TdF tech

Qui si parla Campagnolo said:

This aspect of this race is interesting to most of us on the NG, of
course. AND I can even ignore the dude advertising Bontrager carbon
tubular wheels..."everyday wheels!!", I wonder if all the clones rushed
down to their local Trek dealer to get some...like Assos chamois cream
when Lance mentioned it...

BUT-pulleys falling out of rear derailleurs(Oooops) and the [censored] poor
braking of carbon rims...really spectacular crash on Sundays stage.

I used to carbon wheels for a while and with yellow Swissstop pads the
braking was great, except in the rain, when it was non-existant until
the pad squeegied the rim dry, then Ooops! big braking. Not good in the
rain...

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

Quoted message said:

Guy that works for me...small, compact, light, teeny discs? for carbon
rim-ed race wheels?

When you look at how flimsy caliper brakes really are, and they do a
fine job, it really seems that a really tiny dics could do the job just
as well. If the rim didn't have to deal with braking, it could be
different aero/lighter/whatever too. Sign me up!

Quoted message said:

Not actually a bad idea. Like Moto-GP...the stuff they race doesn't
have to be available to the public...

But why not? The public is a good test bed!

Joseph

Quoted message said:

Qui si parla Campagnolo said:

This aspect of this race is interesting to most of us on the NG, of
course. AND I can even ignore the dude advertising Bontrager carbon
tubular wheels..."everyday wheels!!", I wonder if all the clones rushed
down to their local Trek dealer to get some...like Assos chamois cream
when Lance mentioned it...

BUT-pulleys falling out of rear derailleurs(Oooops) and the [censored] poor
braking of carbon rims...really spectacular crash on Sundays stage.

I used to carbon wheels for a while and with yellow Swissstop pads the
braking was great, except in the rain, when it was non-existant until
the pad squeegied the rim dry, then Ooops! big braking. Not good in the
rain...

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

Quoted message said:

Guy that works for me...small, compact, light, teeny discs? for carbon
rim-ed race wheels?

When you look at how flimsy caliper brakes really are, and they do a
fine job, it really seems that a really tiny dics could do the job just
as well. If the rim didn't have to deal with braking, it could be
different aero/lighter/whatever too. Sign me up!

Quoted message said:

Not actually a bad idea. Like Moto-GP...the stuff they race doesn't
have to be available to the public...

But why not? The public is a good test bed!

More than a "good test bed", selling high level racing stuff to the
general public is enormously profitable, as it always has been. Now, in
the day when the TdF could be won on a steel frame with Campy NR parts
and sensible wheels, buying the "bike that Eddy M. rode" (for example)
wasn't such a crazy idea. But today, things are very different in terms
of the life expectancy of some of these "edge-of-the-art" frames,
forks, parts and wheels. Only when recreational riders get fed up with
frames, wheels, etc., that last only a year or two will things change
in the marketplace,

Quoted message said:

Qui si parla Campagnolo said:

This aspect of this race is interesting to most of us on the NG, of
course. AND I can even ignore the dude advertising Bontrager carbon
tubular wheels..."everyday wheels!!", I wonder if all the clones rushed
down to their local Trek dealer to get some...like Assos chamois cream
when Lance mentioned it...

BUT-pulleys falling out of rear derailleurs(Oooops) and the [censored] poor
braking of carbon rims...really spectacular crash on Sundays stage.

I used to carbon wheels for a while and with yellow Swissstop pads the
braking was great, except in the rain, when it was non-existant until
the pad squeegied the rim dry, then Ooops! big braking. Not good in the
rain...

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

I think he just hung on longer and came closer to saving it. That's where my
worst crashes come from. It's like poker, every save raises the bet and in the
end you either save it big time or eat it all the worse.

Quoted message said:

Quoted message said:

Guy that works for me...small, compact, light, teeny discs? for carbon
rim-ed race wheels?

When you look at how flimsy caliper brakes really are, and they do a
fine job, it really seems that a really tiny dics could do the job just
as well. If the rim didn't have to deal with braking, it could be
different aero/lighter/whatever too. Sign me up!

