# Cornering, tell me how



## early one (Jul 20, 2010)

Say you are riding quickly and go into a corner too fast. Will bad things happen if you lightly drag the brakes. Or should braking be kept on the straights.


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## Cableguy (Jun 6, 2010)

Ideally you want to identify that you're going into a corner too fast as soon as possible, so you may have time to straighten out the bike for a moment, break hard, then resume leaning the bike. If you don't have the luxury of straightening out the bike (i.e. it's too late or there are people surrounding you) then you can lightly apply the *front* brake. I'm not sure if its ever a good idea to apply the rear brake while leaning, but if you do it should be done very cautiously.


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## Local Hero (Jul 8, 2010)

Keep it on the straights if you can. Your tires only have so much grip. 

That grip can go to braking, cornering, or divided between the two. When you're in a high-g turn and much of the grip is going to cornering, adding the force of braking will increase the likelihood of washing out.


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## charlox5 (Jan 31, 2011)

if there's no room to reduce lean angle and i'm committed, i would look through the turn, lean into the turn, and hold my line. 

braking mid-corner (front or rear) at the limits of traction is a bad idea. Though people often underestimate the amount of grip a bicycle tire has--using the available grip for fear-based braking is usually a bad idea, since people tend to lack finesse on the brakes when they're about to **** their pants. 

As for which brake to use midcorner, too much front brake will wash out the front, too much rear brake may wash out the rear or highside you. That being said, high level motorcycle racers sometimes use the rear brake (VERY LIGHTLY) mid corner to settle the back end--but that's probably more to do with a motorcycle's suspension than it is the bike's handling dynamics. 

Going into corners too hot and committing is often how we re-establish our limits and our comfort zones, however.


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## early one (Jul 20, 2010)

I agree that the tires only have so much grip. Does using the brakes to slow the wheel change the centrifugal force on the wheel making the bike straighten up when you need it to lean into the turn.


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## charlox5 (Jan 31, 2011)

early one said:


> I agree that the tires only have so much grip. Does using the brakes to slow the wheel change the centrifugal force on the wheel making the bike straighten up when you need it to lean into the turn.


yes, getting on the brakes will either stand the bike up, provided there is enough grip to do so or wash out the wheel.


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## kbiker3111 (Nov 7, 2006)

I don't know what everyone else is talking about but I regularly lightly trail brake through a turn, often in crits. No problem if you do it correctly.

Further if I remember my slip angles correctly, the front wheel has more forces on it than the rear (although this may just be the 4 wheeled world), so logic would indicate the rear brake should be biased more than the front.


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## AJL (Jul 9, 2009)

kbiker3111 said:


> I don't know what everyone else is talking about but I regularly lightly trail brake through a turn, often in crits. No problem if you do it correctly.
> 
> Further if I remember my slip angles correctly, the front wheel has more forces on it than the rear (although this may just be the 4 wheeled world), so logic would indicate the rear brake should be biased more than the front.


I do the same when flying downhill (though I don't compete), except when I see sand or gravel. I always brake the rear tire b/4 the front (learned that lesson painfully on a dirt bike). Four wheeled vehicles have differentials in them and that changes everything.

--------—----------—---------—-------—----------—----------—---------—---

As far as how far you can really lean, you don't like know unless you've bounced a pedal off the road when pedaling through a turn (try it if you are an adrenaline junkie).

The total force on the rear tire will be greatest in almost all situations (notice how close your saddle is to the rear tire vs. the front), so the rear tire is providing the highest amount of 'grip'. What can be done with that grip depends on the contact patch geometry, which varies with tire width, tire pressure and rider weight. So, really, you need to know your own bike.

The worst thing you can do is panic, which typically results in said panicked rider: a) braking too hard which results in an endo or washout b) letting the bike stand up, which will send you into the woods, or worse. c) trying to lean the bike over too hard, which will washout or send you into a ditch, or worse.

If you have problems with this and can't seem to master it, go for a wider tire which will give you more lateral grip.


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## new2rd (Aug 8, 2010)

How about technique with weight distribution (inside leg up at 12 o'clock, more weight on outside straight leg, bike leaned more than rider, etc..) I'm of the nervous variety of riders when it comes to cornering especially downhill, any technique help would probably be useful in this thread. I've heard people mention weight distribution a bit, but I'm not sure what I should try.


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## charlox5 (Jan 31, 2011)

new2rd said:


> How about technique with weight distribution (inside leg up at 12 o'clock, more weight on outside straight leg, bike leaned more than rider, etc..) I'm of the nervous variety of riders when it comes to cornering especially downhill, any technique help would probably be useful in this thread. I've heard people mention weight distribution a bit, but I'm not sure what I should try.


inside pedal up creates more ground clearance to prevent a pedal strike mid corner, but leaning the bike more than your body is counter to what I perceive as the correct way to corner. Shifting your body weight to the inside of the turn, will allow you to make a tighter radius turn using less lean angle. doing the opposite has the opposite effect. this is based off my experience riding motorcycles, which is where you see guys "hanging off like spider monkeys" into the inside of the turn. conversely, dirt bike riders/supermoto riders will weight the outside peg, keep their bodies upright, but the are also generally using the inside leg to counterweight or change the weight distribution, and this generally means taking your foot off the peg. since most of us are clipped in, this doesn't seem practical.


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## new2rd (Aug 8, 2010)

charlox5 said:


> inside pedal up creates more ground clearance to prevent a pedal strike mid corner, but leaning the bike more than your body is counter to what I perceive as the correct way to corner. Shifting your body weight to the inside of the turn, will allow you to make a tighter radius turn using less lean angle. doing the opposite has the opposite effect. this is based off my experience riding motorcycles, which is where you see guys "hanging off like spider monkeys" into the inside of the turn. conversely, dirt bike riders/supermoto riders will weight the outside peg, keep their bodies upright, but the are also generally using the inside leg to counterweight or change the weight distribution, and this generally means taking your foot off the peg. since most of us are clipped in, this doesn't seem practical.


I rode motorcycles for a while, but the tires have a wider contact and theres a good amount of weight centered low on the frame. For that reason I've been too chicken to just lean into a turn that way especially going downhill if I see anything resembling loose chipseal or gravel.


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## charlox5 (Jan 31, 2011)

it's difficult for me to get a "cheek of the seat" and kiss the mirrors on a road bike, but i will usually lean into a turn using my upper body, open my chest up to the apex of the turn, and look through the corner. I don't think we'll see 48 degree lean angles from road bike descents, but i think the physics are still analogous.


