Maximum cornering speed

[Travis]

I've found that I'm able to take corners much more quickly than I
previously had thought. I've braked hard thinking I'd need the whole
width of a lane at the lower speed and then found I was able to make
the turn almost sticking to the curb. Whatever my maximum cornering
speed, its a lot more than the speed I usually take corners at.

Obviously one way to find out how fast I can go around a corner is to
keep going through the corner at higher and higher speeds until I crash
and hurt myself, but I'm not keen on using this method.

What are the handling characteristics of a road bike cornering at
speed?

I've only ever felt the limits of a four wheeled vehicle, having done a
bit of autokhana (the car equivalent of criteriums I guess) and the
like. My car behaves in a fairly predictable way and I can feel
traction breaking gradually before something really bad happens (like
spinning and ending up facing the wrong way). Although I don't
generally drive the car anywhere near its limits on the road, I do
think its valuable to know what those limits are.

But never having had an opportunity (or the inclination) to safely test
the very limits of my bike, I don't know what happens. I'm allergic to
gravel you see, my skin turns red and oozy and hurts like ****
afterwards.

Do road bikes start to slide a bit at the back (oversteer), does the
front wheel just plough on and the bike runs wide (understeer), or does
something more spectacular happen, like ending up partially sideways
and then flipping over onto your head? Is the real answer "it depends
on your geometry, tires, tire pressure, road surface etc"?

Most importantly, if I am near the limits, will I feel any kind of
warning?

Travis

 

[DeF]

Travis wrote:
> I've found that I'm able to take corners much more quickly than I
> previously had thought. I've braked hard thinking I'd need the whole
> width of a lane at the lower speed and then found I was able to make
> the turn almost sticking to the curb. Whatever my maximum cornering
> speed, its a lot more than the speed I usually take corners at.
>
> Obviously one way to find out how fast I can go around a corner is to
> keep going through the corner at higher and higher speeds until I crash
> and hurt myself, but I'm not keen on using this method.
>
> What are the handling characteristics of a road bike cornering at
> speed?
>
> I've only ever felt the limits of a four wheeled vehicle, having done a
> bit of autokhana (the car equivalent of criteriums I guess) and the
> like. My car behaves in a fairly predictable way and I can feel
> traction breaking gradually before something really bad happens (like
> spinning and ending up facing the wrong way). Although I don't
> generally drive the car anywhere near its limits on the road, I do
> think its valuable to know what those limits are.
>
> But never having had an opportunity (or the inclination) to safely test
> the very limits of my bike, I don't know what happens. I'm allergic to
> gravel you see, my skin turns red and oozy and hurts like ****
> afterwards.
>
> Do road bikes start to slide a bit at the back (oversteer), does the
> front wheel just plough on and the bike runs wide (understeer), or does
> something more spectacular happen, like ending up partially sideways
> and then flipping over onto your head? Is the real answer "it depends
> on your geometry, tires, tire pressure, road surface etc"?
>
> Most importantly, if I am near the limits, will I feel any kind of
> warning?
>
> Travis
>

Two weeks ago, I came off going too fast around a
corner. For me, the front wheel went out from under
me. Previously, I have had the back wheel lose traction
on cornering (due to wear, sand etc) and have successfully
pulled it back and stayed upright.

You can improve your technique to get through corners faster.
A proper coach will tell you how but it's something like:
1. Put inside pedal up (so as to not scrape pedal)
2. Stick inside knee out as far as possible. This helps
keep the bike up right and there is a small turning torque
due to air drag on extended leg.
3. Put weight on outside half of bars (ie if turning left,
push on right side of bar).
4. Lots of things about choosing the right line etc that I
never got used to.
5. Don't wobble or grab hands full of brake.

Best advice, go slower and you won't come off, especially
if it's wet.

DeF.

--
e-mail: d.farrow@your finger.murdoch.edu.au
To reply, you'll have to remove your finger.

 

[Bleve]

Travis wrote:
> I've found that I'm able to take corners much more quickly than I
> previously had thought. I've braked hard thinking I'd need the whole
> width of a lane at the lower speed and then found I was able to make
> the turn almost sticking to the curb. Whatever my maximum cornering
> speed, its a lot more than the speed I usually take corners at.
>
> Obviously one way to find out how fast I can go around a corner is to
> keep going through the corner at higher and higher speeds until I crash
> and hurt myself, but I'm not keen on using this method.
>
> What are the handling characteristics of a road bike cornering at
> speed?