How much more stress does hub braking impose on the spokes than rim braking.
There's a rotational component that doesn't exist in rim braking, is that
significant beyond barring radial spoke schemes? What additional forces are
applied to the fork, there's both torsion and flex that doesn't happen with
caliper brakes. The flex alone can be a problem if cx experience with canti's
applies.

Quoted message said:

Quoted message said:

Not actually a bad idea. Like Moto-GP...the stuff they race doesn't
have to be available to the public...

But why not? The public is a good test bed!

Because a lot of things that make sense when you've got team mechanics are just
plain silly for normal riders.

Ron

RonSonic said:

Quoted message said:

Qui si parla Campagnolo said:

This aspect of this race is interesting to most of us on the NG, of
course. AND I can even ignore the dude advertising Bontrager carbon
tubular wheels..."everyday wheels!!", I wonder if all the clones rushed
down to their local Trek dealer to get some...like Assos chamois cream
when Lance mentioned it...

BUT-pulleys falling out of rear derailleurs(Oooops) and the [censored] poor
braking of carbon rims...really spectacular crash on Sundays stage.

I used to carbon wheels for a while and with yellow Swissstop pads the
braking was great, except in the rain, when it was non-existant until
the pad squeegied the rim dry, then Ooops! big braking. Not good in the
rain...

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

I think he just hung on longer and came closer to saving it. That's where my
worst crashes come from. It's like poker, every save raises the bet and in the
end you either save it big time or eat it all the worse.

There you go!

Quoted message said:

Quoted message said:

Quoted message said:

Guy that works for me...small, compact, light, teeny discs? for carbon
rim-ed race wheels?

When you look at how flimsy caliper brakes really are, and they do a
fine job, it really seems that a really tiny dics could do the job just
as well. If the rim didn't have to deal with braking, it could be
different aero/lighter/whatever too. Sign me up!

How much more stress does hub braking impose on the spokes than rim braking.
There's a rotational component that doesn't exist in rim braking, is that
significant beyond barring radial spoke schemes? What additional forces are
applied to the fork, there's both torsion and flex that doesn't happen with
caliper brakes. The flex alone can be a problem if cx experience with canti's
applies.

Watching a huge sprinter stomp a 200m sprint from a stop shows spoked
wheels tolerate quite a bit. Not to mention all the MTB bikes out there
with discs. Rotational flex on the fork might be a bit more, but again
I refer to the flimsy caliper construction. Look at that puny bolt that
holds the whole thing together and gets stress at all sorts of
non-optimal angles and seems to hold up just fine. I'll bet rotational
stress on the fork isn't such a big deal.

Quoted message said:

Quoted message said:

Quoted message said:

Not actually a bad idea. Like Moto-GP...the stuff they race doesn't
have to be available to the public...

But why not? The public is a good test bed!

Because a lot of things that make sense when you've got team mechanics are just
plain silly for normal riders.

I didn't mean to imply that using or buying such things was a good
idea. Selling such stuff however is a different story!

Joseph

Qui si parla Campagnolo said:

Guy that works for me...small, compact, light, teeny discs?

Hey, as long as his wife's happy...

Bill "someone hi-jacked my account to post that" S.

Quoted message said:

Qui si parla Campagnolo said:

BUT-pulleys falling out of rear derailleurs(Oooops) and the [censored] poor
braking of carbon rims...really spectacular crash on Sundays stage.

I used to carbon wheels for a while and with yellow Swissstop pads the
braking was great, except in the rain, when it was non-existant until
the pad squeegied the rim dry, then Ooops! big braking. Not good in the
rain...

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

Verbrugghe was leading (IIRC, unless he was second wheel) and he
went around the corner too fast, he swung wide and went into the
guardrail and over. The next three guys saved it - maybe they had
enough reaction time to brake a little, or just didn't panic as much -
but Canada in fifth wheel got wobbly, swung wide and took Kessler
into the guardrail with him.

