Tagging this ancient comment to say: many explanations of swaybars neglect to mention what Jason shows at the end, which is that the bar is _fixed_ to the chassis inboard of the suspension. This constrains the motion of the bar (or that central section) to only rotation, meaning it can only rotate (when both wheels hit a bump) or twist (when one wheel hits a bump).
Anti-roll bars reduce body roll under applied lateral acceleration (i.e. in cornering), which DOES reduce the static WEIGHT transfer (i.e. weight transfer due to lateral movement of the body CoG). However, an anti-roll bar will increase roll stiffness on the axle that it is mounted to which will increase LOAD transfer (i.e. the reaction load, at the outside tyre contact patch, of the vehicle lateral accelertion). Due to tyre load sensitivity this reduces overall grip of the axle. Thus in order to dial out (for example) mid-corner understeer on a vehicle you would tend to soften the front anti-roll bar to reduce lateral load transfer across that axle, decrease the delta in tyre loading and thereby increase overall grip across the axle.
This was a very young Jason, who now knows that reducing body roll does NOT reduce weight transfer. That can only be reduced by either lowering the center of gravity (CG) of the car, or by increasing the track width.
The green control arm is mounted to the frame and can move the tire vertically. I explain the torque reaction in the blue bar using my hand and arm, in the video. As one side is lifted, it causes the blue bar to twist, making the other side lift as well.
That's one of the great things about Forza! And another benefit is understanding the effects of varying these things without worrying about damaging your own car. Find out how it acts based on Forza's physics engine (which is pretty darn accurate) and build a better understanding for when one day you can apply it to the real world.
this is just NOT a good explanation. Delete this video and try to make it again. Ask someone who doesn't understand the component and test them after your video. If they don't understand, think of ways to remake your point. That YOU UNDERSTAND DOESN'T MATTER. You did when you started, & used your own metaphor to judge it.
I'm actually working on a website right now, and one of the articles I've written is a comparison of going to school for mechanical engineering, automotive engineering, or a technical education in mechanics. The website is taking longer than it should, but when it's released I'll be making a video on it, and so you will surely know.
The effects of the ARB would remain the same. The difference is since the Porsche is one of few vehicles with a rear mounted engine (behind the drive axle) it has a tendency to oversteer since there is weight at the rear. Porsches in general seem to be pretty well balanced and not in need of adjustments unless you simply want to eliminate understeer completely, but that makes the car more difficult to drive.
Thank you for pointing this out, the wiki statement is logical. However, as a body rolls, the CG of the car also moves with it, so I believe a rolling body (if extreme enough) could slightly alter the CG, therefore altering the weight distribution. If the roll is minimal, then certainly your statement would hold nearly true. Interesting to think about, thank you for challenging my video.
Woops! You are correct. Assuming the travel is the same (which it would be) a shorter arm would mean a greater angle change of the ARB, thus transferring a greater torque to the opposing side.
An ARB is not necessary, and depending on your spring stiffness/shock damping they can be eliminated. There may be a weight difference between the auto/manual, or a different spring/shock set-up that is the reasoning behind not having the sway bar in the manual. Or possibly to reduce understeer in the manual, since manuals are more of driver's cars than autos.
Yes, they basically do the job of a solid axle, which is fine on flat pavement, but if they're too stiff and you're on a bumpy road, it's definitely not ideal. Hence most road cars have fairly light ARBs.
Well it would vary, but generally cars are set-up for understeer since it is typically more safe. So the set-up would likely follow my descriptions and create a light amount of understeer.
Basically you just increase (or decrease) the length of the lever arm. The longer the lever arm (where it connects to the control arm) the greater the torque which passes to the other side, essentially making the ARM more stiff.
You are correct, the stronger the ARB the less independent your suspension becomes. The independence is sacrificed for reduced roll. On a track, it can be worthwhile. On the street I'd question having an ARB that was too heavy.
They are all made from a similar alloy steel. And you don't significantly change the weight transfer by adding more roll stiffness, a lower CG and wider track will do that.
Slip angle is the angle between the direction a tire is traveling and the direction the tire is pointing. When the tire is *slipping* there is a difference in these two directions.