Just like with cars, motorbikes, shoes, skis ..."it depends".

Different tyres are more or less progressive with their grip, so are
different surfaces.
You don't tend to oversteer, that generally requires power to provoke,
and when cornering on a pushy, you don't have that much power
available.

>
> I've only ever felt the limits of a four wheeled vehicle, having done a
> bit of autokhana (the car equivalent of criteriums I guess) and the
> like. My car behaves in a fairly predictable way and I can feel
> traction breaking gradually before something really bad happens (like
> spinning and ending up facing the wrong way). Although I don't
> generally drive the car anywhere near its limits on the road, I do
> think its valuable to know what those limits are.
>
> But never having had an opportunity (or the inclination) to safely test
> the very limits of my bike, I don't know what happens. I'm allergic to
> gravel you see, my skin turns red and oozy and hurts like ****
> afterwards.
>
> Do road bikes start to slide a bit at the back (oversteer), does the
> front wheel just plough on and the bike runs wide (understeer), or does
> something more spectacular happen, like ending up partially sideways
> and then flipping over onto your head? Is the real answer "it depends
> on your geometry, tires, tire pressure, road surface etc"?

Yes.


>
> Most importantly, if I am near the limits, will I feel any kind of
> warning?

Maybe, it depends.

 

[dave]

Bleve wrote:
> Travis wrote:
>
>>I've found that I'm able to take corners much more quickly than I
>>previously had thought. I've braked hard thinking I'd need the whole
>>width of a lane at the lower speed and then found I was able to make
>>the turn almost sticking to the curb. Whatever my maximum cornering
>>speed, its a lot more than the speed I usually take corners at.
>>
>>Obviously one way to find out how fast I can go around a corner is to
>>keep going through the corner at higher and higher speeds until I crash
>>and hurt myself, but I'm not keen on using this method.
>>
>>What are the handling characteristics of a road bike cornering at
>>speed?
>
>
> Just like with cars, motorbikes, shoes, skis ..."it depends".
>
> Different tyres are more or less progressive with their grip, so are
> different surfaces.
> You don't tend to oversteer, that generally requires power to provoke,
> and when cornering on a pushy, you don't have that much power
> available.
>
>
>>I've only ever felt the limits of a four wheeled vehicle, having done a
>>bit of autokhana (the car equivalent of criteriums I guess) and the
>>like. My car behaves in a fairly predictable way and I can feel
>>traction breaking gradually before something really bad happens (like
>>spinning and ending up facing the wrong way). Although I don't
>>generally drive the car anywhere near its limits on the road, I do
>>think its valuable to know what those limits are.
>>
>>But never having had an opportunity (or the inclination) to safely test
>>the very limits of my bike, I don't know what happens. I'm allergic to
>>gravel you see, my skin turns red and oozy and hurts like ****
>>afterwards.
>>
>>Do road bikes start to slide a bit at the back (oversteer), does the
>>front wheel just plough on and the bike runs wide (understeer), or does
>>something more spectacular happen, like ending up partially sideways
>>and then flipping over onto your head? Is the real answer "it depends
>>on your geometry, tires, tire pressure, road surface etc"?
>
>
> Yes.
>
>
>
>>Most importantly, if I am near the limits, will I feel any kind of
>>warning?
>
>
> Maybe, it depends.
>
My experience is that yes you will feel warning. Every time you save it
Everytime you don;t there will have been no warning
How much of that is in the mind I dont know but its either "THat was
close how the hell did I save it " or "sh@# where did the bike go?"

Robbie Phyllis in an interveiw (with powered 2 wheelers ) once said. "
I was cornering really fast, knee on the deck and I thought this is
really really good then my elbow was on the deck then the side of my
helmet and I thought; if I,m not careful I will fall off here"

Dave

 

[dtmeister]

Travis <[email protected]> wrote:
>
> What are the handling characteristics of a road bike cornering at
> speed?