I don't think it actually had to do with poor braking. Maybe bad
traction if there was gravel or tar on the road, but it was dry, so
wet braking shouldn't be an issue. The problem is, it was a 90
degree bend with no favorable camber - if you hit the apex too
fast, it's too late for braking to help much.

Quoted message said:

RonSonic said:

Quoted message said:

Qui si parla Campagnolo wrote:
> This aspect of this race is interesting to most of us on the NG, of
> course. AND I can even ignore the dude advertising Bontrager carbon
> tubular wheels..."everyday wheels!!", I wonder if all the clones rushed
> down to their local Trek dealer to get some...like Assos chamois cream
> when Lance mentioned it...
>
> BUT-pulleys falling out of rear derailleurs(Oooops) and the [censored] poor
> braking of carbon rims...really spectacular crash on Sundays stage.

I used to carbon wheels for a while and with yellow Swissstop pads the
braking was great, except in the rain, when it was non-existant until
the pad squeegied the rim dry, then Ooops! big braking. Not good in the
rain...

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

I think he just hung on longer and came closer to saving it. That's where my
worst crashes come from. It's like poker, every save raises the bet and in the
end you either save it big time or eat it all the worse.

There you go!

Quoted message said:

Quoted message said:

> Guy that works for me...small, compact, light, teeny discs? for carbon
> rim-ed race wheels?

When you look at how flimsy caliper brakes really are, and they do a
fine job, it really seems that a really tiny dics could do the job just
as well. If the rim didn't have to deal with braking, it could be
different aero/lighter/whatever too. Sign me up!

How much more stress does hub braking impose on the spokes than rim braking.
There's a rotational component that doesn't exist in rim braking, is that
significant beyond barring radial spoke schemes? What additional forces are
applied to the fork, there's both torsion and flex that doesn't happen with
caliper brakes. The flex alone can be a problem if cx experience with canti's
applies.

Watching a huge sprinter stomp a 200m sprint from a stop shows spoked
wheels tolerate quite a bit. Not to mention all the MTB bikes out there
with discs. Rotational flex on the fork might be a bit more, but again
I refer to the flimsy caliper construction. Look at that puny bolt that
holds the whole thing together and gets stress at all sorts of
non-optimal angles and seems to hold up just fine. I'll bet rotational
stress on the fork isn't such a big deal.

Quoted message said:

Quoted message said:

>
> Not actually a bad idea. Like Moto-GP...the stuff they race doesn't
> have to be available to the public...

But why not? The public is a good test bed!

Because a lot of things that make sense when you've got team mechanics are just
plain silly for normal riders.

I didn't mean to imply that using or buying such things was a good
idea. Selling such stuff however is a different story!

And it is the selling of such stuff that makes its existence possible. Back when
only the pro peloton got the good stuff it wasn't worthwhile to do more than
give it the drillium treatment. Now, with enough guys out there wanting the
latest and greatest it makes sense to invest in bleeding edge bike technology.

Ron

Quoted message said:

I don't think it actually had to do with poor braking. Maybe bad
traction if there was gravel or tar on the road, but it was dry, so
wet braking shouldn't be an issue. The problem is, it was a 90
degree bend with no favorable camber - if you hit the apex too
fast, it's too late for braking to help much.

Wasn't that brown patch of stuff extending from the gutter out ~3ft.
into the road, sand? I've assumed that the tour organization sweeps the
course prior to the race. Or is it like hockey where the NHL wants
blood & guts?

Regards, John

john said:

Quoted message said:

I don't think it actually had to do with poor braking. Maybe bad
traction if there was gravel or tar on the road, but it was dry, so
wet braking shouldn't be an issue. The problem is, it was a 90
degree bend with no favorable camber - if you hit the apex too
fast, it's too late for braking to help much.

Wasn't that brown patch of stuff extending from the gutter out ~3ft.
into the road, sand? I've assumed that the tour organization sweeps the
course prior to the race.

Yeah right, 230 km of road to sweep and that's just one stage...

Lou
--
Posted by news://news.nb.nu

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In article <[email hidden]>,

Qui si parla Campagnolo said:

Not actually a bad idea. Like Moto-GP...the stuff they race doesn't
have to be available to the public...