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## Creakyknees (Sep 21, 2003)

Wow, so much misinformation in this thread.

1) given a clean dry surface, standard road tires have amazing levels of grip. E.g. they will handle a much steeper turn than any of us are comfortable with. 
1a) but, safety and caution and real-world life is that there's always going to be a layer of dust or sand or whatever. So be careful.

2) proper technique counts for a LOT. 
2a) hands on the drops > more weight on the front contact patch (better grip)
2b) outside pedal weighted > lower effective CG, better ability to absorb bumps
2c) most riders are terrible at choosing the right line through a fast turn. By far, they all start turning in way too early, apexing too soon, exiting too slowly. This leads to a lot of panic braking.
2d) as noted, brake before the turn; if I'm descending, for example, I'll brake hard in a straight or nearly straight line, up til it's time to "dive into" the turn, at which point I release the brakes, which aids the quick "dive" without hampering traction.
2d1) however in the right hands, braking can actually increase traction

Traction (engineering) - Wikipedia, the free encyclopedia


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## charlox5 (Jan 31, 2011)

Creakyknees said:


> 2d1) however in the right hands, braking can actually increase traction
> 
> Traction (engineering) - Wikipedia, the free encyclopedia


I think it's worth mentioning that there are two things happening when braking at turn in: 1) loading the front wheel through front rear weight transfer, 2) percentage of grip required for turning and braking. So yes, loading the front wheel by braking will increase grip by loading the front wheel, but at some point, the amount of grip required to brake and turn will overcome available grip leading to loss of traction.


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## aclinjury (Sep 12, 2011)

First, let's talk about the basic cornering techniques. Outside foot firmly planted down, arms, especially the inside arm, are pushing down on the handlebar. Let me just say this right now. A user above said that most people underestimate the grip due to fear of crashing. This is true. Assuming that you have good rubber and the pavement is dry and clean, then you should be feeling like you're doing push-ups on your arms, and you are working hard to keep your neck looking straight... it's at this point that you will approach grip limitations. Many people, especially newbies or recreational riders, will never get even close to this limits before they will start to tap their brakes. In other words, many people still have quite a bit of room left for grip. Problem here where does this grip limitation, and unfortunately the only way to find out is to approach it until you start to feel the tire slipping. On a motorcycle, you can actually feel this, and still have some room left to take correctional courses. Unfortunately, on a road bicycle, the fall off cliff is sudden and dramatic, it is usually an all-or-nothing event, you either make the corner or you crash out. However, it's only crashing out that you will learn.

But there are warning signals before a front tire will give. You will definitely hear it push against the pavement. oh yes you will. And you will feel like you're doing pushup on your arms. Your neck will be pushed down by the g-force.

Now back to braking. Assuming that you have used up most of your grip in corner, then the next step is trail-braking. This is really an advanced technique that should only be used as an aggressive take-over move. Yet, I see too many guys using this technique even BEFORE they get close to grip limitations (I know this judging by their speed and mine). If you must trail brake, you should at least slow down enough so that by the time you hit the apex of a corner, you're already off the brake. If you divebomb into a corner and overcook it, and you're expecting to use your brake to "save" you,, well good luck with that, and please stay away from me on the road. But if you do trail brake, then you want to make sure you don't upset the bike especially as it is transitioning from straight to leant over position. Brake hard as the bike is straight, and slow ease off the brake as you round the corner. It will take a tons of practice to get the feeling right.

My advice is to do all your braking in a straightline, it's probably better to do late-braking in a straightline then to trail-brake in a corner, especially with a bunch of weekend warriors who might not be on the same mindset as you. But late braking can rob you of speed so it also has its drawback too. In professional motorcycle racing, all the pros think and act the same in a corner, so everyone is synchronous (but even there there will be some knucklehead overcooking his line wipe out and taking somebody with him). In amateur bicycle racing, it's trial-n-error at its finest.

Regarding using a wider tire for better grip. This is not always the case. First of all, if you're trail braking into a corner, then the contact patch will transition from the center of the tire to the SIDE of the tire as the bike is lean over. A wider tire with a shallow sidewall (see those motorcycle "chopper" tire) will not give you as much grip as a narrower tire with a higher sidewall. Racing motorcycle tires have a higher sidewall exactly for this purpose. Cruiser & chopper run wide-ass tires with relatively shallower sidewalls, won't help at all. Same concept applies to bicycle tire. The difference between a 23c and 25c tire under braking in a corner is probably zero if their sidewall height is pretty much the same. Let me give an example, I know a buddy who is really a demon on the descent, this guy would keep up with many noobie motorcyclists (obviously not with the kneedragger type) down a 10 mile descent with an average 6-7% gradient. He's on 23c tires. He would take a corner at 35-40 mph when I'm only doing 25 mph (I could push it to 30 mph but that would put me out of my comfort zone). Motorcycle guys (the amateur ones) are doing around 40 mph on the same corner. I'm always amazed at his control around a corner. Theoretically, I realize that I still have plenty more grip under me (because I'm going 25 mph and he's going almost 40 mph), yet I'm always fearful of committing at higher speed, so I just don't. Takes lots of practice, and guts, to be like my buddy (he also has his fair share of wipeouts before he can be this good).


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## Local Hero (Jul 8, 2010)

It's not difficult to descend faster than motorcycles and cars if the curves are right. 



kbiker3111 said:


> I don't know what everyone else is talking about but I regularly lightly trail brake through a turn, often in crits. No problem if you do it correctly.


Of course. But are you scrubbing off speed to avoid the guy in front of you or to avoid washing out? 

It's a mistake to think that braking during a turn is going to improve traction unless there's a decreasing-radius.


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## kbiker3111 (Nov 7, 2006)

Local Hero said:


> It's not difficult to descend faster than motorcycles and cars if the curves are right.
> 
> 
> Of course. But are you scrubbing off speed to avoid the guy in front of you or to avoid washing out?
> ...


Scrubbing off speed before the apex to avoid washing out. No one is in front of me in a race. Ever.


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## ToffieBoi (May 1, 2011)

View attachment 274380


I think this photo is a good example for cornering. How you should stand on the bike.
About braking, it is all about the limits of your bike and tires. Time by time, when you got used to your equipment, you will understand your bikes limits and it will be easier to corner. You can use the brakes, rear and front both as long as you know where bike will wash out.


