Weight shifting for corners

[Tim Cullis]

This sort of continues on from the threads on countersteering on the R12GS and rear brake for tight corners.

JayGee commented

what I think I do on the GS is diliberately counter steer almost always and I lean the bike more than myself. I'm not sure this is a good technique as I was always told to lean into the bend with my body and this will reduce the lean angle of the bike but I seem to be doing the opposite on the GS.

I often find myself doing the same as JayGee (leaning the bike more than myself) especially when flipping through roundabouts.

But I'm aware that on the track riders always shift their bums on the seats so they are the ones doing the leaning, thus minimising the lean of the actual machine.

Why do they do this? Does it somehow improve the cornering ability, or is it so they don't scrape the pegs?

Tim

 

[Deleted account 211025001]

Yeah Tim, I'm the same as you and am often 'more upright' than the bike when cornering - a bit of a hang over from Supermoto days when I'd 'push' the bike down below me when cornering hard IYSWIM.

The reason for getting your bum off the seat is, as you state, not to have to lean the bike over so much as you would if you asumed the Body English position.

It's pretty much pointless on the road but when racing every little last mm of tyre contact patch is needed so if you don't need to lean the bike as much for a given corner speed it follows that you can get around a corner that little bit faster for a give bike lean angle.

Reading back I'm not sure if the above is very clear, I know what I mean any way

HTH
Andres

 

[Tim Cullis]

Yes, 'push down' is what I was thinking of.

The other time when I've been told to shift my bum (by my IAM observer) is for slow speed manoeveurs. I must remember to ask why.

Tim

 

[Kropotkin]

But I'm aware that on the track riders always shift their bums on the seats so they are the ones doing the leaning, thus minimising the lean of the actual machine.

The reason that track riders "hang off" the bike is two-fold:

1. It shifts the centre of gravity of the bike to the inside of the bike (by inside, I mean inside of the turn), which means they have to lean the bike over less to make the turn at a particular speed. If you have to lean the bike over less, you have more tyre to lean on, so more grip. Though in practice, what you want to do is go faster. So racers hang off the bike, with the bike at the same angle as if they were not hanging off, but faster, IYSWIM.

If you watch the real elite, you will see them hanging off, but at the same time, the bike is leaned over so far, they are actually having almost to pull their knee back in to fit it in the space.

2. Less lean angle = more ground clearance. Which means you can go faster next time round....

For very short turns (such as roundabouts), you are actually better off riding in a motorcross style, i.e. body upright, and pushing the bike down, as you can do this more quickly than clambering from one side of the bike to the other. But the upright seating position, and the wide bars, make the GS much easier to ride "motorcross style" than racing style. I tend to "chuck" the bike around, with the bike leaning over more than me, except in some very long turns. The wide bars and upright position is also what makes the bike so much fun to ride ....

 

[Deleted account 211025001]

Re: Re: Weight shifting for corners

The reason that track riders "hang off" the bike is two-fold:

1. It shifts the centre of gravity of the bike to the inside of the bike (by inside, I mean inside of the turn), which means they have to lean the bike over less to make the turn at a particular speed.

-snip-

So much more succinct - just what I was trying to say

Andres

 

[Mouse]

Yes, 'push down' is what I was thinking of.

The other time when I've been told to shift my bum (by my IAM observer) is for slow speed manoeveurs. I must remember to ask why.

Tim

I think that your IAM chap is referring to is what some people call "counterweighting". Basically you shift your weight to the outside of the turn, to allow you to lean the bike further but still keep the centre of gravity central.

It's an excellent way of doing really tight, full lock, turns - U turns for example. Takes a bit of getting used to and apparently it's rather disconcerting for pillion passengers

I only use counterweighting at very slow speeds, but it's similar to the technique that motocross and speedway riders use at much higher speeds.

 

[Tim Cullis]

you shift your weight to the outside of the turn

Woops, that explains why I have had problems trying to replicate this since. I have been shifting to the inside!

Tim

 

[Gipsy]

Countersteering is something that we all do to go round corners other than at low speeds when 'real time' steering kicks in. It makes sense to practice it and use it as a skill, as it can dramatically improve one's riding. As an aside quick countersteering ( pushing/pulling the bars firmly ) actually decreases the lean angle you use to complete your turn. I know it sounds a bit bizarre, but its true. The California Superbike School explained it all, and it made sense at the time. This goes part way to explain why racers seem to ' bang the bikes over ' very quickly. It means they spend less time on the edge of the tyre where grip is least, and hanging off merely allows them to use less lean angle for a given speed hence increasing the tyre contact patch. The ease with which the GS bars appear to counter steer is due to the long leverage they allow together with the excellent ergonomics of the riding position allowing the force to be applied correctly. Sports bike riders in a racing crouch are in the correct riding position for a sports bike and in that case countersteering a sports bike is just as easy as the GS. Mainly however sports bikes aren't ridden on the rodes in the crouch position. In those circumstances forearms aren't parallel to the ground, and an element of downward force is being applied to the bars, and not just a straight push or pull.
One other advantage of quick countersteering is that even in wet conditions it lessens the time time spent leant over, and allows a greater contact patch. There I've finished and I'm off to lie down. It may all sound like a piece of bullshit, but if there are any other members out there who have attended the California Superbike School, I think they will back me up, and may even be able to give a far better explanation of the effect.

 

[Droopy Dick]

I think that your IAM chap is referring to is what some people call "counterweighting". Basically you shift your weight to the outside of the turn, to allow you to lean the bike further but still keep the centre of gravity central.

.

Is it not also because,a s with weghting the outside footpeg, the pressure means that the gyroscopic forces on the wheels mean they will in fact lean tighter into the bends?

It's the old 'action/reaction ar equal but opposite' but when applied to gyroscopes (i.e. wheels that are turning) the reaction is applied at a point 90 degs further round in the direction of rotation. If that makes sense. It's the reason why you fall into the turn when you apply the forces on the handlebars, and incidentally why counter-steering works once the lean is initiated.

 

[Ming]

Absolutley bang on !! ya pikey git!!