Keith Code

The 1G Club

26 posts in this topic

There are distinct phases riders must punch through on their route to improvement. All of them are based on personal battles waged against fear. For a newer rider even the simple sensations of leaning the bike over are strange.

 

Humans rely on the force of gravity as a constant. More than any other factor, things move and feel the way they do because of gravity. Every action of your body and your bike is measured and adjusted because of it. We ourselves gain intimate knowledge of gravity to maintain balance in our upright, stand, walk and run positions. This relies on a sensitive and detailed data acquisition system that we involuntarily obey to avoid the consequences--falling down.

 

Our most familiar orientation is perpendicular to the planet and all of our internal balance and visual machinery likes to keep it that way. Cornering motorcycles is diametrically opposed to those sensibilities.

 

The world begins to distort as we lean over. Once our visual orientation gets out of sync with the internal balance machinery it causes both the most rewarding and most terrifying sensations in riding. This is directly observable in new riders when they resist leaning by holding their bodies erect and press the bike down and away from themselves as they turn.

 

As riders become more accustomed to some lean angle they can go one of two ways (1) Continue as above to resist it or (2) Get sucked into the tantalizing sensations of cornering, often beyond their skill level. This too is easy to identify and generally is accompanied by scary turn-entry speed.

 

The barrier then is both physical sensation and visual orientation and I believe there is a make/break point in it. That point is 45 degrees of lean. At 45, the forces are a bit out of the ordinary. Along with the normal 1g down we now have a 1g lateral load as well. As a result the bike and our bodies experience an increase in weight. That’s not native to us and acts as a distraction and as a barrier.

 

Once we finally become comfortable with 45 and attempt to go beyond, the process begins to reverse. Immediately we have more lateral load than vertical load and things begin to heat up. Riders apparently have difficulty organizing this. Suddenly we are thrust into a sideways world where the forces escalate rapidly. While it takes 45 degrees to achieve 1g lateral, it takes only 15 degrees more to experience nearly double that, depending on rider position and tire size.

 

Paying your dues and joining the 1g club is the good stuff of riding. It opens up worlds of control, worlds of problems and worlds of rewards: putting your knee down at 45 is now very doable.

Up to 45 degrees riders can be pretty rough with the bike. Current suspension and tires will forgive. But once past that point it’s a brand new game. Just as we have to rewire our senses to deal with the new 45+ forces we must also adjust to using less force and more finesse.

 

Problems arise when we instinctually resist leaning with the bike. Speeds seem higher and, as the rider is out of alignment with the bike and the lateral g load, he must struggle to stay on the bike. Now the arms and body come into play, stiffening up. This tires us out from the physical tension which ultimately upsets the bike’s handling. Much like a counter-leaning passenger, it tends to stand the bike up and run it wide.

 

Awkward and uncomfortable body, neck and head positions result from this. Shoulders and hips twist away from, instead of into, the turn putting peculiar S curves in the rider’s back. This alone can upset the body’s orientation machinery.

 

About 15 years ago I developed an exercise called The Steering Drill. It looks very simple and can be done in a parking lot. The student simply rides away from the coach at about 25 mph and weaves the bike back and forth. That simple drill has 25 correction points. In other words, with low speeds and no panic, riders can make 25 different errors while weaving their bike back and forth. Each of those errors, while not deadly in a parking lot, can snowball into real problems out on the road.

All I want to do here is point out that there is something to every rider action, no matter how simple it may seem. Getting training is the only practical means riders have of breaking through their barriers.

 

© Keith Code 2013, all rights reserved.

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Good article. I am certain your discussion about angle and G-loading was derived from study of vehicles that travel in the 3 dimensional world (ie aviaion) and it makes the discussion here simplistiic for understanding.

 

I have observed riders tilting their heads to "normalize" the sensation of the inner-ear. Do you think this "remedial" behavior adversely affects rider perception?