_ Actually, I think the UCI rules do require that they race on
stuff that's available to the public. For some arcane definition
of "public" and "available" that I don't quite understand.

_ Booker C. Bense

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Quoted message said:

Quoted message said:

Qui si parla Campagnolo said:

BUT-pulleys falling out of rear derailleurs(Oooops) and the [censored] poor
braking of carbon rims...really spectacular crash on Sundays stage.

I used to carbon wheels for a while and with yellow Swissstop pads the
braking was great, except in the rain, when it was non-existant until
the pad squeegied the rim dry, then Ooops! big braking. Not good in the
rain...

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

Verbrugghe was leading (IIRC, unless he was second wheel) and he
went around the corner too fast, he swung wide and went into the
guardrail and over. The next three guys saved it - maybe they had
enough reaction time to brake a little, or just didn't panic as much -
but Canada in fifth wheel got wobbly, swung wide and took Kessler
into the guardrail with him.

I didn't see what happened to Verbrugghe.

Kessler was working his way to the back of the paceline and was on the
left of Canada, a bit behind him as they went through a right turn.
Canadas front wheel washed out on the sand, and he dumped it onto his
shoulder and slid on his back into the rail on the opposite side of the
road. Kessler locked up the back wheel trying to avoid him, as he was
sliding in front of Kessler. I don't think Kessler actually hit him, he
just shadowed him into the rail.

Quoted message said:

I don't think it actually had to do with poor braking. Maybe bad
traction if there was gravel or tar on the road, but it was dry, so
wet braking shouldn't be an issue. The problem is, it was a 90
degree bend with no favorable camber - if you hit the apex too
fast, it's too late for braking to help much.

It wasn't a particularly sharp corner. I don't think any braking was
involved except for Kessler locking the back wheel, which didn't cause
him to fall, he was in control (sort of) right up until he hit the
rail.

Joseph

Quoted message said:

Quoted message said:

Quoted message said:

Qui si parla Campagnolo wrote:

> BUT-pulleys falling out of rear derailleurs(Oooops) and the [censored] poor
> braking of carbon rims...really spectacular crash on Sundays stage.

I used to carbon wheels for a while and with yellow Swissstop pads the
braking was great, except in the rain, when it was non-existant until
the pad squeegied the rim dry, then Ooops! big braking. Not good in the
rain...

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

Verbrugghe was leading (IIRC, unless he was second wheel) and he
went around the corner too fast, he swung wide and went into the
guardrail and over. The next three guys saved it - maybe they had
enough reaction time to brake a little, or just didn't panic as much -
but Canada in fifth wheel got wobbly, swung wide and took Kessler
into the guardrail with him.

I didn't see what happened to Verbrugghe.

Kessler was working his way to the back of the paceline and was on the
left of Canada, a bit behind him as they went through a right turn.
Canadas front wheel washed out on the sand, and he dumped it onto his
shoulder and slid on his back into the rail on the opposite side of the
road. Kessler locked up the back wheel trying to avoid him, as he was
sliding in front of Kessler. I don't think Kessler actually hit him, he
just shadowed him into the rail.

Quoted message said:

I don't think it actually had to do with poor braking. Maybe bad
traction if there was gravel or tar on the road, but it was dry, so
wet braking shouldn't be an issue. The problem is, it was a 90
degree bend with no favorable camber - if you hit the apex too
fast, it's too late for braking to help much.

It wasn't a particularly sharp corner. I don't think any braking was
involved except for Kessler locking the back wheel, which didn't cause
him to fall, he was in control (sort of) right up until he hit the
rail.

Joseph

Lou Holtman said:

john said:

Wasn't that brown patch of stuff extending from the gutter out ~3ft.
into the road, sand? I've assumed that the tour organization sweeps the
course prior to the race.

Yeah right, 230 km of road to sweep and that's just one stage...

