Does leaning increase the limit of cornering speed?

**Rodney007** · 28th February 2009, 18:42

Hi guys, seem to be caught up in a little arguement, with a guy prolly in mid 40's that claims i am a "little shitbag" because i stated that:

leaning off your bike through a corner will allow the bike to go around the corner at less of a angle AT THE SAME SPEED, and allows your body to act as a ballast, increasing the contact path of your tyre (and all the other technical stuff) thus allowing you to go around the corner FASTER than if you simply stayed central on the bike.

i dont mean it boosts your speed, i mean does it increases the corning ability of rider/bike.

if anyone can simply say they agree or disagree it would be MUCHLY appreciated as this guys going off the hook at me. and il point him here to have a read THANKS!

**MisterD** · 28th February 2009, 18:44

Originally Posted by Rodney007

Hi guys, seem to be caught up in a little arguement, with a guy prolly in mid 40's that claims i am a "little shitbag" because i stated that:

leaning off your bike through a corner will allow the bike to go around the corner at less of a angle, and allows your body to act as a ballast, increasing the contact path of your tyre (and all the other technical stuff) thus allowing you to go around the corner FASTER than if you simply stayed central on the bike.

if anyone can simply say the agree or disagree it would be MUCHLY appreciated as this guys going off the hook at me. and il point him here to have a read THANKS!

Yes, it's physics and I have a degree in that stuff, and I'm 38.

**TimeOut** · 28th February 2009, 19:00

Agree

**Badger8** · 28th February 2009, 19:01

Yup, simple physics mate! And if you dont believe it, give it a try!

The more weight you shift to the inside of the corner (and the higher up the weight the bigger the difference), the more upright the bike will be whilst cornering at the same speed. This is good as your suspension will be more in line to absorb any bumps in the road etc as you corner, and you've got more grip if it's damp etc. Could go on about the benefits.
The added effect is, if you are moving your weight off, you now have the ability to go faster round this same corner as you have more lean available.

e.g. you could go around a corner upright on the bike peg down (NOT recommended!), or hanging some weight off the bike, bike more upright, at the same speed.
The flipside being you have more lean available, so now if you go to 'peg-down-lean' and hanging off, you are going a lot faster around the given corner. Watch a racer giving it stick on the track and see it in action

**MisterD** · 28th February 2009, 19:05

...and the tin-lid on the argument: watch the GP riders, they do it and they wouldn't if it didn't work...

**Rodney007** · 28th February 2009, 19:35

cheers keep it flowin!

**reofix** · 28th February 2009, 19:44

just one little problem .... on the road we are never approaching the limits of cornering so hanging out on the low side is just posing... hang out on the high side and you find you can see twice as far ahead... safe stopping distance is preserved... you get to live longer

**Rodney007** · 28th February 2009, 19:53

Originally Posted by reofix

just one little problem .... on the road we are never approaching the limits of cornering so hanging out on the low side is just posing... hang out on the high side and you find you can see twice as far ahead... safe stopping distance is preserved... you get to live longer

yah your very right,
im more so refering to riding on the track, but the basic rule of leans apply's either way,

**erik** · 28th February 2009, 20:04

Originally Posted by Rodney007

... increasing the contact path of your tyre (and all the other technical stuff

The other stuff was accurate, but I don't know about it increasing the tyre's contact patch, that'd depend on the profile of the tyre.

Originally Posted by Badger8

...The more weight you shift to the inside of the corner (and the higher up the weight the bigger the difference), the more upright the bike will be whilst cornering at the same speed.

Actually, the lower the weight, the more effect it would have. For the same mass, if you moved it 200mm to the side of the bike's centreline, the angle between the mass and the bike's centreline (centred on the tyre's contact patch) would increase as you move the weight lower.

But yeah, if you're running out of cornering clearance (ie pegs etc are scraping), hanging off the bike (actually, I'd say it feels more like holding the bike more upright than hanging off it) will give you more cornering clearance and you can then go a little faster.

**Mikkel** · 28th February 2009, 20:09

If you leave the contact patch stuff out I would have to agree.

In order to achieve the highest possible cornering speed you'd have to hang off your bike (provided your tyres are sticky enough of course) - otherwise you'll be touching down footpegs, rocker covers, fairings, handlebars and wing mirrors before you get the maximum rate of turn.

**Badger8** · 28th February 2009, 20:17

Originally Posted by erik

Actually, the lower the weight, the more effect it would have. For the same mass, if you moved it 200mm to the side of the bike's centreline, the angle between the mass and the bike's centreline (centred on the tyre's contact patch) would increase as you move the weight lower.

But yeah, if you're running out of cornering clearance (ie pegs etc are scraping), hanging off the bike (actually, I'd say it feels more like holding the bike more upright than hanging off it) will give you more cornering clearance and you can then go a little faster.

Dont forget we're talkin about when the bike is already tipped over a reasonable bit, so higher up weight is already inside the centre of mass

I find for myself that moving my butt and keeping my torso over the tank has bugger all effect, but leaving my butt central and moving my shoulders out makes a huge difference

Certainly does feel like holding the bike more upright. I find when i transition my weight it feels almost like i'm pushing the bike under me rather than me moving over the bike. That may have something to do with the ratio of my weight to the bikes weight tho...

**Rodney007** · 28th February 2009, 20:21

Originally Posted by Mikkel

If you leave the contact patch stuff out I would have to agree.

In order to achieve the highest possible cornering speed you'd have to hang off your bike (provided your tyres are sticky enough of course) - otherwise you'll be touching down footpegs, rocker covers, fairings, handlebars and wing mirrors before you get the maximum rate of turn.

fair enough , i thought putting weight over where the tyre is making contact with the surface would possibly spread it a bit,

thats error on my part.

**Badger8** · 28th February 2009, 20:23

Originally Posted by Rodney007

fair enough , i thought putting weight over where the tyre is making contact with the surface would possibly spread it a bit,

thats error on my part.

Depends on your tyre profile mate, so may or may not be true dependant on the specifics

**Mikkel** · 28th February 2009, 20:28

Originally Posted by Rodney007

fair enough , i thought putting weight over where the tyre is making contact with the surface would possibly spread it a bit,

thats error on my part.

Leaning may change the shape of the contact patch. Not the size.

The faster you're going around the corner the more force the bike applies to the road and consequently the size of the contact patch increases - but it is not due to the lean.

I must say most comments that I have seen about the contact patch have been utter bollocks and I'd personally recommend forgetting everything about that term. It is purely academic. Tyre compound, profile and pressure are the only things I would concern myself with. The priority would be: pressure, compound and then profile IMO.

**Skyryder** · 28th February 2009, 20:28

Essentially you are correct. I think ballast is wrong. Basically by leaning 'off' your bike you are lowering your centre of gravity (mass) further than if you did not lean and just stayed in the same line/angle as the bike. Not too sure of the physics involved on this. Try googling this.

Skyryder