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Good article. I am certain your discussion about angle and G-loading was derived from study of vehicles that travel in the 3 dimensional world (ie aviaion) and it makes the discussion here simplistiic for understanding.

 

 

Your views are common and incorrect!

There is nothing "simplistic" regarding the calculations of lean angle vs lateral G's.

An effective lean angle of 45 degrees ALWAYS yields to 1 lateral G. Period.

Effective angle = the angle between contact patch of tire and the Center of Mass. (can be slightly altered by rider position).

 

If you are at 45 degree lean and not doing 1 lateral G, you are not at equilibrium between centrifugal force and gravity meaning - you are a millisecond away from falling!

 

This direct relationship between effective lean angle and lateral G's seems to really piss off alot of riders. Most think that they and their bikes can defy the laws of physics, and that their recent $500 purchase of slicks is going to make them corner faster for a given lean angle.

False! A bridgestone Bt016 at 45 degrees will negotiate the exact same radius at 50mph as a racing slick. The only difference is:

The racing slick at 45 degrees is "yawning". Meaning - the tire is bored. It's only using lets say 30% of its potential allowing the rider to get on the gas hard at a lean. While the Bridgestone BT016 is probably working at 80% of its ability and excess throttle will overload the tire and the tire literally gives up.

 

And just to piss some of you guys some more. Your wheelbase, geometry, weight of your bike, height of the C.G. of your bike will NOT effect the fact that effective lean angle of 45 degrees will result in 1 lateral G. That means if a harley davidson could lean to 45 degrees, it would turn just as tight as your beloved zx6r or whatever you choose to ride.

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Good article. I am certain your discussion about angle and G-loading was derived from study of vehicles that travel in the 3 dimensional world (ie aviaion) and it makes the discussion here simplistiic for understanding.

 

 

Your views are common and incorrect!

There is nothing "simplistic" regarding the calculations of lean angle vs lateral G's.

An effective lean angle of 45 degrees ALWAYS yields to 1 lateral G. Period.

Effective angle = the angle between contact patch of tire and the Center of Mass. (can be slightly altered by rider position).

 

If you are at 45 degree lean and not doing 1 lateral G, you are not at equilibrium between centrifugal force and gravity meaning - you are a millisecond away from falling!

 

This direct relationship between effective lean angle and lateral G's seems to really piss off alot of riders. Most think that they and their bikes can defy the laws of physics, and that their recent $500 purchase of slicks is going to make them corner faster for a given lean angle.

False! A bridgestone Bt016 at 45 degrees will negotiate the exact same radius at 50mph as a racing slick. The only difference is:

The racing slick at 45 degrees is "yawning". Meaning - the tire is bored. It's only using lets say 30% of its potential allowing the rider to get on the gas hard at a lean. While the Bridgestone BT016 is probably working at 80% of its ability and excess throttle will overload the tire and the tire literally gives up.

 

And just to piss some of you guys some more. Your wheelbase, geometry, weight of your bike, height of the C.G. of your bike will NOT effect the fact that effective lean angle of 45 degrees will result in 1 lateral G. That means if a harley davidson could lean to 45 degrees, it would turn just as tight as your beloved zx6r or whatever you choose to ride.

 

Thank you for pointing out the error of my ways. When I said simplistic, I previously thought that simplistic was a grammatical change of the word simple and now after having defined the word from an online dictionary, I can see how it may be cause for confusion. It was not expected to start a flame of 1,000 posts. I have you to thank. Mucho Gracias, Senor.

 

With that said, I was really looking forward however, to your exegesis on how many are wrong on this subject of lateral acceleration? Please elaborate.

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And just to piss some of you guys some more. Your wheelbase, geometry, weight of your bike, height of the C.G. of your bike will NOT effect the fact that effective lean angle of 45 degrees will result in 1 lateral G. That means if a harley davidson could lean to 45 degrees, it would turn just as tight as your beloved zx6r or whatever you choose to ride.