You may or may not have read Jobst on cornering.

http://www.sheldonbrown.com/brandt/descending.html

Obligatory picture of Jobst cornering.

http://www.sheldonbrown.com/brandt/images/tiretest.jpg

--
..dt

 

[Travis]

Bleve wrote:

> Just like with cars, motorbikes, shoes, skis ..."it depends".

I figured that would be the case.
>
> Different tyres are more or less progressive with their grip, so are
> different surfaces.
> You don't tend to oversteer, that generally requires power to provoke,
> and when cornering on a pushy, you don't have that much power
> available.

Oversteer (on a car) isn't always the result of too much power, its a
matter of weight transfer. High speed cornering in a car requires a
smooth line and gradual application of braking and power, the idea
being to avoid breaking traction by spiking the traction forces on the
tyre.

You can provoke oversteer in almost any vehicle, including front wheel
drive cars, by suddenly applying the brakes at the right point during a
turn. The result is significant weight transfer to the front and
consequently loss of grip at the back. Interestingly enough, on some
vehicles (like mine, which has a mid-mounted engine) you should
actually be applying power (though not too much) throughout a hard turn
in order to keep the weight back and PREVENT oversteer.

I've deliberately created oversteer in a variety of cars for
recreational purposes, and a truck also.

(I'd better not say too much more about cars though, considering what
happened in the speed limits thread. Lets stick to two-wheelers.)

While you're the bike coach and I'm not, I suspect that a bike too
heavily braking might experience significant weight transfer to the
front tire and hence oversteer is at least theoretically possible. No
doubt the best technique for high speed cornering doesn't involve
braking so hard you almost lift the back tire...

> > Do road bikes start to slide a bit at the back (oversteer), does the
> > front wheel just plough on and the bike runs wide (understeer), or does
> > something more spectacular happen, like ending up partially sideways
> > and then flipping over onto your head? Is the real answer "it depends
> > on your geometry, tires, tire pressure, road surface etc"?
>
> Yes.

You could also have answered "maybe" for the same instructive value...
;-)

> > Most importantly, if I am near the limits, will I feel any kind of
> > warning?
>
> Maybe, it depends.

There we go!

Ok, I take it if I want to find out what the limits are I'm going to
have to use the "go faster till I bandicoot" method?

Travis

 

[Treadly]

I've found that I'm able to take corners much more quickly than I
previously had thought. I've braked hard thinking I'd need the whole
width of a lane at the lower speed and then found I was able to make
the turn almost sticking to the curb. Whatever my maximum cornering
speed, its a lot more than the speed I usually take corners at.

Obviously one way to find out how fast I can go around a corner is to
keep going through the corner at higher and higher speeds until I crash
and hurt myself, but I'm not keen on using this method.

What are the handling characteristics of a road bike cornering at
speed?

I've only ever felt the limits of a four wheeled vehicle, having done a
bit of autokhana (the car equivalent of criteriums I guess) and the
like. My car behaves in a fairly predictable way and I can feel
traction breaking gradually before something really bad happens (like
spinning and ending up facing the wrong way). Although I don't
generally drive the car anywhere near its limits on the road, I do
think its valuable to know what those limits are.

But never having had an opportunity (or the inclination) to safely test
the very limits of my bike, I don't know what happens. I'm allergic to
gravel you see, my skin turns red and oozy and hurts like ****
afterwards.

Do road bikes start to slide a bit at the back (oversteer), does the
front wheel just plough on and the bike runs wide (understeer), or does
something more spectacular happen, like ending up partially sideways
and then flipping over onto your head? Is the real answer "it depends
on your geometry, tires, tire pressure, road surface etc"?

Most importantly, if I am near the limits, will I feel any kind of
warning?

Travis

I've noticed it's an age thing. Young people will corner a lot faster than older people, even faster if they're male, however they also tend to crash a lot more.

Treadly

 

[Random Data]

On Tue, 23 May 2006 01:40:37 -0700, Bleve wrote:

> You don't tend to oversteer, that generally requires power to provoke,
> and when cornering on a pushy, you don't have that much power
> available.

No, it requires more grip on the front than on the rear. That's a
situation that's relatively easy to achieve on a bike, by tyre choice or
rider position, and it's a lot more desirable than understeer. A touch of
rear brake will also reduce the apparent friction, since some will go to
slowing the tyre.

