Get a Grip Cornering

[si_c]

I'm more of a straight line merchant. Going fast around bends I always seem to be envisioning the front wheel going from under me. Maybe I should pay more attention to @Ajax Bay 's analysis...get it over to 40+ degrees and rely on the immutable laws of Physics

That'd work, remember at angles less than 45 degrees you are still developing the same contact point on the road, so if you shift your weight out to the outside of the corner to maintain the same relative centre of gravity over the contact point you can angle the bike further. Moving the angle beyond 45 degrees the angle of forces on the road are no longer perpendicular but parallel which is what causes the tyre to skate off. This of course assumes dry surfaces.

Edit: This is why velodrome corners are banked and we have berms on MTB trails, it reduces the relative angles between bike and road allowing faster cornering.

 

[Ajax Bay]

remember at angles less than 45 degrees you are still developing the same contact point on the road, so if you shift your weight out to the outside of the corner to maintain the same relative centre of gravity over the contact point you can angle the bike further. Moving the angle beyond 45 degrees the angle of forces on the road are no longer perpendicular but parallel which is what causes the tyre to skate off.

"remember at angles less than 45 degrees you are still developing the same contact point on the road" - I don't know what you mean to mean by this.
"so if you shift your weight out to the outside of the corner to maintain the same relative centre of gravity over the contact point you can angle the bike further." This is true but the 'grip lost' angle is the angle from the normal to the ground (ie 90 degrees to the surface - banking will affect this) to the line joining the line on the ground joining the two tyre contact areas and the centre of gravity of the bike/rider combo. It doesn't matter where you hang your a**e, the angle that matters (CoG to ground v ground normal) is still the same.
"Moving the angle beyond 45 degrees the angle of forces on the road are no longer perpendicular but parallel which is what causes the tyre to skate off."
Not sure I really get that. The tyre's not 'skating off': when grip's lost the tyres just carries on in the direction they were going.
If you lean more than 45 degrees, the weight of the rider/bike still presses down against the road and the normal force still operates directly upwards (hopefully through the tyre contact areas!). But at 45 degrees lean (let us assume that that's the 'let go' point/angle), the frictional force implied is the same as the normal force and the coefficient of friction between the rubber and the road is not sufficient and cannot deliver the sideways (centripetal) force to keep the bike/rider going round the corner, so the bike/rider combo proceeds with the velocity it had at the point of 'let go' and the riders body will cease to enjoy the force that keeps him/her above ground level . . .
HTH
Here's hoping for a higher than expected coefficient of friction when it's most needed this winter, a dose of prudence and a wedge of luck (partly self-made).

 

[andrew_s]

I would reiterate that the 45 deg limit wasn't actual real cornering, but an upright bike on sloping tarmac. It ought to be the same for when slip occurs, but obviously the consequences of slip aren't the same.
This well known photo is the best I'm aware of as far as photographic evidence is concerned

On a personal basis, I think the furthest over I've been was a fairly solid grounding of the inside pedal, back when I rode fixed regularly. Ironically, I most frequently grounded the pedal when on gears, which I put down to subconsciously thinking that since I was on gears, I didn't have to worry, but still being in the habit of pedaling through corners. It's not recommended - the pedal goes round regardless, and the back wheel gets lifted off the road and dropped back.

 

[ColinJ]

I think that I probably do sometimes lean my bike as much as the bike in nickyboy's photo, but definitely not with the inside pedal down!

I rode about 30 miles of the Manchester 100 once with someone I got chatting to who was riding fixed. I was seriously impressed by how fast he was cornering considering that he had to keep pedalling the whole time! (I assume that fixed gear bikes have shorter cranks and/or higher bottom brackets to reduce the chances of pedals striking the ground?)

Oh, I came across a picture of a pair of my pedals ...

The tops of the pedals:

And the bottoms of the pedals [Hint - look closely at the one on the left! ]:

 

[Yellow Saddle]

I would reiterate that the 45 deg limit wasn't actual real cornering, but an upright bike on sloping tarmac. It ought to be the same for when slip occurs, but obviously the consequences of slip aren't the same.
This well known photo is the best I'm aware of as far as photographic evidence is concerned

On a personal basis, I think the furthest over I've been was a fairly solid grounding of the inside pedal, back when I rode fixed regularly. Ironically, I most frequently grounded the pedal when on gears, which I put down to subconsciously thinking that since I was on gears, I didn't have to worry, but still being in the habit of pedaling through corners. It's not recommended - the pedal goes round regardless, and the back wheel gets lifted off the road and dropped back.

The slip-out angle is always measured relative to the road and the horizon never comes into it.
That photo is of Jobst Brandt whilst testing tyres for Avocet, a company owned by his friends. They employed his as engineer and tribologist on the project and he first tested the tyres on rolling steel drums and then confirmed his findings on the road. That is 45 Degrees. The tyres were Avocet carbon black tyres.

The company still has a website but it hasn't changed in years and I doubt it still trades. Jobst died last year.

 

[raleighnut]

I would reiterate that the 45 deg limit wasn't actual real cornering, but an upright bike on sloping tarmac. It ought to be the same for when slip occurs, but obviously the consequences of slip aren't the same.
This well known photo is the best I'm aware of as far as photographic evidence is concerned

On a personal basis, I think the furthest over I've been was a fairly solid grounding of the inside pedal, back when I rode fixed regularly. Ironically, I most frequently grounded the pedal when on gears, which I put down to subconsciously thinking that since I was on gears, I didn't have to worry, but still being in the habit of pedaling through corners. It's not recommended - the pedal goes round regardless, and the back wheel gets lifted off the road and dropped back.

Shame he's on a 'banked' corner

The slip-out angle is always measured relative to the road and the horizon never comes into it.
That photo is of Jobst Brandt whilst testing tyres for Avocet, a company owned by his friends. They employed his as engineer and tribologist on the project and he first tested the tyres on rolling steel drums and then confirmed his findings on the road. That is 45 Degrees. The tyres were Avocet carbon black tyres.

The company still has a website but it hasn't changed in years and I doubt it still trades. Jobst died last year.

And if that is 45 degrees remind me never to ask you to cut a mitre, it's close but no cigar.