Quoted message said:

Lou

Why not? You mean to say that every town & county (or French
equivalent) doesn't have a sweeper or 2 that could sweep, say, 15km of
road each in the morning of the stage? Or if necessary starting @
midnight. This ain't the Tour de Podunk. My understanding is towns beg
&/ or pay for the privilege of having the tour pass through their
neighborhood. I don't like to see my favorites loose time due to flats.
Nor do I like seeing careers cut short by crashes. Nor, for that mater,
do I like to see blood & guts.

Regards, John

john said:

Quoted message said:

I don't think it actually had to do with poor braking. Maybe bad
traction if there was gravel or tar on the road, but it was dry, so
wet braking shouldn't be an issue. The problem is, it was a 90
degree bend with no favorable camber - if you hit the apex too
fast, it's too late for braking to help much.

Wasn't that brown patch of stuff extending from the gutter out ~3ft.
into the road, sand? I've assumed that the tour organization sweeps the
course prior to the race. Or is it like hockey where the NHL wants
blood & guts?

Yes they sweep (so I'm told, I have not actually been to
the Tour). In the video, it looks like the loose stuff is mostly
to the right of the fog line. Verbrugghe, the first rider, goes
through the apex and keeps the bike upright all the way
into the barrier, so it's not the type of crash where one hits
the loose stuff and immediately low-sides. I think he
probably did take a worse line than riders 2,3,4. You
can see rider 3 do a wiggle, which could be a brief grab
of the brake, an instinctual twitch as Verbrugghe goes
wrong, or both. But he keeps it upright. Rider 5, Canada,
hits the loose stuff and loses traction directly, unlike
rider 1 - he may have been grabbing the rear brake.

john said:

Quoted message said:

I don't think it actually had to do with poor braking. Maybe bad
traction if there was gravel or tar on the road, but it was dry, so
wet braking shouldn't be an issue. The problem is, it was a 90
degree bend with no favorable camber - if you hit the apex too
fast, it's too late for braking to help much.

Wasn't that brown patch of stuff extending from the gutter out ~3ft.
into the road, sand? I've assumed that the tour organization sweeps the
course prior to the race.

Big assumption. I'm not sure it's true.

JT

****************************
Remove "remove" to reply
Visit http://www.jt10000.com
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[email hidden] wrote:

-snip-

Quoted message said:

It was obvious why the Sunier Duval guy and Kessler bit it, but what
happened to the other guy?

-snip-

Verbrugghe (the one flying into and over the barrier to the right of
Kessler / Cañada, that the video photographer missed) was operated on
Sunday evening, for a broken femur sustained in the crash. Complex
fracture. See cyclingnews.com and similar sources for details.

/Robert

My read of viewing the tape is Verbrugge did not hit his brakes and did
not intend to, but may have had to not take the closest apex because of
the loose stuff, kept his speed and was in the wrong line and went over the
rail. Look, those guys are going fast and a few inches makes a tremendous
difference. Should that area have been swept? Yes! Is it possible for every
inch of the road to be meticulously maintained? No! An unfortunate event
in a risky sport.

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

Quoted message said:

john said:

Quoted message said:

I don't think it actually had to do with poor braking. Maybe bad
traction if there was gravel or tar on the road, but it was dry, so
wet braking shouldn't be an issue. The problem is, it was a 90
degree bend with no favorable camber - if you hit the apex too
fast, it's too late for braking to help much.

Wasn't that brown patch of stuff extending from the gutter out ~3ft.
into the road, sand? I've assumed that the tour organization sweeps the
course prior to the race. Or is it like hockey where the NHL wants
blood & guts?

Yes they sweep (so I'm told, I have not actually been to
the Tour). In the video, it looks like the loose stuff is mostly
to the right of the fog line. Verbrugghe, the first rider, goes
through the apex and keeps the bike upright all the way
into the barrier, so it's not the type of crash where one hits
the loose stuff and immediately low-sides. I think he
probably did take a worse line than riders 2,3,4. You
can see rider 3 do a wiggle, which could be a brief grab
of the brake, an instinctual twitch as Verbrugghe goes
wrong, or both. But he keeps it upright. Rider 5, Canada,
hits the loose stuff and loses traction directly, unlike
rider 1 - he may have been grabbing the rear brake.