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## Creakyknees (Sep 21, 2003)

charlox5 said:


> I think it's worth mentioning that there are two things happening when braking at turn in: 1) loading the front wheel through front rear weight transfer, 2) percentage of grip required for turning and braking. So yes, loading the front wheel by braking will increase grip by loading the front wheel


yup, but use with caution



charlox5 said:


> but at some point, the amount of grip required to brake and turn will overcome available grip leading to loss of traction.


Not always - it is pretty easy to nose-wheelie or (it's turning equivalent) high-side without skidding the front tire, if you apply front brake too aggressively on clean surface. 

Which leads to another cornering tip, since this is a tips thread: 
- practice
- on various surfaces and slopes
- on different bikes - e.g. an mtb clinic will really help. Or cx'ing is fantastic for skillz.


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## kbiker3111 (Nov 7, 2006)

This thread just reminds me how important it is for people to occasionally go mountain biking or at least cxing so they understand how the bike behaves at the limits of adhesion. 

[just went out on the snowy trails!!!]


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## danl1 (Jul 23, 2005)

Creakyknees said:


> Wow, so much misinformation in this thread.
> 
> 1) given a clean dry surface, standard road tires have amazing levels of grip. E.g. they will handle a much steeper turn than any of us are comfortable with.
> 1a) but, safety and caution and real-world life is that there's always going to be a layer of dust or sand or whatever. So be careful.
> ...


2b) is false. unless the body moves downward, the CG doesn't change. "weighting the outside pedal" to lower CG is a persistent myth. However, that tends to get the weight off the saddle, and move the body slightly to the inside. That keeps the bike itself slightly more upright, which aids steering geometry, and provides a bit of margin. If the bike hits small bumps or loses a bit of traction, the wheels can move out (flattening the bike sligthly) without fundamentally screwing the dynamics of the turn and washing out. So, right advice, wrong reason.

2D is dangerously false. A tire has only so much traction, and it can be used to help shove the bike around the corner, or it can be used to slow the bike - and those are different vectors in a turn. Traction 'spent' on braking will decrease the amount available to change direction.

There is no reason to brake in a single-apex turn (traffic notwithstanding). If you are able to brake during a turn, you could have made it through without braking. There can be exceptions to that for decreasing-radius bends or turns that increase slope midway through.


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## Creakyknees (Sep 21, 2003)

danl1 said:


> 2D is dangerously false. A tire has only so much traction


What happens to the weight on the front tire when you brake?


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## AJL (Jul 9, 2009)

Creakyknees said:


> What happens to the weight on the front tire when you brake?


Since human beings are not rigid bodies, we move forward and load the front tire move heavily. This is especially true when one is off the saddle and on the pedals (greater freedom of movement).

I think the reason I tend to take corners fast is, like Aclinjury's friend, I'm enough of an adrenaline junkie that I've pushed too hard and washed out a couple of time (plus one endo). I probably trail brake because I've found I get better traction (probably because I'm moving some of the load from the rear to the front tire) and I'm able to get a better sense of when I'm reaching my cornering limit, and can give myself a little bit more headroom by laying off the brake (something that I like in Michelin tires, both for my car and bike).


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## Creakyknees (Sep 21, 2003)

So, how do you reconcile these two statements?



danl1 said:


> ...2D is dangerously false. A tire has only so much traction, and it can be used to help shove the bike around the corner, or it can be used to slow the bike - and those are different vectors in a turn. Traction 'spent' on braking will decrease the amount available to change direction.





AJL said:


> Since human beings are not rigid bodies, we move forward and load the front tire move heavily. This is especially true when one is off the saddle and on the pedals (greater freedom of movement).
> 
> ...I probably trail brake because I've found I get better traction (probably because I'm moving some of the load from the rear to the front tire)


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## Local Hero (Jul 8, 2010)

Cornering on a motorcycle is different. 

The torque going to the rear wheel creates additional forces.


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## foto (Feb 7, 2005)

Creakyknees said:


> So, how do you reconcile these two statements?


AJL is incorrect.


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## foto (Feb 7, 2005)

foto said:


> AJL is incorrect.


Braking in a turn is always wrong. Unless you want to drift the turn, then it's always right.


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## charlox5 (Jan 31, 2011)

Creakyknees said:


> So, how do you reconcile these two statements?


they're both right.

as load increases over the front tire, normal force is increased, and so is frictional force. However, at some point the two force vectors (braking and turning) will overcome the increase in frictional force and break the tire loose. this also doesn't take into account any road regularities and tire deflection or shock absorption. This is over a very regular, theoretical surface. 



Local Hero said:


> Cornering on a motorcycle is different.
> 
> The torque going to the rear wheel creates additional forces.


Only at track out/corner exit. At corner entry and mid corner, the motorcycle is going to handle very similarly to the bicycle, since you don't want to be on the throttle before corner apex. And generally, going into a corner too hot means that you are dealing with the effects at turn in or mid corner.


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## AJL (Jul 9, 2009)

foto said:


> AJL is incorrect.





foto said:


> Braking in a turn is always wrong. Unless you want to drift the turn, then it's always right.


You must be looking at this statically instead of dynamically to be thinking this way. That, or I need to tell my University to revoke my BS in Physics.
If I rode the same mileage as Pros do, I would do fine without trail braking. But @ 1500mi/year I don't have the experience to bomb corners without giving myself some safety edge. Again, bombing downhill turns at 30+ mph, my Michelin Krylions let me know when I'm pushing them too hard. The are a very predictable tire. When this happens I back off the brake and I'm good to go (I can maintain the same lean angle and position using upper body strength to keep my self more forward). There are downhill turns that have been part of many of my routes (which often have the same beginning leg) and I take those without any braking, because I have learned, by feel, that I can take them at a consistent speed without compromising my safety. So if one is a Pro, or has learned how to take certain corners over the course of time - then you are right, one can take them at a fast and stable speed every time w/o touching ones brakes. Perhaps this is what you were getting at.

In my experience, it is not the best way to take downhill turns that I am unfamiliar with. Perhaps it's just 'my style', but the basic physics works out as well.


FWIW - Shouldn't this topic be moved to another forum?? I just realized that it's in Pro Cycling.


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## foto (Feb 7, 2005)

charlox5 said:


> they're both right.
> 
> as load increases over the front tire, normal force is increased, and so is frictional force. However, at some point the two force vectors (braking and turning) will overcome the increase in frictional force and break the tire loose. this also doesn't take into account any road regularities and tire deflection or shock absorption. This is over a very regular, theoretical surface.
> 
> ...


