Amazing ridership with disintegrating wheel

Track tandem blows a front tire, and in Flintstone fashion the front
carbon fiber disc wheel gets smaller and smaller until it looks like
they are brought down by a pedal strike. Amazing that the captain kept
it upright as long as he did.

http://www.youtube.com/watch?v=Ngv7Iu3y1o0

and another astonishing save, which has been posted befo

http://www.youtube.com/watch?v=Y-z0Kh0pvNM

--
"I wear the cheese, it does not wear me."

On 03/06/2010 05:50 PM, Tim McNamara wrote:
Track tandem blows a front tire, and in Flintstone fashion the front
carbon fiber disc wheel gets smaller and smaller until it looks like
they are brought down by a pedal strike. Amazing that the captain kept
it upright as long as he did.

http://www.youtube.com/watch?v=Ngv7Iu3y1o0

nice nerves o' steel. I'd have probably flinched.

nate


--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

On Mar 6, 2:50*pm, Tim McNamara wrote:
Track tandem blows a front tire, and in Flintstone fashion the front
carbon fiber disc wheel *gets smaller and smaller until it looks like
they are brought down by a pedal strike. *Amazing that the captain kept
it upright as long as he did.

http://www.youtube.com/watch?v=Ngv7Iu3y1o0

Tubular wheels are frequently credited as being more rideable than
clincher ones in the event of a puncture. Guess that doesn't apply to
light carbon fiber disc models.

On 3/6/2010 8:47 PM, * Still Just Me * wrote:
On Sat, 6 Mar 2010 17:31:12 -0800 (PST), Peter Rathmann
wrote:

Tubular wheels are frequently credited as being more rideable than
clincher ones in the event of a puncture. Guess that doesn't apply to
light carbon fiber disc models.

I wonder if it did the track flooring any favors also....


CF is unsuitable for structural components on a bicycle due to its
failure mode. Ride it with that knowledge.

PURE cf/composite is unsuitable.

With many (non-bicycle) CF items I've seen they used at least one layer
of kevlar in the middle somewhere. The kevlar is tough and holds things
together if the carbon get shattered.
~

In article
,
Peter Rathmann wrote:

On Mar 6, 2:50*pm, Tim McNamara wrote:
Track tandem blows a front tire, and in Flintstone fashion the
front carbon fiber disc wheel *gets smaller and smaller until it
looks like they are brought down by a pedal strike. *Amazing that
the captain kept it upright as long as he did.

http://www.youtube.com/watch?v=Ngv7Iu3y1o0

Tubular wheels are frequently credited as being more rideable than
clincher ones in the event of a puncture. Guess that doesn't apply
to light carbon fiber disc models.

I don't know why that myth exists. A flat tubular is more likely to
come off the rim than a flat clincher IME.

--
"I wear the cheese, it does not wear me."

In article ,
DougC wrote:

On 3/6/2010 8:47 PM, * Still Just Me * wrote:
On Sat, 6 Mar 2010 17:31:12 -0800 (PST), Peter Rathmann
wrote:

Tubular wheels are frequently credited as being more rideable than
clincher ones in the event of a puncture. Guess that doesn't apply to
light carbon fiber disc models.

I wonder if it did the track flooring any favors also....

There's something I hadn't thought about. I did think about shard of CF
out there waiting for the tires of other competitors.

--
"I wear the cheese, it does not wear me."

Tim McNamara wrote:

Track tandem blows a front tire, and in Flintstone fashion the front
carbon fiber disc wheel *gets smaller and smaller until it looks like
they are brought down by a pedal strike. *Amazing that the captain kept
it upright as long as he did.

http://www.youtube.com/watch?v=Ngv7Iu3y1o0

I wonder how their time on that run compares to another run using a
real tire on a real wheel.

Equipment that goes the distance has higher performance, in real
appreciable terms, than equipment that saves a tiny bit of weight or
aero drag but quickly fails. That principle works as well when the
relevant units are seconds as when they are decades.

Chalo

On Mar 9, 4:24*am, Chalo wrote:
Tim McNamara wrote:

Track tandem blows a front tire, and in Flintstone fashion the front
carbon fiber disc wheel *gets smaller and smaller until it looks like
they are brought down by a pedal strike. *Amazing that the captain kept
it upright as long as he did.

http://www.youtube.com/watch?v=Ngv7Iu3y1o0

I wonder how their time on that run compares to another run using a
real tire on a real wheel.

Equipment that goes the distance has higher performance, in real
appreciable terms, than equipment that saves a tiny bit of weight or
aero drag but quickly fails. *That principle works as well when the
relevant units are seconds as when they are decades.

Chalo

Dear Chalo,

Some improved spoked wheels may be as good or even better than disks
in zero side wind, but nothing else does as well as a disk with a side
wind, where the sail effect can actually produce a slight negative
drag.

A somewhat dated page with a table showing drag for several wheels:

http://www.analyticcycling.com/Wheel...20Aerodynamics

The conventional 36-spoke wheel has a drag coefficient of 0.0491,
about 35% higher than the 0.0361 and 0.0364 for the two disks tested.

If you plug in the 0.0491 and the 0.0361 wheel drags for both wheels
in the pursuit calculator on that site, the two-disk bike leads by
1.192 seconds and 17.2 meters after a standing start 4k run:

The results:
http://tinyurl.com/yghdwwk

The calculator:

http://www.analyticcycling.com/WheelsPursuit_Page.html

If you double the power from 550 watts to 1100 watts as a crude
estimate of a tandem, the 4k lead drops to 0.8 seconds and 15 meters.

Of course, rear disks are pretty much standard in high-level time
trials.

Cheers,

Carl Fogel

On Tue, 09 Mar 2010 18:51:46 -0500, * Still Just Me *
wrote:

On Tue, 9 Mar 2010 11:49:45 -0800 (PST), "
wrote:

Dear Chalo,

Some improved spoked wheels may be as good or even better than disks
in zero side wind, but nothing else does as well as a disk with a side
wind, where the sail effect can actually produce a slight negative
drag.

Isn't that video of an indoor track? The wind would be minimal
indoors, I'd wager :-)

Dear S,

Yes, but I thought that it was worth pointing out the striking sail
effect.

You did know about that, right? :-)

Cheers,

Carl Fogel

On 7 Mar, 17:11, Tim McNamara wrote:
In article ,

*DougC wrote:
On 3/6/2010 8:47 PM, * Still Just Me * wrote:
On Sat, 6 Mar 2010 17:31:12 -0800 (PST), Peter Rathmann
*wrote:

Tubular wheels are frequently credited as being more rideable than
clincher ones in the event of a puncture. *Guess that doesn't apply to
light carbon fiber disc models.

I wonder if it did the track flooring any favors also....

There's something I hadn't thought about. *I did think about shard of CF
out there waiting for the tires of other competitors.

--
"I wear the cheese, it does not wear me."

Ban them. That's a damn good reason.