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40% - 60% Split


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Another question about throttle control!

 

We all know that when cornering we are aiming to achieve the bikes weight distribution at 40% front and 60% rear but how do you know if you are achieving the correct split?

Would more or less than 60% at the rear be better, e.g would more throttle giving say 65% rear be better than less and 55% at the rear? Also would a road bike require more throttle than a track bike to achieve the same weight distribution taking into consideration all the heavy equipment (lights, wiring, and switch gear) sitting over the front end of a road bike?

 

Let me know what you guys think!

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Another question about throttle control!

 

We all know that when cornering we are aiming to achieve the bikes weight distribution at 40% front and 60% rear but how do you know if you are achieving the correct split?

Would more or less than 60% at the rear be better, e.g would more throttle giving say 65% rear be better than less and 55% at the rear? Also would a road bike require more throttle than a track bike to achieve the same weight distribution taking into consideration all the heavy equipment (lights, wiring, and switch gear) sitting over the front end of a road bike?

 

Let me know what you guys think!

Keith on T of T2 page 6 indicates that "each bike's exact ideal weight distribution may vary a bit from the basic 40/60 percent rule."..... and on page 7 " it is the feeling of 0.1 to 0.2 G acceleration....... which is a smooth fifth-gear roll-on in the 4000 to 6000 rpm range on pretty much anything over 600CC."

Cornering to me is at least 3 parts: leaning to the angle..... maintain lean angle....... accelerating out of lean angle.

It seems the 40/60 is applied to the "maintain lean angle"; just right before countersteering and "leaning to the angle", if with just little more weight at front by throttle-off, it seems allow tighter quick turn or hook turn. When combined with good timing of maintanence throttle right with leaning, there is less disturbance to suspension. Anyone see it differently?

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Keith on T of T2 page 6 indicates that "each bike's exact ideal weight distribution may vary a bit from the basic 40/60 percent rule."..... and on page 7 " it is the feeling of 0.1 to 0.2 G acceleration....... which is a smooth fifth-gear roll-on in the 4000 to 6000 rpm range on pretty much anything over 600CC."

 

.1g is not the same as 1.1g. 1.0g is equilibrium. In order to have 10% weight shifted to the rear one would have to have a force (forward drive) above 1g, hence 1.1-1.2g.

 

Cornering to me is at least 3 parts: leaning to the angle..... maintain lean angle....... accelerating out of lean angle. It seems the 40/60 is applied to the "maintain lean angle"; just right before countersteering and "leaning to the angle", if with just little more weight at front by throttle-off, it seems allow tighter quick turn or hook turn. When combined with good timing of maintanence throttle right with leaning, there is less disturbance to suspension. Anyone see it differently?

 

I noticed that lately Cobie has been a bit repetitive, almost mantra-like with gentle warnings of adding lean angle and throttle simultaneously. It would seem to me that removing lean angle and adding throttle as suggested by your "accelerating out of lean angle" statement would be just as perilous, as they are both done by a countersteering input. Remember, the throttle does not cause the bike to stand up.

 

If I am incorrectly applying Cobie's warning to picking the bike up, then I am open for correction (more on this in the last paragraph).

 

Engineers are constantly tweaking the Center of Gravity (CoG ) on bikes and the current trend is toward an increased forward weight bias. Does this in itself allow harder acceleration, as one would need to transfer more weight in order to reach Mr. Code's stated goal of 60% on the rear?

 

Maintaining lean angle isn't something the rider must do, rather than something the rider must NOT do. He must NOT change the lean angle once established during mid-corner. The roll of the right wrist arrests the lean angle and adds stability (resistance to change) to the machine. That's it.

 

In conclusion, I agree with you in that high-performance cornering is 3 inputs:

1- Countersteer

2- Roll on the throttle during mid-corner

The force applied during this rolling action must not exceed the available traction of the front tire that will be needed during cornering, with enough reserve to stand the bike to vertical

3- Countersteer to vertical while continuing to feed throttle

The limit of the rate of roll is now higher because of what is now available from continually reduced side loads

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.1g is not the same as 1.1g. 1.0g is equilibrium. In order to have 10% weight shifted to the rear one would have to have a force (forward drive) above 1g, hence 1.1-1.2g.

 

This doesn't make sense to me. My idea of 1g is that it is simply a representation of the acceleration of gravity. So the only time 1g is equilibrium is when an object is not moving and the reason it's not moving is because the ground is providing enough force to counter the acceleration of gravity - we'll exclude earth rotational, and other larger scale movements for the sake of simplicity.

