Sharp Cornering Bike?

wrote:

Frame geometry can affect handling.

Trials bikes are designed for quick handling at low-speed,
so they don't do well at high speed down a ski-run in
summer.

Similarly, Hans Rey doesn't use a longer wheelbase touring
bicycle to leap on and off picnic tables and cavort among
boulders.

There's not a lot of difference in the geometry seen in
bicycles used for the same kind of racing.

In any case, cornering is rarely emphasized in paved bicycle
races because the engine tends to be far more important.

There just isn't the fiddling with front-end geometry,
suspension, and tire compounds that you see in motorcycle
racing.

Bicyclists don't like to change their front ends, suspension
is absent from road bicycles, big snip

Carl, I am compelled to pick a nit here. Road bikes most certainly do
have suspension: the air contained in the flexible tires. A short ride
on a bike with solid tires will be convincing.

In addition to that, the rider's legs provide an excellent suspension as
they can magically turn most of the rider's weight into suspended
weight. You may argue that the rider's legs can hardly be considered
part of the bike. You would be correct, but what's the use of a bike
without a rider?

--
Ted Bennett

C Wright wrote:
The latest issue of Bicycling Magazine (Sept. 2005) has a review of a
Pinarello F4:13 and, among many other things, they comment that "it's also
one of the sharpest-cornering bikes we've ever ridden - your could
practically rub your hip on the road and not worry about blowing a turn."
That got me to wondering if, by design, one bike can really corner better
than another and, if so, why?

easiest thing is go to your lbs and actually /try/ different machines.
you'll form your own opinion real quick on whether one bike can corner
better than the next.

If cheap entry level bikes are excluded and
the comparison is limited to bikes with high quality aluminum, carbon or Ti
frames and a reasonably good set of wheels why would one bike be able to
corner better than another?

geometry, frame flex [affecting both wheel alignment through torsion and
reaction to your weight], lateral flex of wheels, tires - /all/ can
affect cornering on a bike. if those factors are analyzed & understood,
there's no reason why you can't design one bike to corner better than
the next.

Or, would the major factor simply be tire
compound?
Chuck

On Sat, 06 Aug 2005 20:12:09 GMT, Ted Bennett
wrote:

wrote:

Frame geometry can affect handling.

Trials bikes are designed for quick handling at low-speed,
so they don't do well at high speed down a ski-run in
summer.

Similarly, Hans Rey doesn't use a longer wheelbase touring
bicycle to leap on and off picnic tables and cavort among
boulders.

There's not a lot of difference in the geometry seen in
bicycles used for the same kind of racing.

In any case, cornering is rarely emphasized in paved bicycle
races because the engine tends to be far more important.

There just isn't the fiddling with front-end geometry,
suspension, and tire compounds that you see in motorcycle
racing.

Bicyclists don't like to change their front ends, suspension
is absent from road bicycles, big snip

Carl, I am compelled to pick a nit here. Road bikes most certainly do
have suspension: the air contained in the flexible tires. A short ride
on a bike with solid tires will be convincing.

In addition to that, the rider's legs provide an excellent suspension as
they can magically turn most of the rider's weight into suspended
weight. You may argue that the rider's legs can hardly be considered
part of the bike. You would be correct, but what's the use of a bike
without a rider?

Dear Ted,

Er, in your haste to pick your nit, you snipped this:

"And tire inflation is about as close as pavement bicycles
get to suspension."

But I've gotten excited myself before I finished posts, so I
really shouldn't complain.

And I do like your point about the rider's legs acting as
suspension, although a lot of cornering pictures show the
rider pretty much with his outside leg down and stiff--much
of the time, the magic is more potential than actual.

However, the original poster was asking what difference a
particular bike would make in cornering, so he's probably
going to rule your leg-suspension point out, even though I
like it.