 

So are you saying that if you have very wide tyres, a low CoG and a huge wheelbase it will corner exactly as fast as a short bike with narrow wheels and a high CoG, provided they are leaned over the same and the rider sits perfectly in line with the bike?

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And just to piss some of you guys some more. Your wheelbase, geometry, weight of your bike, height of the C.G. of your bike will NOT effect the fact that effective lean angle of 45 degrees will result in 1 lateral G. That means if a harley davidson could lean to 45 degrees, it would turn just as tight as your beloved zx6r or whatever you choose to ride.

 

So are you saying that if you have very wide tyres, a low CoG and a huge wheelbase it will corner exactly as fast as a short bike with narrow wheels and a high CoG, provided they are leaned over the same and the rider sits perfectly in line with the bike?

 

You must understand the difference between "effective lean angle" and "visual lean angle".

 

All single track vehicles regardless of wheelbase, CG height etc at 45 degrees will generate exactly 1G at a 45 effective lean angle.

Effective lean angle = the angle between the contact patch of the tire and the COG.

 

Visual lean angle is the angle of the bike itself relative to the horizon.

 

Due to tire width, effective lean angle will ALWAYS be less than visual lean angle since the contact patch is ALWAYS on the inside of the lean.

 

For example lets imagine a bike without a rider.

If the bike itself is leanning at 45 degrees (visual) with 10cm tire width, the "effective lean angle" will be something like 43 degrees.

If the bike had tire width of 50cm, the effective lean angle will be more like 35 degrees.

The higher the CG of the bike, the lesser the negative effect of the wider tire. Study the image below:

cg2.jpg

 

But visual lean angle (black line) is very meaningless. The angle that matters is the "effective lean angle".

So who would have thought? Your motorcycle with the 190's on the rear is actually less efficient at executing an aggressive lean angle as a bicycle with skinny tires.

 

Also note that visual lean angle vs effective lean angle are not worlds apart. Even on a very wide tire, the difference would not be that great since the reality is that motorcycle tires are never actually THAT wide.

 

So now that we only look at effective lean angle, i'll repeat. Every single track vehicle at 45 effective lean angle will corner 1G. Mr Code did not pull that number out of his ass trust me.

Lean angle and lateral G's are easily calculated using the Tangent function.

Lets do some math:

tan(0 degrees lean) = 0 lateral G's

Tan(10 degrees lean) = 0.176 lateral G's

Tan(30 degrees lean) = 0.577 lateral G's

Tan(45 degrees lean) = 1 lateral G's

Tan(60 degrees lean) = 1.73 Lateral G's

Tan(63.3 degrees lean) = 2 Lateral G's

 

The relationship between lean angle and lateral G's is not linear. That means you can't say something like "for every 10 degrees lean, we add another 0.176 G's).

Like Mr Code mentioned, once at 45 degrees lean, every little extra lean makes alot of difference regarding lateral G's.

 

So why all this talk about lateral G's? Why is it important? Because lateral G's symbolizes the relationship between a radius and a speed.

 

An example:

to negotiate a 200 foot radius turn if you travel at 55mph you will be pulling 1 lateral G. There is no way around that number. Whether you are running, driving in a car, or riding on a bike. 200 foot radius at 55mph will result in 1G of lateral acceleration.

That means exactly what it looks like. You MUST be at 45 degrees effective lean angle to ride on the 200 foot radius arc at 55mph. If you go faster, you will lean more and pull higher lateral G's.

 

It also means that if my bicycle tires had enough grip, that I would also be leaning to 45 degrees for this 200 foot radius turn at 55mph.

And if I was ice skating following a track of 200 foot radius at 55mph, i would lean to 45 degrees.

And my harley davidson if I raised the pipes and pegs and allowed it 45 degree lean, that's how much it would lean on the 200 foot radius at 55mph.

 

A single track vehicle is NOT a car, nomatter how much we want it to be. Lowering the CG, changing wheelbase will NOT effect the fact that 45 degree lean always results in 1 lateral G.