The weighting of the front wheel is not a factor in how fast you can take a turn before losing traction. Because friction force is proportional to mass, the mass of the system drops out in determining maximum cornering speed.


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## foto (Feb 7, 2005)

Well, ok. So you drag a brake in turns to maintain a margin. I prefer to not too, and lean the bike over further. That's a personal style thing.

however, you are reducing your lateral traction by using your brake in the turn...



AJL said:


> You must be looking at this statically instead of dynamically to be thinking this way. That, or I need to tell my University to revoke my BS in Physics.
> If I rode the same mileage as Pros do, I would do fine without trail braking. But @ 1500mi/year I don't have the experience to bomb corners without giving myself some safety edge. Again, bombing downhill turns at 30+ mph, my Michelin Krylions let me know when I'm pushing them too hard. The are a very predictable tire. When this happens I back off the brake and I'm good to go (I can maintain the same lean angle and position using upper body strength to keep my self more forward). There are downhill turns that have been part of many of my routes (which often have the same beginning leg) and I take those without any braking, because I have learned, by feel, that I can take them at a consistent speed without compromising my safety. So if one is a Pro, or has learned how to take certain corners over the course of time - then you are right, one can take them at a fast and stable speed every time w/o touching ones brakes. Perhaps this is what you were getting at.
> 
> In my experience, it is not the best way to take downhill turns that I am unfamiliar with. Perhaps it's just 'my style', but the basic physics works out as well.
> ...


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## aclinjury (Sep 12, 2011)

This is how the top pros descend

Evans' and Gilbert's Epic Descent - YouTube

Cadel Evans and Gilbert are demon on the down. 50 mph around those sweepers is simply jaw dropping. They left the peloton in the dust.


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## aclinjury (Sep 12, 2011)

foto said:


> *The weighting of the front wheel is not a factor in how fast you can take a turn before losing traction.* Because friction force is proportional to mass, the mass of the system drops out in determining maximum cornering speed.


Weighing the front wheel has the effect of putting more weight into it, and this means it changes the contact patch and therefore frictional force being applied into it, and therefore affects the speed of how fast you can take a turn (since affecting friction also affects grips which affect how fast you can take a turn. It's the front that turns).

Examples:

1) in for Formula 1, if a car loses its front wings, it loses front end downforce and therefore loses most of its turning ability

2) in motorcycle, if the rider is heavily trail-braking (loading the front-end) around a turn, and now if he suddenly releases the front brake (unload the front-end), the front tire will slide out.

If you don't think weighing the front matters, then try to get way off the back of the saddle (ala mountain biking) next time you're banking a corner at say 30 mph mph, and see if your front will track thru the corner or washout on you.

In fact, in your second statement, you even said frictional force is proportional to mass (f = ma). Therefore, if we change the weigh (by weighing down the front), then we also cause a change in frictional force.

I think what you meant to say is that the *overall* frictional force of the system is not changes, this is true. However, when we weigh the front end, we sacrifice the rear end frictional force (ie, front frictional force increases, rear frictional force decreases). Overall frictional force of the system is still conserved.

On a bicycle, it's the front end that determines where the bicycle will go.


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## Local Hero (Jul 8, 2010)

charlox5 said:


> Only at track out/corner exit. At corner entry and mid corner, the motorcycle is going to handle very similarly to the bicycle, since you don't want to be on the throttle before corner apex.


Many things are similar between motorcycles and bicycles. Some things are different. 

When you are cornering on a bicycle you are not putting down the power. 

Motogp racers keep their bikes in gear throughout the turn. 
2011 Laguna Seca MotoGP Action from the Corkscrew - YouTube
They are not freewheeling down the corckscrew. 

Check this out: Catalunya 2009 Motogp 'Rossi teaches Lorenzo a lesson!' on Vimeo Listen to the bikes. The power is on during the turns. 


The throttle is engaged. The torque going to the rear wheel allows the bike to lean like that. Let off the throttle and the bike stands up. Or it will even high-side. This guy begins to slide out and lets off the throttle, only to high-side: High Side - YouTube


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## foto (Feb 7, 2005)

aclinjury said:


> Weighing the front wheel has the effect of putting more weight into it, and this means it changes the force being applied into it (since f = ma), which affects friction (since friction is also a force) and therefore affects the speed of how fast you can take a turn (since affecting friction also affects how fast you can take a turn).
> 
> Examples:
> 
> ...


If you consider just the radial components of force than newton's second law is really simple...

f=ma

f-friction = mu*m*g

mu*m*g = ma

mu*g = a

Mass independent. Work it out for yourself.

As for riding a turn like a mountain bike on a descent, that wouldn't work because you are riding your bike like a goon, and bikes don't work well when ridden by goons.

This is like week 2 of physics 101.


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## aclinjury (Sep 12, 2011)

It's not mostly torque that enables motocycle to lean at insanely like that. 

First and foremost is tire technology. Period. Racing motocycle rubber feel like bubble gum. They're sticky.

Then you have the engine help holding the motorcycle at a constant speed during a turn (not the case of a human powered bicycle, we can't pedal during a turn much). Ability to hold a constant speed and not upsetting the bike is more important than torque.

Furthermore, back in the 2-stroke era, these 2stroker engines behaved like on/off switch. When it was on (high rpm), it was generating lots of power and lots of torque, but when it was off (low rpm), it created basically no power and barely any torque. Those who tried to put the power down early during a mid-turn (I'm only talking about slightly opening up the throttle), they were greeted with a highside. Yet those 2-stoke racer were dragging and sliding their knees like mad around corner, their corner speed was almost every bit as fast as a modern racing motorcycle.

What a constant and controllable torque to the rear wheel (in the 4-stroke era) does is enable more stability, but it not the main component to why a modern racing motorcycle is able to be lean at extreme angle. The main contributing factor here is the improvement in tire technology. The saying in motorcyle racing is that you can only go as fast as the tires allow you to, and in fact, the sanctioning body tries to control the speed of these machines by control limiting tire choices for the racers.


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## aclinjury (Sep 12, 2011)

foto said:


> If you consider just the radial components of force than newton's second law is really simple...
> 
> f=ma
> 
> ...


You are talking about the whole system. However, changes can happen within a system as long as the total forces (from the front and rear end) of the system is conserved. No?

