New frame material

[J]

Roy Owen > wrote:
> It looks an awful lot loke a cheese grater, I hope it doesn't do that to
> you when you crash.

If you take a look at the high res (1200x1680) version of the frame
close-up, it seems that everything is pretty smooth. But it isn't
aerodynamic, and it looks like it would hold a ton of mud. I
suppose if this were ever used in a frame, it'd be covered with
some thin layer of mylar or something. But really, how much of
an improvement can there be? Hardtail MTB frames are already in
the 3lb range. Not much room for weight savings.

Justen

[Leonard Migliore]

Brigham Young University has just knocked all the cool frames out of the
water. Why go to titanium or carbon when you can have an IsoTruss?

http://byunews.byu.edu/archive05-Mar-isotrussbike.aspx

As I see it, the huge advantage the IsoTruss has over other methods of
frame construction is that anyone can see you have one from a great
distance. Also, it probably whistles at speed. I want mine now.

[Mike Beauchamp]

I've seen this posted before, at least links to the isotruss bike pictures.
I have to question the claim that it is more aerodynamic. Surely one single
pipe has to be more aerodynamic than that trusswork? It seems that something
like that would cause a lot of airflow disturbances no?

Granted, I don't know much about anything..

Mike

"Leonard Migliore" > wrote in message
...
> Brigham Young University has just knocked all the cool frames out of the
> water. Why go to titanium or carbon when you can have an IsoTruss?
>
> http://byunews.byu.edu/archive05-Mar-isotrussbike.aspx
>
> As I see it, the huge advantage the IsoTruss has over other methods of
> frame construction is that anyone can see you have one from a great
> distance. Also, it probably whistles at speed. I want mine now.

[Rich]

Mike Beauchamp wrote:
> I've seen this posted before, at least links to the isotruss bike pictures.
> I have to question the claim that it is more aerodynamic. Surely one single
> pipe has to be more aerodynamic than that trusswork? It seems that something
> like that would cause a lot of airflow disturbances no?

I agree. If aerodynamic was the goal they'd have stuck with one tube
and made the cross-section teardrop shaped. Although at MTB speeds it's
likely irrelevant.

Plus, cleaning this thing would be a pain.

Rich

[Roy Owen]

Leonard Migliore wrote:
> Brigham Young University has just knocked all the cool frames out of the
> water. Why go to titanium or carbon when you can have an IsoTruss?
>
> http://byunews.byu.edu/archive05-Mar-isotrussbike.aspx
>
> As I see it, the huge advantage the IsoTruss has over other methods of
> frame construction is that anyone can see you have one from a great
> distance. Also, it probably whistles at speed. I want mine now.
It looks an awful lot loke a cheese grater, I hope it doesn't do that to
you when you crash.

--
Roy Owen

Keep the leather side up,
and the rubber side down.

[RonSonic]

On Tue, 24 May 2005 20:42:31 -0700, Leonard Migliore > wrote:

>Brigham Young University has just knocked all the cool frames out of the
>water. Why go to titanium or carbon when you can have an IsoTruss?
>
>http://byunews.byu.edu/archive05-Mar-isotrussbike.aspx
>
>As I see it, the huge advantage the IsoTruss has over other methods of
>frame construction is that anyone can see you have one from a great
>distance. Also, it probably whistles at speed. I want mine now.

My admiration to the students and faculty. Anyone going to school in Utah who
finds a research subject that involves serious mountain biking is thinking with
all lobes engaged.

Ron

[Warren Block]

Rich > wrote:
> Mike Beauchamp wrote:
>> I've seen this posted before, at least links to the isotruss bike pictures.
>> I have to question the claim that it is more aerodynamic. Surely one single
>> pipe has to be more aerodynamic than that trusswork? It seems that something
>> like that would cause a lot of airflow disturbances no?
>
> I agree. If aerodynamic was the goal they'd have stuck with one tube
> and made the cross-section teardrop shaped. Although at MTB speeds it's
> likely irrelevant.
>
> Plus, cleaning this thing would be a pain.