 

Changing wheelbase, C.G. etc will on the other hand effect handling characteristics. But alot of people misunderstand the term "handling".

Handling is NOT how hard the vehicle can turn (how many lateral G's it can execute).

A Formula 1 car can pull 3 lateral G's in a turn and handle like ###### and an old BMW can pull a max of 0.8 lateral G's and handle brilliantly.

Handling is about predictability. Ease of driveability. In the car world it would be something regarding understeer and oversteer. In the bike world it may be regarding how easily the bike flicks from side to side, or how stable it is under trail-braking. This predictability increases confidence. When a driver / rider is confident, they are more comfortable pushing the tires to their absolute limit.

 

I have a tutorial on my website that explains lean angles vs speed vs radius and various thought experiments i've came up with to attempt to explain the physics behind a single track vehicle - ie - motorcycle. Have a look and contact me on facebook if you would like any clarification I'm more than happy to explain...

http://www.howfastca...howitworks.html

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Noam, I knew this, I just got a little uncertain from your sentence That means if a harley davidson could lean to 45 degrees, it would turn just as tight as your beloved zx6r or whatever you choose to ride. I must say, though, that you managed to explain this topic very well in your last post!

 

If I'm not mistaken, tyre width will have the most impact at 45 degrees of lean and less the further you get away from that - be it more or less lean. At 0 and 90 degrees of lean, tyre width should have no impact whatsoever if my understanding is correct. Nor should CoG or wheelbase matter then.

 

Speed skating has become highly impressive where they go through a corner with a radius of 26 metres with a speed of about 16 metres per second - with just a thin steel edge to balance on. And they have to constantly put one foot in front of the other. That takes some leg power to withstand!

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If I'm not mistaken, tyre width will have the most impact at 45 degrees of lean and less the further you get away from that - be it more or less lean. At 0 and 90 degrees of lean, tyre width should have no impact whatsoever if my understanding is correct. Nor should CoG or wheelbase matter then.

 

 

Hey buddy. Glad you have the same brain as me and you are interested in this topic.

 

I don't really agree with your statement though. A wider tire will suffer a greater difference between "visual lean angle" vs "effective lean angle" at all angles. In fact, at moderate lean angles such as 20 degrees I think the thick tire would suffer a bit less since your contact patch is still towards the center of the tire. As you lean farther and farther you get to the edge of the tire which can create a big difference between visual and effective lean angle.

I drew up a picture of a bike leaning to 90 degrees visual lean.

Note that effective lean angle of 90 degrees can never be reached. You MUST have an infinitely thin bike and tires.

Something very magical happens as you get close to 90 degree effective lean angle. With "out of this world" tires you could get to lateral G's as high as you want as you approach 90 degree lateral G's approach infinity.

In other words, you could never lean the bike 90 degrees even if you had infinitely thin tires and blke because even when pulling 10,000G's the force of gravity will pull your bike down at 9.81m/s^2.

At 89 degrees lean angle you would need to execute a 57 lateral G turn and it would actually be possible if your tires can have that coefficient of friction and your body can withstand it hahaha

 

It is very sad that bikes and their physical dimensions only allow a 60 degree lean or so. Once you get past 60 degrees things can really get nasty - in a good way!

The difference between a 60 degree and a 70 degree lean is at 60 you do 1.7G's and at 70 you do 2.7G's!!! At 80 degrees you could do 5.6!!!! At that point we can corner better than a F1 car!!!

It's almost as if bikes have hit this barrier where they are not limited by grip of the tires. They are limited by physical dimensions and the amount of lean possible according to those dimensions. As better tire compounds advance through technology, we will never benefit in terms of mid-corner phase (mid corner speeds) but only in the aggressiveness of our trail braking / power out of the corner. Mid corner speeds are sort of set in stone, nomatter what we do with our tires.