Your goon example is cute... but you're only showing that you don't understand conservation of forces within a system. Please ask your Physics 101 prof about the law of conservation of energy


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## foto (Feb 7, 2005)

aclinjury said:


> You are talking about the whole system. However, changes can happen within a system as long as the total forces (from the front and rear end) of the system is conserved. No?


You can deal with both wheels separately or together, Newton's second law doesn't really care.



> Your goon example is cute... but you're only showing that you don't understand conservation of forces within a system. Please ask your Physics 101 prof about the law of conservation of energy


I have never heard of conservation of forces, so that is a new one for me.

Anyway, what law of conservation of energy should I familiarize myself with? Are you talking about the 1st law of thermodynamics? I am not in school so maybe you should explain it, since it's your claim...


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## Local Hero (Jul 8, 2010)

aclinjury said:


> Ability to hold a constant speed and not upsetting the bike is more important than torque.


What exactly is it that gives motorcycles the ability to hold constant speed through turns? 

What happens when the throttle is released during a turn? Why do bikes high-side?

Where does torque come from?


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## aclinjury (Sep 12, 2011)

foto said:


> You can deal with both wheels separately or together, Newton's second law doesn't really care.
> 
> 
> 
> ...


It is not my claim. Just because you're not aware of such law does not make it my claim. A 5 second googling on such law will take you to plenty of wiki and university sites explaining it in much more detail then I ever could. And there is only one law of conservation of energy. So go apply yourself man rather than play dumb with me. Surely for a person who is familiar with f=ma and Physics 101,... you're not dumb, right!


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## Local Hero (Jul 8, 2010)

aclinjury said:


> It is not my claim. Just because you're not aware of such law does not make it my claim. A 5 second googling on such law will take you to plenty of wiki and university sites explaining it in much more detail then I ever could. And there is only one law of conservation of energy. So go apply yourself man rather than play dumb with me.


^a white flag


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## aclinjury (Sep 12, 2011)

Local Hero said:


> ^a white flag


nah, I don't play dummy pissing game. Go apply yourself.


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## rider9 (May 27, 2011)

Putting the outside foot down does not change the CG as already stated above, but it does increase the force applied to the road surface, giving you a better "grip" on the pavement. Braking through a turn is not a good idea. Braking before a turn is the best way.


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## Local Hero (Jul 8, 2010)

aclinjury said:


> nah, I don't play dummy pissing game. Go apply yourself.


Are you going to ignore post #39? 

I think that when you consider the questions I asked--without being argumentative for the sake of argument--you will see the difficulty in your position. 

Think about why a motorcycle stands up or high-sides when the power is let off. It doesn't have much to do with the sticky tires.


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## foto (Feb 7, 2005)

aclinjury said:


> It is not my claim. Just because you're not aware of such law does not make it my claim. A 5 second googling on such law will take you to plenty of wiki and university sites explaining it in much more detail then I ever could. And there is only one law of conservation of energy. So go apply yourself man rather than play dumb with me. Surely for a person who is familiar with f=ma and Physics 101,... you're not dumb, right!


Done.

Conservation of force - Hmolpedia



> In thermodynamics, the conservation of force or "law of conservation of force" is a view, promoted largely by German physicist Hermann Helmholtz, beginning in 1847, which argues that the quantity of force in the universe, called “kraft”, is conserved. [1] The logic of the theory was later re-incorporated into the more robust law of conservation of energy and then into the first law of thermodynamics, by German physicist Rudolf Clausius.


hmm...enlightening.

Maybe I'm dumb, but I don't get what this has to do with cornering of bicycles or motorcycles.


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## foto (Feb 7, 2005)

aclinjury said:


> nah, I don't play dummy pissing game. Go apply yourself.


You failed to provide a convincing position, other than to tell others to go do their homework. Your surrender is understandable and appreciated.


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## aclinjury (Sep 12, 2011)

Local Hero said:


> What exactly is it that gives motorcycles the ability to hold constant speed through turns?
> 
> What happens when the throttle is released during a turn? Why do bikes high-side?
> 
> Where does torque come from?


I think you go watch lots of those 125cc 2-stoker racing. It'll answer much of your questions.


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## aclinjury (Sep 12, 2011)

foto said:


> Done.
> 
> Conservation of force - Hmolpedia
> 
> ...


corning on a bicycle or motorcycle (or on a Nascar or F1 cars for that matter) deal with forces, and ultimately engergy. All these notions such as mass, force, friction, acceleration, momentum, engery, and all of their derivatives, etc.. are all governed by the law of energy conservation. You were referring to a system wide conservation, and I did said you were right. But you fail to see that system wide conservation does not mean there can't be any variation within a system itself (which is what I'm referring to).


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## aclinjury (Sep 12, 2011)

foto said:


> You failed to provide a convincing position, other than to tell others to go do their homework. Your surrender is understandable and appreciated.



Sorry not to sound like a prick, but where I come from, if someone tell you that you are wrong, and that that the information is out there easily researched, then it's your job to take the initiative. I'd be embarrassed to ask other to spoon feed me the info. You posted the f = ma stuff, you mentioned Physics 101.. I assume you also have the capacity to look around for an easily attainable answer. Furthermore, these sites from wiki and the universities can explain in much greater detail than I can over the webz. So why should I take the time to try to repeat what has already been elegantly explained? when all it takes is 30 seconds of googling some initiative from you? which you ultimately did anyway!


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## foto (Feb 7, 2005)

aclinjury said:


> corning on a bicycle or motorcycle (or on a Nascar or F1 cars for that matter) deal with forces, and ultimately engergy. All these notions such as mass, force, friction, acceleration, momentum, engery, etc.. are all govern by the law of energy conservation. You were referring to a system wide conservation, and I did said you were right. But you fail to see that system wide conservation does not mean there can't be any variation within a system itself (which is what I'm referring to).


You clearly are either incapable or unwilling to explain the physics. I am going to go with "incapable" until you convince me otherwise.


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## foto (Feb 7, 2005)

aclinjury said:


> Sorry not to sound like a prick, but where I come from, if someone tell you that you are wrong, and that that the information is out there easily researched, then it's your job to take the initiative. I'd be embarrassed to ask other to spoon feed me the info. You posted the f = ma stuff, you mentioned Physics 101.. I assume you also have the capacity to look around for an easily attainable answer. Furthermore, these sites from wiki and the universities can explain in much greater detail than I can over the webz. So why should I take the time to try to repeat what has already been elegantly explained? when all it takes is 30 seconds of googling some initiative from you? which you ultimately did anyway!