 

For an object to change it's speed, whether that speed is 0mph or 100mph, a force must be applied to cause acceleration. The resultant acceleration need not be greater than 1g unless we are talking vertical acceleration. For road racing motorcycles, vertical acceleration is generally a bad thing.

 

I think the 0.1g is correct. 1g, 32/ft/sec/sec, is a lot of forward acceleration.

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.1g is not the same as 1.1g. 1.0g is equilibrium. In order to have 10% weight shifted to the rear one would have to have a force (forward drive) above 1g, hence 1.1-1.2g.

 

This doesn't make sense to me. My idea of 1g is that it is simply a representation of the acceleration of gravity. So the only time 1g is equilibrium is when an object is not moving and the reason it's not moving is because the ground is providing enough force to counter the acceleration of gravity - we'll exclude earth rotational, and other larger scale movements for the sake of simplicity.

 

For an object to change it's speed, whether that speed is 0mph or 100mph, a force must be applied to cause acceleration. The resultant acceleration need not be greater than 1g unless we are talking vertical acceleration. For road racing motorcycles, vertical acceleration is generally a bad thing.

 

I think the 0.1g is correct. 1g, 32/ft/sec/sec, is a lot of forward acceleration.

 

You are correct in that 1g is too much in the forward component. (What in the world was I thinking....)

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Hmmm... So the 60/40 rule is 60% of the weight on the rear? Really?

 

according to TOTW2 this is the case!

The distribution of cornering loads follows your tire's contact patch size- about 40% front to 60% rear, you adjust the tire load with the throttle.

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Hmmm... So the 60/40 rule is 60% of the weight on the rear? Really?

Ultimately you're going to end up with 40/60% ratio, or there about. You've got to get on the gas. If you go into the corner as heavily as when you initially start dipping the bike, you're going to lowside. Next trackday pay attention during a big carousel, or something similar. You're on the gas, and this means you've got more weight on the back.

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I noticed that lately Cobie has been a bit repetitive, almost mantra-like with gentle warnings of adding lean angle and throttle simultaneously. It would seem to me that removing lean angle and adding throttle as suggested by your "accelerating out of lean angle" statement would be just as perilous, as they are both done by a countersteering input.

 

 

That would be an incorrect assumption. What Cobie says about not adding throttle and lean on the same time is based on the fact that as lean angle is increased traction is decreased. There is more to it then that but that is the foundation of his statement.

 

As the bike stands up traction is increased so you can add much more throttle.

 

I think of it this way. The corner is split into three parts:

 

Turn in = off the throttle

 

Mid turn = throttle control, smooth roll on.

 

Drive = as hard on the gas as you can. The sooner you can get the bike picked up the sooner you can get hard on the gas. I'm coming into the throttle as hard as I think the rear tire will stand as soon as I start to stand the bike up, not after it is up.

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I noticed that lately Cobie has been a bit repetitive, almost mantra-like with gentle warnings of adding lean angle and throttle simultaneously. It would seem to me that removing lean angle and adding throttle as suggested by your "accelerating out of lean angle" statement would be just as perilous, as they are both done by a countersteering input.

 

 

That would be an incorrect assumption. What Cobie says about not adding throttle and lean on the same time is based on the fact that as lean angle is increased traction is decreased. There is more to it then that but that is the foundation of his statement.

 

As the bike stands up traction is increased so you can add much more throttle.

 

I think of it this way. The corner is split into three parts:

 

Turn in = off the throttle

 

Mid turn = throttle control, smooth roll on.

 

Drive = as hard on the gas as you can. The sooner you can get the bike picked up the sooner you can get hard on the gas. I'm coming into the throttle as hard as I think the rear tire will stand as soon as I start to stand the bike up, not after it is up.

 

I can see how the pickup drill would be helpful here.

 

Would all types of riders benefit from this type of technique? Only riders I see doing it in MotoGP is Edwards, I'm sure mainly due to his SBK roots. I haven't seen any 125 or 250 guys doing it, but then again I delete that stuff anyhow or watch it only when I'm pheenin'.

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I can see how the pickup drill would be helpful here.

 

I haven't seen any 125 or 250 guys doing it, but then again I delete that stuff anyhow or watch it only when I'm pheenin'.

First, if you're deleting the 250 racing, you're missing out on, not only future MotoGP champions, but GREAT racing. That and World Supersport are my favorites. WSBK is awesome to watch this year also.