 

A cool thing about a bike that is mentioned briefly in Code's article is it has built in "aero" in the turns... Most racecars need a fins to generate artificial gravity (downforce). The problem with fins is that anytime you create lift (down or up lift) you create drag which slows those cars on the straights.

On a bike when you turn the resulting force travels through the bike. In other words, the bike gets sucked into the ground the more you lean. Just like in geometry, when you do a 45 degree lean, like a 45 degree triangle, where the opposite, and adjacent are 1, makes the hypotenuse 1.4. At 45 degree lean, a bike and rider that weigh 600 pounds would put a force on the tire of 600*1.4 = 840 pounds! That's alot more grip!!!!!

 

90deg_zpscd942394.png

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Thank you for your explanation. My way of thinking was obviously wrong as I didn't consider the placement of CoG at 90 degrees, just that the tyres would both be "flat". My bad. Thanks for the corrections :)

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I assume you ignore the effects of wheelbase on turning radius by including it in the "effective lean" calculation

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No, wheelbase and effective lean angle have nothing to do with eachother.

Please explain to me the effects of wheelbase as it relates to turn radius, lean angle and speed. I would love to hear it...

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About 15 years ago I developed an exercise called The Steering Drill. It looks very simple and can be done in a parking lot. The student simply rides away from the coach at about 25 mph and weaves the bike back and forth. That simple drill has 25 correction points. In other words, with low speeds and no panic, riders can make 25 different errors while weaving their bike back and forth. Each of those errors, while not deadly in a parking lot, can snowball into real problems out on the road.

All I want to do here is point out that there is something to every rider action, no matter how simple it may seem. Getting training is the only practical means riders have of breaking through their barriers.

 

© Keith Code 2013, all rights reserved.

 

I wonder whether that 25 Correction Points is listed/mentioned somewhere? I did the Steering Drill during a 2-Day Camp - and I think several points to "fix."

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No, wheelbase and effective lean angle have nothing to do with eachother.

Please explain to me the effects of wheelbase as it relates to turn radius, lean angle and speed. I would love to hear it...

 

I believe that motorcycles actually have 2 contact patches, often times of differing size and not always inline with each other, and the distance between them does in fact make a difference on corner radius

An example:

to negotiate a 200 foot radius turn if you travel at 55mph you will be pulling 1 lateral G. There is no way around that number. Whether you are running, driving in a car, or riding on a bike. 200 foot radius at 55mph will result in 1G of lateral acceleration.

That means exactly what it looks like. You MUST be at 45 degrees effective lean angle to ride on the 200 foot radius arc at 55mph. If you go faster, you will lean more and pull higher lateral G's.

 

It also means that if my bicycle tires had enough grip, that I would also be leaning to 45 degrees for this 200 foot radius turn at 55mph.

And if I was ice skating following a track of 200 foot radius at 55mph, i would lean to 45 degrees.

And my harley davidson if I raised the pipes and pegs and allowed it 45 degree lean, that's how much it would lean on the 200 foot radius at 55mph.

 

so you mean that Paul Bunyan on his GSX13,000R with its stretched swing arm and 200 foot wheelbase will still complete a 200 foot radius turn at 1g and 55 mph ? and Stuart Little on his YZF-R0.006 with its 1 in wheelbase will make the same 200 foot radius at 1G and 55 mph ?

 

The Steering Angle section on this page http://en.wikipedia....orcycle_dynamic clearly shows the formula for calculating radius based on lean angle with regards to wheelbase

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I can see the confusion, and I'm not 100% sure I have the full grasp on this meself, but with wider tyres and longer wheelbase you need to lean further to achieve an actual 45 degrees. If you think how far the bike will have to lean, it will be more with a long and low bike than a tall and short one. But 1G is 1G regardless of the shape of the vehicle. As I understand it, at least.

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I don't disagree with the 45 degree 1 g correlation at all, it makes perfect sense in regards to gravity and balance, I simply disagree with the "Wheelbase has NO effect" part, I do believe you can account for wheelbase before the "Effective lean" angle, but to discount it entirely as irrelevant seems disingenuous.