You mean like this?

https://www.google.com/search?q=cor...e.1.57j0l2j62l3.4691&sourceid=chrome&ie=UTF-8

Let's take a look at the third result:

Turn Radius, Speed, Lean Angle



> Side Force Equals Friction
> 
> Now to put our two equations together: For a car traveling at a speed v around a turn of radius r, the side force is mv2/r; and the frictional force available to prevent sliding is μmg. At the point of maximum turning force, where the traction provided by the tires is at its limit, those two forces must be equal:
> mv2/r = μmg
> ...


Where I come from, we would say you are "talking without knowing" (in polite company). It is very common.


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## LostViking (Jul 18, 2008)

This is actually one of the most interesting threads I've read here in a long time (bickering and one-ups manship aside)- so my thanks to all of you for your input.

I'm not a racer by any means, but still hate the way I tend to bleed speed while turning - and then have to rev up again to regain what was lost - so I'm finding this discussion very enlightening.


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## Local Hero (Jul 8, 2010)

aclinjury said:


> I think you go watch lots of those 125cc 2-stoker racing. It'll answer much of your questions.


No. That is not an answer. 

Think hard on why a motorcycle stands up when the throttle is let off. Do not argue just for the sake of arguing. Do not assign reading homework or tell me to go watch some video on 125cc races. Think about it and you will understand what I am talking about. 

To others reading, I just wanted to point out that one of the reasons why a motorcycle can lean so far into a turn is that the power is being applied to the rear wheel. Too much power and it will slide out and low-side. Release the power and it strightens up or highsides. Why is that? It's much more than just a deceleration. The tires do not become any more or less sticky. 

I would not mind being corrected here but see no reason to change my position. I think my explanation and examples so far as sufficient to show that motorcycles and bicycles experience different forces while cornering. The power and torque on the rear wheel of the motorcycle creates additional forces. Since there is no power going to the rear wheel of bicycles during turns, the analogy between bicycles and motorcycles can only go so far.


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## charlox5 (Jan 31, 2011)

Local Hero said:


> Many things are similar between motorcycles and bicycles. Some things are different.
> 
> When you are cornering on a bicycle you are not putting down the power.
> 
> ...


Motorcycles need "maintenance throttle" to maintain constant speed through a turn because of the energy lost to friction, drag, engine braking, etc. While a bicycle still decelerates in a corner, it is not nearly as dramatic is it would be going off throttle midcorner on a moto. But the fact remains that no motorcycle rider is going to be on the throttle before corner apex. Throttle application does not happen until you've reached corner apex and begin track out. So, at turn in (which is what this thread is about, going in hot) motorcycles and bicycles are either braking and turning in, or trailbraking into corner entry. 

Throttle is not what allows lean angle. Lean angle is going to be dictated by countersteering angle and weigh distribution. Maintenance throttle or the application of power to the rear wheel is what keeps the lean angle required for the given radius turn to be consistent--but Rossi can change his lean angle at any given point independent of the throttle, possibly to change his line or avoid debris, but there are limitations as to how much he can change, and whether it'll stick.

You are misunderstanding what happens in the highside on a motorcycle: Highsiding is a product of losing rear wheel traction (either as a result of too much power to the rear wheel, or the surface is slick)--and the sudden restoration of traction, which has the resulting effect of tossing you into the air like a rag doll. So during track out, if you're too aggressive on the throttle, and spin up the rear, and chop the throttle closed, that is the most common reason for highsiding on a motorcycle.


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## Local Hero (Jul 8, 2010)

charlox5 said:


> Motorcycles need "maintenance throttle" to maintain constant speed through a turn because of the energy lost to friction, drag, engine braking, etc. While a bicycle still decelerates in a corner, it is not nearly as dramatic is it would be going off throttle midcorner on a moto. But the fact remains that no motorcycle rider is going to be on the throttle before corner apex. Throttle application does not happen until you've reached corner apex and begin track out. So, at turn in (which is what this thread is about, going in hot) motorcycles and bicycles are either braking and turning in, or trailbraking into corner entry.
> 
> Throttle is not what allows lean angle. Lean angle is going to be dictated by countersteering angle and weigh distribution. Maintenance throttle or the application of power to the rear wheel is what keeps the lean angle required for the given radius turn to be consistent--but Rossi can change his lean angle at any given point independent of the throttle, possibly to change his line or avoid debris, but there are limitations as to how much he can change, and whether it'll stick.
> 
> You are misunderstanding what happens in the highside on a motorcycle: Highsiding is a product of losing rear wheel traction (either as a result of too much power to the rear wheel, or the surface is slick)--and the sudden restoration of traction, which has the resulting effect of tossing you into the air like a rag doll. So during track out, if you're too aggressive on the throttle, and spin up the rear, and chop the throttle closed, that is the most common reason for highsiding on a motorcycle.


Thanks. Can you explain why a motorcycle stands up when the throttle is released? 

Is it possible to high-side without first losing traction? 

What is the difference between throttle and maintenance throttle?


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## charlox5 (Jan 31, 2011)

Local Hero said:


> Thanks. Can you explain why a motorcycle stands up when the throttle is released?
> 
> Is it possible to high-side without first losing traction?
> 
> What is the difference between throttle and maintenance throttle?


1. I think it's important to distinguish between types of deceleration--if you are cranked over on a motorcycle and you release throttle, the bike will not stand itself up. In fact, there are many instances on a race track where lean angle is increased when the bike is off throttle (Say, during a pass) and the bike does not fight you. However, when applying the brakes, the gyroscopic effect takes over as the spinning mass of the front wheel is acted upon by the force exerted by the brakes, and will stand the bike up to conserve angular momentum. 

2. Well the right kind of impact could high side you, but generally speaking it is almost always caused by a loss of traction, followed by the regaining of traction--technically by either wheel or both. 

3. Maintenance throttle is a non-scientific term to describe the amount of throttle it requires to keep the speed of a motorcycle constant in a turn. Not sure if anyone uses it out in the world, but the trackday instructors i know throw it around pretty often.


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## foto (Feb 7, 2005)

high sides are scary, and that is second biggest reason I race bicycles and not motos...