Ideally what you want is to be riding in such a way that you've got a very
slight tendency to oversteer. That means your rear wheel is losing
traction fractionally before your front wheel, which gives you time to
straighten up a touch and recover before you slide out. Front wheel slides
are very hard to recover from.

Two wheel drifts on a bike are interesting, as is riding crossed up (ie,
back wheel at odd angles to your direction of travel - this is possible
on a push bike if it's slippery enough). Low grip surfaces are good for
learning to control things when you break traction, so get out on really
slick concrete or some such wearing thick clothes and going slow. We used
to have competitions to see who could ride the furthest with a locked up
front wheel when it was too wet and slippery to do more fun stuff.

--
Dave Hughes | [email protected]
"Contrary to popular belief, Unix is user friendly. It just happens to
be very selective about who its friends are" -- Kyle Hearn

 

[twojaks]

Things to consider for tyre traction in corners

The first limitation is yourself, look thru the corner, head up. This will
give you the easiest and fastest cornering possible
It will smooth your approach and maximise any grip you have. Your enemy is
rapid or jerky movement, looking thru the corner means you will make less
sudden changes. Look to your exit point not at the road below you. Its'
fine to scan the road surface in the corner just don't fixate and focus on
the road 5m in front of you all the way thru or what you see will be what
you hit. It's called target fixation.

Next variable is inflation. If the tyre pressure is low you could roll off
the bead /rim and bang. Too high and the wheel skips the surface and
traction suffers. whats the right level? I dunno I don't have your tyres...

The next grip level condition is the compound of your tyre and tyre
construction. Factors that can't be generalised as every tyre manufacturer
claim to have the best compound for wet and dry surfaces, balanced with
longevity/tyre wear.

Now add the unknown which is road surface, loose gravel, sand, leaves,
camber, moisture and grease/diesel fuel.
All this means you can NEVER determine the level of grip of your tyres
except for on this tyre at this corner at this time right now.
Best you can hope for is good technique see the guide from DeF, and approach
at a speed that allows you to stop within the distance you can see.
Remeber the eyes up rule!

MJ




"Travis" <[email protected]> wrote in message
news:[email protected]...
> I've found that I'm able to take corners much more quickly than I
> previously had thought. I've braked hard thinking I'd need the whole
> width of a lane at the lower speed and then found I was able to make
> the turn almost sticking to the curb. Whatever my maximum cornering
> speed, its a lot more than the speed I usually take corners at.
>
> Obviously one way to find out how fast I can go around a corner is to
> keep going through the corner at higher and higher speeds until I crash
> and hurt myself, but I'm not keen on using this method.
>
> What are the handling characteristics of a road bike cornering at
> speed?
>
> I've only ever felt the limits of a four wheeled vehicle, having done a
> bit of autokhana (the car equivalent of criteriums I guess) and the
> like. My car behaves in a fairly predictable way and I can feel
> traction breaking gradually before something really bad happens (like
> spinning and ending up facing the wrong way). Although I don't
> generally drive the car anywhere near its limits on the road, I do
> think its valuable to know what those limits are.
>
> But never having had an opportunity (or the inclination) to safely test
> the very limits of my bike, I don't know what happens. I'm allergic to
> gravel you see, my skin turns red and oozy and hurts like ****
> afterwards.
>
> Do road bikes start to slide a bit at the back (oversteer), does the
> front wheel just plough on and the bike runs wide (understeer), or does
> something more spectacular happen, like ending up partially sideways
> and then flipping over onto your head? Is the real answer "it depends
> on your geometry, tires, tire pressure, road surface etc"?
>
> Most importantly, if I am near the limits, will I feel any kind of
> warning?
>
> Travis
>

 

[Resound]

"dtmeister" <[email protected]> wrote in message
news:[email protected]...
> Travis <[email protected]> wrote:
>>
>> What are the handling characteristics of a road bike cornering at
>> speed?
>
> You may or may not have read Jobst on cornering.
>
> http://www.sheldonbrown.com/brandt/descending.html
>
> Obligatory picture of Jobst cornering.
>
> http://www.sheldonbrown.com/brandt/images/tiretest.jpg
>
> --
> .dt

I really wonder about Jobst's take on cornering. He's convinced that leaning
out from the bike in any way not only doesn't help but is detrimental to
cornering and illustrates this with a couple of rather odd thought
experiments. I can't really see a bicycle being so radically different to a
motorbike in cornering behavious though. What do the motorcyclists here
think? I can't really offer too many opinions of my own other than front
losing grip seems more likely and from my own experience, more common than
losing grip at the rear. Also, if the rear slides/locks it's usually a
doddle to save because you can still steer. When the front goes you're
probably going down because you can't steer. But I'm a cornering wuss.