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TireMockup_zps5828ac73.jpg

 

All the Tires/Bikes in this image at at 45° "Visual Lean", Tire dimensions are taken from Dunlops Website for 120/70-17 and 190/55-17 Q2's, the shorter wheelbase is 54.3" or that of a R6, the longer is double, Both Arcs are 25' Constant Radius

 

On the left I've placed all 4 contact patches on the line, but the Front tire of the Blue set is skewed out and wont maintain the radius at this lean angle, on the right I've left everything in line.

 

Please explain how wheelbase has no effect on Lean angle or Turning radius

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Please explain how wheelbase has no effect on Lean angle or Turning radius

 

OK, now you are getting picky but at least you are intelligent which I like!

In the common sense of wheel base effecting lean angle calculations where some people think that the Harley Davidson can't turn fast because its wheelbase is 69 inches and their zx6r can turn faster because if its shorter wheelbase of 55 inches that is not the deciding factor. The fact is that even if we take into account the wheel base into consideration, both bikes regardless of wheelbase would have the same effective lean angle for a given radius give or take 0.0001 degrees of lean.

 

What T-McKeen is talking about wheel base effecting lean angle is in fact true but negligible but still - I like that we are going this far into it.

 

Yes, if you look at the line created by the front tire versus the line created by the rear tire, the radius is different :)

The rear tire "trails" behind the front tire so the rear actually negotiates a smaller radius than the front.

 

If you've ever seen the difference between the 2 arcs created by front vs rear over a "normal" radius turn like we find at racetracks of over 200 feet radius, the difference between the front and rear is a matter of inches. Yes, inches in radius.

 

Now if for the same radius turn, we extend the wheelbase by an entire 2 feet, you would hardly notice a difference.

 

A wheelbase length will make noticeable difference in parking lot type turns where a long wheelbase bike's rear wheel will negotiate a significantly smaller radius turn.

 

So again: T-McKeen is correct. Wheel base will actually make a difference, but over a 200 foot radius turn, the difference between a 50 inch wheelbase bike and a 80 inch wheelbase bike would be so negligible, don't expect to be able to see it with the naked eye. Both bikes will look at identical lean angles.

 

In regards to calculations of wheelbase effecting lean angles, I think we would have to find out what radius the rear will negotiate. For example, if the front tire is turning 200 foot radius, the rear may be doing a 199 foot radius. Then I think we just average the two and get 199.5 and do the calculations for lean angle in regards to speed off of 199.5 foot radius.

 

I'll bust out some pen and paper and take a look at developing some formulas for this and get some hard figures. Sounds like fun!

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there is a world of difference from negligible effect and no effect, but I like where we are getting

 

After much thought and a lot of time staring at my 3D model I have a thought on your statement that everything at 55 mph and 1 G will cut a 200 ft radius, and it revolves around the "slip angle", the longer wheelbase bisects a larger portion of the radius its traversing , resulting in a greater "slip angle" which I would think means it needs more lateral acceleration to traverse the are then the shorter wheelbase, you can demonstrate this in the extreme with a wheelbase of double the radius where the wheels sit on opposing points along the circle and would have to actually "crab" sideways to traverse it, the opposite which would be a infinitesimally small wheel base would have almost no slip angle at all and need very little lateral acceleration to traverse the same arc.

 

Also every measurement I can manage shows the longer wheelbase naturally resulting in a lower "effective lean", which means the longer wheelbase in addition to needing slightly more G force to traverse the arc is also generating slightly less G force at a given angle

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there is a world of difference from negligible effect and no effect

 

Also every measurement I can manage shows the longer wheelbase naturally resulting in a lower "effective lean", which means the longer wheelbase in addition to needing slightly more G force to traverse the arc is also generating slightly less G force at a given angle

 

I stand corrected. Yes - wheelbase has effect period. nomatter how small of an effect.