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## foto (Feb 7, 2005)

charlox5 said:


> 1. I think it's important to distinguish between types of deceleration--if you are cranked over on a motorcycle and you release throttle, the bike will not stand itself up. In fact, there are many instances on a race track where lean angle is increased when the bike is off throttle (Say, during a pass) and the bike does not fight you. However, when applying the brakes, the gyroscopic effect takes over as the spinning mass of the front wheel is acted upon by the force exerted by the brakes, and will stand the bike up to conserve angular momentum.
> 
> 2. Well the right kind of impact could high side you, but generally speaking it is almost always caused by a loss of traction, followed by the regaining of traction--technically by either wheel or both.
> 
> 3. Maintenance throttle is a non-scientific term to describe the amount of throttle it requires to keep the speed of a motorcycle constant in a turn. Not sure if anyone uses it out in the world, but the trackday instructors i know throw it around pretty often.


How about if you over-steer a turn, that could cause a highside...right?


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## charlox5 (Jan 31, 2011)

foto said:


> How about if you over-steer a turn, that could cause a highside...right?


Clarify "over-steer" for me. Is this turning so much you overwhelm available grip? Or something else?

Even still, I don't think you can highside until there's something that causes the bike to change directions in the vertical axis quickly. 

I suppose if you took brake force application to the extreme, as well as the angular momentum case, and had an instance where you put the brakes on hard enough and fast enough to snap the bike upright with enough force to throw you off, you could do it without losing traction, but i'm not sure anything like that exists


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## foto (Feb 7, 2005)

charlox5 said:


> Clarify "over-steer" for me. Is this turning so much you overwhelm available grip? Or something else?
> 
> Even still, I don't think you can highside until there's something that causes the bike to change directions in the vertical axis quickly.
> 
> I suppose if you took brake force application to the extreme, as well as the angular momentum case, and had an instance where you put the brakes on hard enough and fast enough to snap the bike upright with enough force to throw you off, you could do it without losing traction, but i'm not sure anything like that exists


For example, you are riding through a long sweeping turn. If you quickly and violently drop the inside of the bike down, the front will dive in the direction you dropped it, but too fast for the bike to actually complete the turn, and the whole thing will highside.

Do you get what I mean? I don't know moto-speak...kinda like counter-steering but way too much?

And taking this mental picture one step further: If you are in a long sweeping turn, and you let off the gas, that would have the same effect as drastically leaning the bike over, or tightening the turning radius, to the point of the bike highsiding.


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## charlox5 (Jan 31, 2011)

foto said:


> For example, you are riding through a long sweeping turn. If you quickly and violently drop the inside of the bike down, the front will dive in the direction you dropped it, but too fast for the bike to actually complete the turn, and the whole thing will highside.
> 
> Do you get what I mean? I don't know moto-speak...


sure.

so in your example, when you change the yaw angle (what direction you're pointed) of the bike so quickly that the front wheel and rear wheel start going in different directions, this is only possible if one or both of the wheels is now slipping, and if the wheels keep slipping, you're lucky and you'll lowside. if the wheels suddenly regain traction, you'll highside.


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## foto (Feb 7, 2005)

charlox5 said:


> sure.
> 
> so in your example, when you change the yaw angle (what direction you're pointed) of the bike so quickly that the front wheel and rear wheel start going in different directions, this is only possible if one or both of the wheels is now slipping, and if the wheels keep slipping, you're lucky and you'll lowside. if the wheels suddenly regain traction, you'll highside.


Well wait a second. If the bike is turning, the wheels are going in two directions, every time. Whether you are skidding out or not.

The rear always pivots a little bit...

This is not the same as completely losing the rear end and then suddenly getting it back again.


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## foto (Feb 7, 2005)

Ok, how about this:

There are 2 variables that determine turning radius:

Lean angle
Velocity

At a constant velocity, and constant lean angle, the bike will travel a constant radius.

The lower the velocity, the tighter the radius for a constant lean angle. Thus, if you quickly roll off the throttle while in a turn, you are tightening the turning radius faster than the bike can handle, which compensates by reducing the lean angle very quickly, causing the high side.

I would guess that this is pretty hard to do on a bicycle...


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## Local Hero (Jul 8, 2010)

Would a motorcycle be able to maintain a steady lean throughout a turn without staying on the throttle?


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## Local Hero (Jul 8, 2010)

Also, I think the gyroscopic force that stands a bike up when the brakes are applied is the same force that leans the bike into turns when the throttle is applied.


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## charlox5 (Jan 31, 2011)

Creakyknees said:


> So, how do you reconcile these two statements?





foto said:


> Well wait a second. If the bike is turning, the wheels are going in two directions, every time. Whether you are skidding out or not.
> 
> The rear always pivots a little bit...
> 
> This is not the same as completely losing the rear end and then suddenly getting it back again.


yes the wheels are pointed in a different direction, but the resultant turn radius is the same for both of the wheels. remember that as a 2-wheeled vehicle turns at speed, the turn is caused by camber thrust from the profile of tires, not from the direction the wheels are pointed. (This is different at low speeds). This is why one would countersteer. 



foto said:


> Ok, how about this:
> 
> There are 2 variables that determine turning radius:
> 
> ...


If you were to roll off the throttle and maintain the same lean angle, the radius of the turn would decrease, but because the lean angle is the same, there is no force creating a moment to throw you off. haha don't make me draw a free body diagram!



Local Hero said:


> Would a motorcycle be able to maintain a steady lean throughout a turn without staying on the throttle?


yes, but the turn radius would decrease because of the resultant decrease in velocity due to engine braking, drag, etc. 



Local Hero said:


> Also, I think the gyroscopic force that stands a bike up when the brakes are applied is the same force that leans the bike into turns when the throttle is applied.


But without application of steering torque, or body lean, the bike does not lean aka, the bike doesn't want to lean over when throttle is applied in a straight line. And, quite the contrary to your idea, the rotating mass of the front wheel resists lean angle. 

My mastery or lack thereof of motorcycle dynamics is knowing coming into full display, lol. But, the basics of this is easily demonstrated while riding a motorcycle.


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## aclinjury (Sep 12, 2011)

foto said:


> You clearly are either incapable or unwilling to explain the physics. I am going to go with "incapable" until you convince me otherwise.


How about you go read up on the law of energy conservation? Apply yourself, instead of talking down others for not spoon feeding you.


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## aclinjury (Sep 12, 2011)

foto said:


> You mean like this?
> 
> https://www.google.com/search?q=cor...e.1.57j0l2j62l3.4691&sourceid=chrome&ie=UTF-8
> 
> ...


That's a system you're talking about. The system can have changes within itself and it would affect a particular instant/position. It's perfectly allowed and not violate any law.