 

[flyingdutch]

gee. it's real easy to pick those who have never ridden a motorbike. fast.

I'm in the middle (hopefully) of a roadbike-handling-****-phase
(accident, bad head-space, etc, etc insert more excusues here...)

Oversteering is 'the devil'. It achieves nothing and is far more likely to cause balzing things up.
The sooner you lose the instinct to steer the bike and and start to 'control your direction', the sooner you wil lbecome a Salvodelli

Counter-steering is a black art to get your head around but once nailed is laughably easy and silly-simple.
STOP thinking as if you have a 'steering wheel' and can point your arms/shoulders/bars into a corner and start thinking weight transfer.

A motorbike pushes this theory to the limit cos you are working 'against' ALOT of weight. you have no choice but to 'fight it', If you ever see footage of Gardiner at his peak, you'l lget what I'm talking about. He climbed all over the thing!

Inside shoulder FORWARD, outside foot forcing down, lean the bike BUT NOT you! (ie you go the other/outer side...)

DO NOT try to 'point' the wheel into/around the corner on fast corners. great way to end up in the shrubbery/kitty-litter...

 

[Aeek]

On Tue, 23 May 2006 21:10:06 +1000, flyingdutch
<[email protected]> wrote:

>Inside shoulder FORWARD, outside foot forcing down, lean the bike BUT
>NOT you! (ie you go the other/outer side...)
>
>DO NOT try to 'point' the wheel into/around the corner on fast corners.
>great way to end up in the shrubbery/kitty-litter...

Lean the bike to turn and let the front do what it wants! My arms are
passive shock absorbers. Maybe I countersteer? Don't really know, I am
looking ahead, not at my bike.

I don't see paint or even oil as an issue, but gravel, at its worst,
can't brake, can't turn, can drift (barely). FUN or pain.
Andre

 

[rooman]

• relax...
• 'know your proper line and nail it....
• look ahead out of the turn...( where you look you will end up )
• keep shoulder forward to weight front wheel and outside foot fully extended down and pressed hard on outside pedal to lower centre of G.

practice, practice, practice....build up speed with practice and confidence...

you will improve....as some smarty once said "it may not happen over night but it will happen"

practice...practice...practice

bike handling is a craft...become a crafts(wo)man...its not about nerve its about skill and practicing to develop that skill...

enjoy the journey, as there is no destination, it just gets better and better

 

[Kim Hawtin]

Resound wrote:
> dtmeister wrote
>>Travis wrote:
>>>What are the handling characteristics of a road bike cornering at
>>>speed?
8<
>>Obligatory picture of Jobst cornering.
>>
>>http://www.sheldonbrown.com/brandt/images/tiretest.jpg
8<
> I really wonder about Jobst's take on cornering. He's convinced that leaning
> out from the bike in any way not only doesn't help but is detrimental to
> cornering and illustrates this with a couple of rather odd thought
> experiments. I can't really see a bicycle being so radically different to a
> motorbike in cornering behavious though. What do the motorcyclists here
> think?

/me babbles ... center of gravity is higer on a bicycle than a
motorbike. my take on it was keeping the CoG in the middle of the bike
meant you could get the bike lower. there simply isn't enough rubber on
the narrow tire of a roadie to lean over more than about 45o. well, my
gators get very exciting about then anyways... the other end of the
stick is to get outa the saddle and lean your body over lots so that the
bike is more upright and the CoG is lower, but then its a hand-eye
steering coordination thing 'cause the dynamics are different and arms
in different places. its just practice, but you fsck it up the first
time =) i remember that going very badly once, down hill at speed, very
heavy panniers etc skin deformation etc

> I can't really offer too many opinions of my own other than front
> losing grip seems more likely and from my own experience, more common than
> losing grip at the rear. Also, if the rear slides/locks it's usually a
> doddle to save because you can still steer. When the front goes you're
> probably going down because you can't steer. But I'm a cornering wuss.