RS said:

My read of viewing the tape is Verbrugge did not hit his brakes and did
not intend to, but may have had to not take the closest apex because of
the loose stuff, kept his speed and was in the wrong line and went over the
rail. Look, those guys are going fast and a few inches makes a tremendous
difference. Should that area have been swept? Yes! Is it possible for every
inch of the road to be meticulously maintained? No! An unfortunate event
in a risky sport.

The OLN crew mentioned that race cotrol had announced to all team
managers that the road going down was dangerous in places due to the
heat, something to do with the tar being less solid, IIRC.

Quoted message said:

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

Quoted message said:

john said:

[email hidden] wrote:

>
> I don't think it actually had to do with poor braking. Maybe bad
> traction if there was gravel or tar on the road, but it was dry, so
> wet braking shouldn't be an issue. The problem is, it was a 90
> degree bend with no favorable camber - if you hit the apex too
> fast, it's too late for braking to help much.

Wasn't that brown patch of stuff extending from the gutter out ~3ft.
into the road, sand? I've assumed that the tour organization sweeps the
course prior to the race. Or is it like hockey where the NHL wants
blood & guts?

Yes they sweep (so I'm told, I have not actually been to
the Tour). In the video, it looks like the loose stuff is mostly
to the right of the fog line. Verbrugghe, the first rider, goes
through the apex and keeps the bike upright all the way
into the barrier, so it's not the type of crash where one hits
the loose stuff and immediately low-sides. I think he
probably did take a worse line than riders 2,3,4. You
can see rider 3 do a wiggle, which could be a brief grab
of the brake, an instinctual twitch as Verbrugghe goes
wrong, or both. But he keeps it upright. Rider 5, Canada,
hits the loose stuff and loses traction directly, unlike
rider 1 - he may have been grabbing the rear brake.

Yes, Cyclingnews also reported undulating road conditions from heat. I'm
sure Verbruge tried to get out as he saw the rail approaching, probably
braked. Very tough sport, very tough conditions. I love to watch races but this
does happen.

In article <[email hidden]>,
rb20170REMOVE.yahoo.com@ says...

Quoted message said:

RS said:

My read of viewing the tape is Verbrugge did not hit his brakes and did
not intend to, but may have had to not take the closest apex because of
the loose stuff, kept his speed and was in the wrong line and went over the
rail. Look, those guys are going fast and a few inches makes a tremendous
difference. Should that area have been swept? Yes! Is it possible for every
inch of the road to be meticulously maintained? No! An unfortunate event
in a risky sport.

The OLN crew mentioned that race cotrol had announced to all team
managers that the road going down was dangerous in places due to the
heat, something to do with the tar being less solid, IIRC.

Quoted message said:

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

Quoted message said:

john wrote:
> [email hidden] wrote:
>
> >
> > I don't think it actually had to do with poor braking. Maybe bad
> > traction if there was gravel or tar on the road, but it was dry, so
> > wet braking shouldn't be an issue. The problem is, it was a 90
> > degree bend with no favorable camber - if you hit the apex too
> > fast, it's too late for braking to help much.
>
> Wasn't that brown patch of stuff extending from the gutter out ~3ft.
> into the road, sand? I've assumed that the tour organization sweeps the
> course prior to the race. Or is it like hockey where the NHL wants
> blood & guts?

Yes they sweep (so I'm told, I have not actually been to
the Tour). In the video, it looks like the loose stuff is mostly
to the right of the fog line. Verbrugghe, the first rider, goes
through the apex and keeps the bike upright all the way
into the barrier, so it's not the type of crash where one hits
the loose stuff and immediately low-sides. I think he
probably did take a worse line than riders 2,3,4. You
can see rider 3 do a wiggle, which could be a brief grab
of the brake, an instinctual twitch as Verbrugghe goes
wrong, or both. But he keeps it upright. Rider 5, Canada,
hits the loose stuff and loses traction directly, unlike
rider 1 - he may have been grabbing the rear brake.