Again, you don't grasp the difference between changes within a system and the total conservation of energy of the complete system. Like I said, you need to go read up. I feel like I'm trying to explain what the color red looks like to a blind person, only to have the blind person tell me that the color red looks like green to him. In his own mind, he is 100% correct. That's you.


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## aclinjury (Sep 12, 2011)

charlox5 said:


> Motorcycles need "maintenance throttle" to maintain constant speed through a turn because of the energy lost to friction, drag, engine braking, etc. While a bicycle still decelerates in a corner, it is not nearly as dramatic is it would be going off throttle midcorner on a moto. But the fact remains that no motorcycle rider is going to be on the throttle before corner apex. Throttle application does not happen until you've reached corner apex and begin track out. So, at turn in (which is what this thread is about, going in hot) motorcycles and bicycles are either braking and turning in, or trailbraking into corner entry.
> 
> Throttle is not what allows lean angle. Lean angle is going to be dictated by countersteering angle and weigh distribution. Maintenance throttle or the application of power to the rear wheel is what keeps the lean angle required for the given radius turn to be consistent--but Rossi can change his lean angle at any given point independent of the throttle, possibly to change his line or avoid debris, but there are limitations as to how much he can change, and whether it'll stick.
> 
> You are misunderstanding what happens in the highside on a motorcycle: Highsiding is a product of losing rear wheel traction (either as a result of too much power to the rear wheel, or the surface is slick)--and the sudden restoration of traction, which has the resulting effect of tossing you into the air like a rag doll. So during track out, if you're too aggressive on the throttle, and spin up the rear, and chop the throttle closed, that is the most common reason for highsiding on a motorcycle.


That statement is like basic motorcycle racing 101. I thought it would be obvious to anyone who talks about motorcycle.

I didn't take time to explain to Local Hero. Instead I told him to go watch 125cc 2-stroke in hope that he'll can see that when these guys initiate a turn in, their throttle is pretty much shut off (evident by the lack of engine sound), and that when they get on the throttle as the apex out, their engine would roar back to life, and the observer would clearly see this as self evident.

You do a well job explaining motorcycle physics.


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## aclinjury (Sep 12, 2011)

I will try to find a youtube clip of the downhiller Lawskill doing counter steering on a bicycle at 10 mph while the bike is lean over to the point it almost touches the ground.
It will open some eyes in here about bicycle control. I'll try to find it for yall.


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## AJL (Jul 9, 2009)

*The answer!*

Bicycle and motorcycle dynamics - Wikipedia, the free encyclopedia

Or, at least all the concepts and equations necessary. There are some interesting surprises about various assumptions (like gyroscopic effects being unimportant wrt bicycle stability).

Cheers!


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## AJL (Jul 9, 2009)

aclinjury said:


> I will try to find a youtube clip of the downhiller Lawskill doing counter steering on a bicycle at 10 mph while the bike is lean over to the point it almost touches the ground.
> It will open some eyes in here about bicycle control. I'll try to find it for yall.


Yes, that is interesting and is briefly mentioned in the above article. I used to do that as a sort of 'trick' riding on my fixie when I was a kid.


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## aclinjury (Sep 12, 2011)

AJL said:


> Bicycle and motorcycle dynamics - Wikipedia, the free encyclopedia
> 
> Or, at least all the concepts and equations necessary. There are some interesting surprises about various assumptions (like gyroscopic effects being unimportant wrt bicycle stability).
> 
> Cheers!


Very interesting wiki. It's a bit over my head with the equations, I haven't looked at equations like these in over a decade!

I think the one thing I took away from the wiki is the notion of *weight distribution.*

A bicycle is not a point mass, and some of the arguments here are arguing as if a bicycle is a point mass. It can be thought of as a point mass if the desire is to look at it as a whole system. 

However, in practice, a bicycle is far from a point mass, and often operated in conditions far from ideal (as these physics equations tend to assume). A bicycle has 2 wheels separated by a distance (wheelbase), with steering done only on the front wheel (not both wheel). You have different moments at work at the front and at the rear. Weight distribution affect tire deformation and therefore tire-ground contact patches, and hence also affect friction at each of these moment location (ie, the front and the rear ends).

Sure open my eyes as some of my previous thoughts and assumptions are not fully correct.

To me the bottom line is this. Turning a bicycle (or motorcycle) involves lots of body dynamics, or else we would not see pro cyclists and pro moto hanging off their bikes and shifting their bodies fore and aft depending what weight distribution they're trying to achieve. Spend 5 minutes learning from someone with real world experience will beat discussing physics equations on the interwebz for days on.


[edit:]

Foto, 

some of the stuff I argue with you are now not correct after reading the wiki posted by AJL. Some of the things you said also was not correctly understood by me.


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## aclinjury (Sep 12, 2011)

AJL said:


> Yes, that is interesting and is briefly mentioned in the above article. I used to do that as a sort of 'trick' riding on my fixie when I was a kid.


Well still can't find the video. Still trying though, it's an obscure video, but it opened my eyes when I saw it.

There's a cool trick that the bmx and downhill guys do a lot. Don't know the name of the trick, but it's where they lean on the front (load the front) to lighten the rear up a bit as they are coming into a turn, and they using their body (their hip and outside leg), they would "whip" the bike to break the rear end. I think it's called "cutties". I guess the idea is if the bike is going to slide anyway (because of the high speed and the corner), then maybe it's best to just initiate the rear end slide first before the bike will get a chance to slide unpredictably and slide out the front, and between rear end and front end sliding, it's better to have the rear end slide then front. Ideally you don't want any end sliding, but sometimes you just gotta force the issue if you wanna make the corner! Of course a lot easier to do when you're on dirt with big soft rubber and suspension than when you're on the road with skinny tires and a stiff frame lol.


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## Creakyknees (Sep 21, 2003)

this thread delivers.


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## Creakyknees (Sep 21, 2003)

aclinjury said:


> There's a cool trick that the bmx and downhill guys do a lot.


It's called a whip. As in, "OHHHH MY GOD LOOK AT THE WHIIIIPPP!!!!"






Seriously. You guys want to see what's possible, watch that video. Especially about 2:14 to 2:20.


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## charlox5 (Jan 31, 2011)

supermoto guys (and pro moto racers with huge attachments) do something similar called "backing it in", where you break the rear wheel loose to get the bike pointed in the right direction, then get on the gas. as we talked about earlier, do it wrong and you're taking Air Lorenzo to a land called broken ankles.


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