on my roadie the rear is far more likely to go.
however on the fixie its pretty much always the front.
have only a front brake on both bikes. main thing is the fixie has a
much more upright riding position, and i expect large percentage of
weight on the rear.

however on my mtb, sh*t happens, everywhich way. have had many many
offs, mainly involving white lines and dampness and speed.

seems to me that if you want consistent behaviour, you'd want the rear
to go first, then you'll need to setup the weight distribution for that,
ie more weight to the front, so a longer wheelbase frame would help, and
guess where those panniers need to be? hmmm so trikes are out =/

cheers,

kim

 

[Peter Signorini]

"Aeek" wrote:
> flyingdutch wrote:
>
>>Inside shoulder FORWARD, outside foot forcing down, lean the bike BUT
>>NOT you! (ie you go the other/outer side...)
>>
>>DO NOT try to 'point' the wheel into/around the corner on fast corners.
>>great way to end up in the shrubbery/kitty-litter...
>
> Lean the bike to turn and let the front do what it wants! My arms are
> passive shock absorbers. Maybe I countersteer? Don't really know, I am
> looking ahead, not at my bike.

This is the big difference between bicycles and motorbikes in the whole
countersteer thing. A bicycle can be leaned easily by a small body move by
the rider as the riders weight is such a great proportion of the total mass.
It's a lot harder for a motorbiker to shift a 300kg motorbike.

Once you look into the corner, lean the bike, then the wheel drops with the
castor effect, and you're turning. Countersteering is another way to do it,
I've tried it, it works quite quick, but it's not what I do in a typical
smooth turn. Maybe a strategy for some sort of emergency turn.

Now I'll put on my flame-proof suit

--
Cheers
Peter

~~~ ~ _@
~~ ~ _- \,
~~ (*)/ (*)

 

[Peter Signorini]

"Resound" wrote:

> I really wonder about Jobst's take on cornering.

Yes, and this:
It is often said that putting the outside pedal down in a curve improves
cornering. Although most experienced riders do this, it is not because it
has anything to do with traction. The reason is that it enables the rider to
unload the saddle while standing with little effort on a locked knee,
cushioning his weight on his ankle. This can only be done on the outside
pedal because the inside pedal would hit the road. However, standing on one
extended leg does not work on rougher roads, because the ankle cannot absorb
large road bumps nor raise the rider high enough from the saddle to avoid
getting bounced. Rough roads require rising high enough from the saddle to
avoid hard contact while the legs supply shock absorbing knee action, with
pedals and cranks horizontal.
This has not been ny experience descending rough gravel mountain roads on a
loaded MTB. Put the pedal down, put lots of weight on it, even while still
seated on the saddle, and the bike turns *much more promptly* than if you
hold the cranks level. It actually seems to follow the track like it's on
autopilot.

I can only guess that Jobst doesn't ride wide knobby tyres down dirt and
gravel roads very much. From reading some of his stuff he seems to be more
of a road/cyclocross rider. Wider tyres give you that extra traction that
allows greater control in turns on dirt.
--
Cheers
Peter

~~~ ~ _@
~~ ~ _- \,
~~ (*)/ (*)

 

[Bleve]

Random Data wrote:
> On Tue, 23 May 2006 01:40:37 -0700, Bleve wrote:
>
> > You don't tend to oversteer, that generally requires power to provoke,
> > and when cornering on a pushy, you don't have that much power
> > available.
>
> No, it requires more grip on the front than on the rear. That's a
> situation that's relatively easy to achieve on a bike, by tyre choice or
> rider position, and it's a lot more desirable than understeer. A touch of
> rear brake will also reduce the apparent friction, since some will go to
> slowing the tyre.

That would only happen if you were braking through the corner, or doing
something quite odd with body english.
Usually, this is not a wise cause of action. (Trav, I rallied for many
years and have flung cars sideways around a lot of corners & I
understand. My dad rallied a renault 10, rear engine, more taily on
liftoff than an old 911 ... ) I would *not* attempt this on a bicycle
on the road!