I've heard it talked about, but don't know what the pickup drill is. Can you explain it?

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I can see how the pickup drill would be helpful here.

 

I haven't seen any 125 or 250 guys doing it, but then again I delete that stuff anyhow or watch it only when I'm pheenin'.

First, if you're deleting the 250 racing, you're missing out on, not only future MotoGP champions, but GREAT racing. That and World Supersport are my favorites. WSBK is awesome to watch this year also.

I've heard it talked about, but don't know what the pickup drill is. Can you explain it?

 

Pickup is a technique used for getting hard drives off corners that lead into a straight. It's covered in Level 2.

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I...don't know what the pickup drill is. Can you explain it?

It is the technique used when exiting certain corners where you push (countersteer) the bike up and away from you while you are still hanging off so you can add more throttle more quickly than you could at the lean angle you pushed the bike up from.

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I...don't know what the pickup drill is. Can you explain it?

It is the technique used when exiting certain corners where you push (countersteer) the bike up and away from you while you are still hanging off so you can add more throttle more quickly than you could at the lean angle you pushed the bike up from.

 

I found that I was able to push without countersteering. I'm not sure what would happen applying a steering input to bring the bike vertical.

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I...don't know what the pickup drill is. Can you explain it?

It is the technique used when exiting certain corners where you push (countersteer) the bike up and away from you while you are still hanging off so you can add more throttle more quickly than you could at the lean angle you pushed the bike up from.

 

I found that I was able to push without countersteering. I'm not sure what would happen applying a steering input to bring the bike vertical.

 

There seems to be a little bit of confusion on this subject! I believe the correct method for the pickup drill is to pull the inside bar while rolling on the throttle. pushing the outside bar would have a similar effect but you would be all out of shape stretched over the bike!

 

Jay, what exactly were you pushing without countersteering?

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I...don't know what the pickup drill is. Can you explain it?

It is the technique used when exiting certain corners where you push (countersteer) the bike up and away from you while you are still hanging off so you can add more throttle more quickly than you could at the lean angle you pushed the bike up from.

 

I found that I was able to push without countersteering. I'm not sure what would happen applying a steering input to bring the bike vertical.

 

There seems to be a little bit of confusion on this subject! I believe the correct method for the pickup drill is to pull the inside bar while rolling on the throttle. pushing the outside bar would have a similar effect but you would be all out of shape stretched over the bike!

 

Jay, what exactly were you pushing without countersteering?

 

Colin Edwards is an excellent example. I believe I've also seen Jason DiSalvo do it; in a hang-off position you'd push the bike away from you while maintaining your body's position relative to the ground. It looks retarded (esp. on the street), but it works well for getting the drive and keeping the bike on line.

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I...don't know what the pickup drill is. Can you explain it?

It is the technique used when exiting certain corners where you push (countersteer) the bike up and away from you while you are still hanging off so you can add more throttle more quickly than you could at the lean angle you pushed the bike up from.

 

I found that I was able to push without countersteering. I'm not sure what would happen applying a steering input to bring the bike vertical.

Ace;

I used the term push as if you are literally pushing the bike up and away from you and not meant to "push" on the outside bar. Whether you are "push/pulling" both bars or just "pulling on the inside bar" the result is that you are countersteering the bike to get it more verticle where you can add more throttle more quickly.

Sorry for the confusion.

Kevin

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I...don't know what the pickup drill is. Can you explain it?

It is the technique used when exiting certain corners where you push (countersteer) the bike up and away from you while you are still hanging off so you can add more throttle more quickly than you could at the lean angle you pushed the bike up from.

 

I found that I was able to push without countersteering. I'm not sure what would happen applying a steering input to bring the bike vertical.

 

There seems to be a little bit of confusion on this subject! I believe the correct method for the pickup drill is to pull the inside bar while rolling on the throttle. pushing the outside bar would have a similar effect but you would be all out of shape stretched over the bike!

 

Jay, what exactly were you pushing without countersteering?

 

Colin Edwards is an excellent example. I believe I've also seen Jason DiSalvo do it; in a hang-off position you'd push the bike away from you while maintaining your body's position relative to the ground. It looks retarded (esp. on the street), but it works well for getting the drive and keeping the bike on line.

 

when you watch top racers doing that, it does look like they are pushing the bike away from them but they are actually pulling the inside bar (c/steering) back to vertical while staying hung off the bike, it usually begins at or just after the apex and involves an impresive amount of wheelspin!

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