Cheers,

Carl Fogel

C Wright wrote:
The latest issue of Bicycling Magazine (Sept. 2005) has a review of a
Pinarello F4:13 and, among many other things, they comment that "it's also
one of the sharpest-cornering bikes we've ever ridden - your could
practically rub your hip on the road and not worry about blowing a turn."
That got me to wondering if, by design, one bike can really corner better
than another and, if so, why? If cheap entry level bikes are excluded and
the comparison is limited to bikes with high quality aluminum, carbon or Ti
frames and a reasonably good set of wheels why would one bike be able to
corner better than another? Or, would the major factor simply be tire
compound?
Chuck


Pretty much it (tire compound). The excerpt doesn't go into details, but
the impression is that they're talking about lean angle and slipout.
From a practical (what an idea!) perspective, as Jobst often points
out, nobody corners to the limit deliberately, which, in the absence of
reasonably sophisticated (hint: not found at Buycycling magazines
facilities) equipment, is the only way to determine slipout angle. In
other words, they are talking out of their asses, something they're all
too well known to do. That bike and tire combo might be out-cornered by
a Schwinn Paperboy and they'd never know.

Dear Ted,

Er, in your haste to pick your nit, you snipped this:

"And tire inflation is about as close as pavement bicycles
get to suspension."

Drat! Itchy trigger finger.


But I've gotten excited myself before I finished posts, so I
really shouldn't complain.

And I do like your point about the rider's legs acting as
suspension, although a lot of cornering pictures show the
rider pretty much with his outside leg down and stiff--much
of the time, the magic is more potential than actual.

However, the original poster was asking what difference a
particular bike would make in cornering, so he's probably
going to rule your leg-suspension point out, even though I
like it.

Cheers,

Carl Fogel

Nicely put. I would encourage those afflicted with the stiff-leg
syndrome to try to relax more on the bike by putting the pedals fore and
aft. Works in corners well, at least for the ones you coast through.

I agree with "Jim Beam" that various bikes will handle differently, for
many interesting reasons. Whether those differences make any real
difference in the fastest time through the turn (one testable aspect of
handling), is open to question.

Ted

--
Ted Bennett

Chuck Wright writes:

The latest issue of Bicycling Magazine (Sept. 2005) has a review of
a Pinarello F4:13 and, among many other things, they comment that
"it's also one of the sharpest-cornering bikes we've ever ridden -
your could practically rub your hip on the road and not worry about
blowing a turn."

Well, with that kind of hyperbole, I can't take anything these guys
wrote seriously. They visualize themselves as Motorcycle GP racers
cornering with their Teflon knee buttons sliding on the road.

That got me to wondering if, by design, one bike can really corner
better than another and, if so, why? If cheap entry level bikes are
excluded and the comparison is limited to bikes with high quality
aluminum, carbon or Titanium frames and a reasonably good set of
wheels why would one bike be able to corner better than another?
Or, would the major factor simply be tire compound?

As the title claims, they are attributing this to the bicycle. The
only cornering of interest occurs when riding fast, not parking lot
gymnastics, so it cannot be the geometry of the bicycle because
significant changes in rake and trail are unacceptable to bicyclists
who do this sort of thing (in criteriums).

The testers apparently succumbed to marketing suggestions and possibly
some unnamed feature of the bicycle that made these inexperienced
testers believe what they were told. For instance, while working in
the auto business, I saw testers fooled by a "power kit" that one of
two otherwise identical cars was said to have. They found it improved
acceleration out of turns and was generally better. The power kit
consisted of a lighter gas pedal return spring.

Jobst Brandt

C Wright wrote:

The latest issue of Bicycling Magazine (Sept. 2005) has a review of a
Pinarello F4:13 and, among many other things, they comment that "it's also
one of the sharpest-cornering bikes we've ever ridden - your could
practically rub your hip on the road and not worry about blowing a turn."
That got me to wondering if, by design, one bike can really corner better
than another and, if so, why? If cheap entry level bikes are excluded and
the comparison is limited to bikes with high quality aluminum, carbon or Ti
frames and a reasonably good set of wheels why would one bike be able to
corner better than another? Or, would the major factor simply be tire
compound?

