7 are not the only ones using it.

> 2. Seven uses a space industry grade 3Al-2.5V ti instead a sports or
> commercial grade, and also instead of 6AL-4V (a lower quality alloy
> for frames), which is what you'll find in some of the Moots frame
> sets.

incorrect. 6-4 is unquestionably the superior technical tubeset -
better specific modulus. but it's significanly more expensive and
therefore less profitable.

> 3. Seven doesn't do final surface treatments (peening or texturizing),

peening is good for fatigue.

> as this can cause stress risers

risers are typically helped by finishing, not hindered.

and hides sloppy welds (like linings
> in Gore-Tex jackets).

the primary determinant of strength in a ti weld is oxygen absorption
and usually this leads to coloration around the heated zone - with the
color roughly corresponding to degree of oxygen reaction. but even 7
clean their welds so you can't tell if there's any disclororation. this
argument is incorrect.

<snip>

> Second, 6-4 sheet is designed to be used as a sheet, not as a tube.

incorrect.

> If
> it is formed into a tube, its grain structure can lead to premature
> tube failure.

absolutely incorrect.

> Indeed, a 6-4 tube will fail through fatigue cycling
> (repeated flexing) before it should, and independent fatigue tests
> show that tubing made from 6-4 sheet does not have the fatigue life of
> a properly drawn 3-2.5 tube.

incorrect. 6-4 still has perfectly acceptable fatigue properties.

> Consultation with titanium mills over the past decade tells us
> that seamless 6-4 is not on the near horizon.

really? someone had better tell reynolds!

[Only registered and activated users can see links. ]

10-10-2003, 05:39 PM

On Fri, 10 Oct 2003 13:08:26 +0000, Claire Petersky wrote:

> custom steel frame, I'd say why not? But there are still massive
> qualitative differences b/w Ti manufacturers' products,

According to whom? You have to take your source of information into
account, you know. Looks like your source is ... Seven.

> There are three primary differences between Seven and the other guys: 1.
> Seven uses butted tubing, and they have the longest experience working w/
> butten ti (a difficult thing to find in frames).

Lots of high-end ti bikes use butted tubing.

>*2. Seven uses a space
> industry grade 3Al-2.5V ti instead a sports or commercial grade, and also
> instead of 6AL-4V (a lower quality alloy for frames),

Their 3/2.5 is "better" than everyone else's?* Is that what they claim?
And 6/4 is not "lower quality"; it is, however, harder to work with. It
is also stiffer for the same size. Hard to find 6/4 in non-seamed tubing,
but it does exist if you are willing to pay for it.

> also on the side of value is the longevity of Ti. most people complain
> about the cost of Seven's, but in reality, they are not that bad compared
> with other truly high performance bicycles. plus, why would you want a
> couple of thousand dollars when you could have a great bicycle instead.

Note that that is a couple thousand _extra_....

> A small number of titanium frame builders incorporate Commercially Pure
> (CP) titanium into their frames.

These are mostly cheap knock-offs. Don't presume that Lightspeed will
try to sell you commercially-pure ti frames.

--

David L. Johnson

__o | You will say Christ saith this and the apostles say this; but
_`\(,_ | what canst thou say? -- George Fox.
(_)/ (_) |

10-10-2003, 08:31 PM

On 10 Oct 2003 13:08:26 -0700, [Only registered and activated users can see links. ] (Claire Petersky)
wrote:

>My co-worker has been hounding me to buy a Seven bike. Please critique
>this little essay he sent me:
>
>---
" the boss was inserted so far up the downtube that not
only did it look funny"

did he get a pay raise for getting him out?