 

So I think we both agree on the fact that the longer the wheelbase bike, the tighter radius the rear wheel will negotiate during a turn.

I drew this up real quick.

wheelbase_zpsa8e40f1b.png

Going CCW, black line is the front tire, blue line is the rear tire, and red lines represents the bike.

So lets say:

black line is 200 foot Radius

blue line is 190 foot radius

Shouldn't we just combine the 2 and get 195 foot radius?

 

That brings us to another question, when talking about radius of a turn, are we talking about the average between the two? Or the tightest one (rear)? or the radius the front tire tracks? Again, very negligeable especially when comparing to a car which you have the same problem. The outside of the car makes a considerably larger radius than the inside of the car. When I think of a car's turning radius, I think of the very middle of the car, The average between the inside tires and the outside tires.

 

Regardless, I think that the term "effective lean angle" needs some clarification then as you mentioned in your original post.

Effective lean angle should be the angle of the average of the 2 contact patches to the center of gravity of the bike. I have known this already not just because of the wheelbase argument, but more-so because the tire on the front is much thinner than the rear. But for the sake of forums and not confusing people that are following this thread and trying to understand, I think it's safe to say the following:

"Nomatter what type of bike or bicycle, or downslope skier, when you see the lean angle look like 45 degrees, they are pulling about 1G."

 

I can think of many other fun things to talk about in regards to physics of the bike. Too bad there is no specific forum for this.

One main thing I always wanted to find is how much exactly hanging off the bike really shift the COG.

Looking at photos I say the average good rider shifts their entire body around 1 foot towards the inside of the turn.

So if we have a 400Lbs bike, and a 200Lbs rider, since the rider weighs half as much of the bike, can't we then just say that the bike is leaning over another 6 inches? But of course we have to take into account the original COG of the bike alone without a rider. How do you measure that without having to balance the bike on a string? Just something to think about...

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At least one magazine back in the 70s used to show the actual CoG of the motorcycles they tested, so there must be a way to either measure this fairly easily or calculate it based upon a few measurements. Or perhaps they simply guessed :P

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At least one magazine back in the 70s used to show the actual CoG of the motorcycles they tested, so there must be a way to either measure this fairly easily or calculate it based upon a few measurements. Or perhaps they simply guessed :P

 

It's easy, you just put the bike on a pole and shift it around until it balances... :)

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Regardless, I think that the term "effective lean angle" needs some clarification then as you mentioned in your original post.

Effective lean angle should be the angle of the average of the 2 contact patches to the center of gravity of the bike. I have known this already not just because of the wheelbase argument, but more-so because the tire on the front is much thinner than the rear. But for the sake of forums and not confusing people that are following this thread and trying to understand, I think it's safe to say the following:

"Nomatter what type of bike or bicycle, or downslope skier, when you see the lean angle look like 45 degrees, they are pulling about 1G."

 

I think "Effective Lean Angle" works just fine for the 2D view of a single contact patch to CoG vs Visual Lean angle, What you need is a new term, I suggest "System Lean" which would be the combination of the "Effective Lean" of both tires, In regards to "System Lean" does weight distribution matter ?? if you are at a 60/40 weight load do you need to weight the average of your effective leans to properly calculate your system lean. How does the location of the CoG in the Z axis relate to the "effective lean" of each tire.

 

On a side note, in my experience anything that has a negligible effect on paper usually results in a small effect in practice, and a small effect on paper ends up a moderate effect etc. etc. for example on paper shifting around your weight on the seat only results in a few degrees of change, but in practice when I do it on a freeway interchange the effect is very noticeable

 

Tyler

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I was about to take Keith to task about his coaching only practical way to learn and then all you geniuses create lots of stuff I can't understand. Ha! I guess I'll have to try again sometime.

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I was about to take Keith to task about his coaching only practical way to learn and then all you geniuses create lots of stuff I can't understand. Ha! I guess I'll have to try again sometime.

 

OK, I tried again and its becoming slowly and painfully obvious. Thanks

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