If there really WAS a bike that allowed taking a corner significantly
faster than any other bike on the market (or at least much faster than
most), it would be virtually impossible to lose a criterium race from
the lead group since you could simply motor through the final corner
5mph faster than everyone else and drop them like rocks down the
finish straight.

.... which of course makes the whole thing sound ridiculous (like the
equally bogus claims of several minutes certain aero equipment can
save in a time trial, since all it would take for anyone in the top
half of the Tour de France time trial to blow Lance away would have
been that magical equipment).

My guess is that the marketing folks from the company involved put an
idea in the magazine writer's head prior to the test ride, so the
writer felt whatever it was he expected...

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame

"Peter Cole" wrote: (clip) Schwinn Paperboy (clip)
^^^^^^^^^^^^^
I drive a Subaru "Outback." and ride a Dahon "Boardwalk," but I am not
familiar with that particular model of Schwinn.

I think part of the discussion on the differences in bicycles' ability to
corner has wandered across into different territory, about differences in
maneuverability. I know, on theoretical grounds, and also from experience,
that differences in fork angle, trail, wheelbase, etc, can have a marked
effect on the way a bike handles. Bikes that are designed for riding fast
on the road are designed differently from enduro or trials bikes. It's like
comparing a limo to a Jeep. It could be said that a Jeep turns faster (is
more nimble) but doesn't corner faster (spins out easier or rolls.) on high
speed turns

I think there are two topics here, and we're not all talking about the same
thing.

"Leo Lichtman" wrote in message
...

"Peter Cole" wrote: (clip) Schwinn Paperboy (clip)
^^^^^^^^^^^^^
I drive a Subaru "Outback." and ride a Dahon "Boardwalk," but I am not
familiar with that particular model of Schwinn.

I think part of the discussion on the differences in bicycles' ability to
corner has wandered across into different territory, about differences in
maneuverability. I know, on theoretical grounds, and also from
experience, that differences in fork angle, trail, wheelbase, etc, can
have a marked effect on the way a bike handles. Bikes that are designed
for riding fast on the road are designed differently from enduro or trials
bikes. It's like comparing a limo to a Jeep. It could be said that a
Jeep turns faster (is more nimble) but doesn't corner faster (spins out
easier or rolls.) on high speed turns

I think there are two topics here, and we're not all talking about the
same thing.


With you Leo.

The fork on my last bike had really deep, forward facing drop-outs with
bolts to adjust how far forward or back the front axle was. Somewhere around
an inch of adjustment possible.

I remember experimenting with this from time to time and noted a marked
difference in handling depending on how this was set.

Full forward, the bike tracked very straight but took more effort to turn
the wheel at speed.
Full back and the bike felt comparitively twitchy but was easier to maneuver
in tight spaces.

When I read the original post on this topic, that was the type of handling
description I thought was implied by the article, not some magic that caused
tires to stick any better...

wrote:

For instance, while working in
the auto business, I saw testers fooled by a "power kit" that one of
two otherwise identical cars was said to have. They found it improved
acceleration out of turns and was generally better. The power kit
consisted of a lighter gas pedal return spring.

There you go! That's conclusive. Let's now state the rule - "If a
'placebo effect' exists under one set of circumstances, then it MUST
exist under any other set of circumstances where one might wish to
challenge the conclusions."

Of my three road bikes, I know unequivocally which one I would chose if
I had to chose one for the sole task of descending and/or cornering.
And it is not the one I ride most of the time, nor is it the most
exotic/expensive.
There is no question that it "handles" better than the other two, but I
have no idea which of its attributes accounts for the difference. Two
of the three were built by the same frame builder and it is one of
those two that is clearly superior in cornering security. Faster? I
don't know, not having any practical way to measure that. But more
solid feeling? Absolutely! And accordingly, I cannot discount someone's
description of a bike which corners well.

DR