In the high-res closeup, it appears that the down tube is covered in
clear plastic. That's probably to keep it from gathering dirt, but
consider that the resulting surface is bumpy. If that creates the
turbulence/boundary layer effect like the dimples on a golf ball, it
could be more aerodynamic than round tubes.

--
Warren Block * Rapid City, South Dakota * USA

[Mark Hickey]

RonSonic > wrote:

>My admiration to the students and faculty. Anyone going to school in Utah who
>finds a research subject that involves serious mountain biking is thinking with
>all lobes engaged.

I'd say they have a great future in marketing if nothing else ("less
breakable and more aerodynamic??? I doubt it). Still a very cool
project. I can't imagine what one would look like after a few months
in Arizona though (rocks would have to be really, really hard on all
those spindly little protrusions).

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $695 ti frame

[William McHale]

Mark Hickey > wrote:
> RonSonic > wrote:

>>My admiration to the students and faculty. Anyone going to school in Utah who
>>finds a research subject that involves serious mountain biking is thinking with
>>all lobes engaged.

> I'd say they have a great future in marketing if nothing else ("less
> breakable and more aerodynamic??? I doubt it). Still a very cool
> project. I can't imagine what one would look like after a few months
> in Arizona though (rocks would have to be really, really hard on all
> those spindly little protrusions).

Mark,
I wouldn't doubt that the frame is alot stronger than conventional frames.
Truss structures tend to be incredibly strong for their weight because most
forces that the structure can be subjected to can be redirected into
compression and tension. Heck, a basic bicycle frame is built on the same
idea; the only difference being that its two triangles limit the redirection
of forces mostly into the vertical realm.

The aerodynamics is difficult to assess just from the appearance of the frame;
as someone pointed out a golf ball is alot more aerodynamic than a perfect
sphere would be.

--
Bill

[Mark Hickey]

William McHale > wrote:

>Mark Hickey > wrote:
>> RonSonic > wrote:
>
>> I'd say they have a great future in marketing if nothing else ("less
>> breakable and more aerodynamic??? I doubt it). Still a very cool
>> project. I can't imagine what one would look like after a few months
>> in Arizona though (rocks would have to be really, really hard on all
>> those spindly little protrusions).
>
>Mark,
>I wouldn't doubt that the frame is alot stronger than conventional frames.
>Truss structures tend to be incredibly strong for their weight because most
>forces that the structure can be subjected to can be redirected into
>compression and tension. Heck, a basic bicycle frame is built on the same
>idea; the only difference being that its two triangles limit the redirection
>of forces mostly into the vertical realm.

They're not really changing that much in the way of stress on the
frame. It might help to think of a regular tube as a structure with
an infinite number of interconnected trusses (and that would actually
be pretty much correct at a molecular level I suppose).

>The aerodynamics is difficult to assess just from the appearance of the frame;
>as someone pointed out a golf ball is alot more aerodynamic than a perfect
>sphere would be.

That's only because of the cavitation that's created by the wicked
spin that's put on the ball. I don't believe there'd be much
difference in the terminal velocity of a golf ball-size and weight
identical smooth ball dropped from an airplane.

I'm trying to picture the air flow over/through those funky tubes -
only one word comes to mind... turbulence. Lots o' turbulence. I
know aerodynamics is sometimes voodoo science, but I find it hard to
believe I could make a tube and fabric airplane go faster by taking
the fabric off...

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $695 ti frame

[Michael Warner]

On Wed, 25 May 2005 00:41:05 -0400, Mike Beauchamp wrote:

> I've seen this posted before, at least links to the isotruss bike pictures.
> I have to question the claim that it is more aerodynamic. Surely one single
> pipe has to be more aerodynamic than that trusswork? It seems that something
> like that would cause a lot of airflow disturbances no?

Presumably you'd cover it with a film of some sort (clear, obviously, so
everyone could see your unusual and expensive frame).

--
bpo gallery at http://www4.tpgi.com.au/users/mvw1/bpo