> Ideally what you want is to be riding in such a way that you've got a very
> slight tendency to oversteer. That means your rear wheel is losing
> traction fractionally before your front wheel, which gives you time to
> straighten up a touch and recover before you slide out. Front wheel slides
> are very hard to recover from.
>
> Two wheel drifts on a bike are interesting, as is riding crossed up (ie,
> back wheel at odd angles to your direction of travel - this is possible
> on a push bike if it's slippery enough). Low grip surfaces are good for
> learning to control things when you break traction, so get out on really
> slick concrete or some such wearing thick clothes and going slow. We used
> to have competitions to see who could ride the furthest with a locked up
> front wheel when it was too wet and slippery to do more fun stuff.

He's on a roadbike, riding on bitumen. If it was an MTB on dirt, I'd
agree with you.

 

[Zebee Johnstone]

In aus.bicycle on Tue, 23 May 2006 22:36:16 +1000
Peter Signorini <[email protected]> wrote:
>
> Once you look into the corner, lean the bike, then the wheel drops with the
> castor effect, and you're turning. Countersteering is another way to do it,
> I've tried it, it works quite quick, but it's not what I do in a typical
> smooth turn. Maybe a strategy for some sort of emergency turn.

With a motorcycle, the quick transition from upright to leaned over is
one of the secrets of speed. You go a bit deeper in before you start
the transition, and push hard on the inside bar to drop the bike down
quickly.

One consequence of this is that you don't have to lean over as far for
a given corner and speed. So you can increase the speed for the same
angle of lean.

It does require acceleration through the corner and drive out of it, I
have no idea how well that can be done when you have to worry about
pedals hitting the ground.

I haven't had an opportunity to do fast cornering on the bent, be
interesting to see what the mechanics are there. As I don't have to
worry about pedal clearance, if the speed's high enough that it's all
countersteer then leg clearance should be fine so I should be able to
turn it like a motorcycle.

Zebee

 

[ritcho]

"Resound" wrote:

> I really wonder about Jobst's take on cornering.

[snip]

I can only guess that Jobst doesn't ride wide knobby tyres down dirt and
gravel roads very much. From reading some of his stuff he seems to be more
of a road/cyclocross rider. Wider tyres give you that extra traction that
allows greater control in turns on dirt.
--
Cheers
Peter

~~~ ~ _@
~~ ~ _- \,
~~ (*)/ (*)

I reckon you're right about Jobst being more of a road rider. A road bike with narrow, high pressure tyres is very difficult to control once traction is disrupted. If the front slides, you'll most likely crash and if the back slides, you'll nearly as likely crash. I've found the key to cornering quickly on a road bike is just to choose the right line (i.e., the widest radius curve that will fit in the road).

Ritch

PS. You don't _always_ crash. The other day I had a cheek-clenching moment on the fixie when I was reminded that pedal-strike is a Bad Thing. The back wheel was levered off the ground and lean angle increased as the bike turned on the pedal. The front tyre managed to squirm and maintain traction as the rear wheel returned to earth and also gripped... phew(!). I now have a nice big grind on the right pedal... cool!

 

[Zebee Johnstone]

In aus.bicycle on Tue, 23 May 2006 21:08:37 +1000
Resound <sacredchao@> wrote:
> experiments. I can't really see a bicycle being so radically different to a
> motorbike in cornering behavious though. What do the motorcyclists here
> think? I can't really offer too many opinions of my own other than front

I think it's about traction.

In the old days when tyres weren't that good, motorcyclists didn't
hang off. They stayed on the bike and tidy so as not to upset it with
body movements because they couldn't lean the bike so far it grounded.

Hanging off didn't start until tyres were good enough that the problem
was grounding bits not losing traction.

And once the tyres got good but the chassis got better, they stopped
hanging off again (eg that famous pic of Hailwood on the Honda 6).
They leaned the bike over to the tyre's limit but there was nothing
grounding so no need to hang off.

NOwadays tyres stick like the proverbial to a blanket and you can get
the things damn near horizontal, so they hang off again for the ground
clearance.

Bicycle tyres don't have a lot of contact patch, so they are more
easily convinced to lose traction than motorcycle tyres.

GIven the pedal clearance problems, a rider could hang off to lean
over more but I think ergonomically it would be silly And if you
don't get over far enough to make a difference to the centre of
gravity then no point getting over at all. Especially considering the
interruption to smooth pedalling.

Zebee