Both can achieve it, though typically ARBs are a cheaper way of doing it. The downside is your wheels start to lose their independence with heavy ARBs.
Part 2: Camber does not fix balancing issues, it changes cornering ability so be careful with that, you might make your car better in corners, but if you get it wrong you might make it a lot worse and also it will increase your tire wear. Shocks don't affect tire balance, but you might get a similar effect (shaking) if your shocks are bad, but this usually is noticeable only when taking corners, but not if you drive in a straight line. Hope this helps, cheers
OK. Right off: Anti-roll bars DO NOT reduce weight transfer by more than a tiny, tiny smidgeon. Weight or load transfer is an unavoidable consequence of the vehicle's centre of mass being above ground level, where the lateral forces are applied. All anti-roll bars do is to get you to the amount of roll that will equally oppose the torque created by those lateral forces at a smaller total roll
ARBs do, however, contribute to either front or rear roll stiffness. ARBs increase roll stiffness of the end they are mounted on. Increased stiffness causes increased load transfer on the end that becomes stiffer, in a curve. Load transfer decreases across the other end, so that the net transfer is the same (except for some very minor effects from CG migration). Think "stiffness attracts load transfer" and you'll have it right. If, say, you stiffen a rear swaybar, you'll increase the load transfer between the rear wheels and decrease it between the front ones. This has the effect of giving less traction in the rear and more in the front. There are also other effects from the reduction in body roll including improved camber, that can affect vehicle balance in other ways. Millikan (the younger) was my vehicle dynamics teacher. Awesome guy.
They're not totally necessary if the suspension is good enough as is, but it's cheaper to make a good suspension with roll bars than it is with different shocks/links/springs. Hence why some supercars can get away without using them (for a price, of course).
Note to Stu continued... this describes the Mechanical grip portion of traction. EE discusses the importance of controlling roll (with stiff ARBs and good suspension geometry) to keep prototype and formula cars "flat" to the road in order to maintain their Aerodynamic grip. A good laymens book on all this comes from Carroll Smith called Tune to Win - Smith was Carroll Shelbys head mechanic for the GT40 program winning Lemans from 1966 - 1969. The recent SAE textbooks go over the top with math
They would reduce the roll of the car significantly, however the suspensions would lose some of their "independence" as well. It's fine if the track is perfectly smooth, but for bumps, holes, imperfections, it's more of a balancing act of getting it just right.
Stu, if you are just looking at the front end of the car, the ARB will reduce understeer by controlling tire camber. The driver likes it because the car is responsive and takes a set quickly. However, anytime you transfer weight from one side of the car to the other, you reduce the total traction the tires develop. So a really stiff front ARB transfers a lot of weight to the front outside tire (and the inside rear tire from diagonal weight jack). Continued in next post...
The result is fairly small indeed but the pneumatic tire does not develop grip linearly to the applied load. The load sensitivity of tires actually make even the small amounts of weight transfer affect the grip levels noticeably and as a whole the "rubber grip" is more complex phenomenon than often realised. The mentioned wheel posture, camber changes for example, can be dealt to an extent in the suspension geometry itself, though it is of course affected by the roll nonetheless.
On the "yes to lifting" part, you can see this effect if you have unbalanced ARBs. For example a car with soft springs, and a very stiff front ARB combined with a very soft (or no) rear ARB can lead to not having enough total roll resistance to prevent body roll, but since the front suspension is tied together the inside front does indeed lift off completely.
Wish I could answer your question better, but I don't have any experience with it. I'd try searching for forums for your car, where people who have used various set-ups explain the pros and cons. Best of luck!
Hakan - you must look at the front pair of tires and the rear pair of tires vs. any single tire to understand over/understeer balance. A CanAm car I studied had 540 pounds of force on each rear tire going straight. In the turn, it transferred 328 pounds to the outside tire. The coefficient of friction does increase with wait, but relatively less and less with each additional pound of force added to the tire. In a straight line, the tires had 1.4G of grip, but in the turn, now only 1.3G....
i must say, the way you explain is really really simple and good! thanks a lot man. one more thing to appreciate - at the end of the video you show the component (the one you explain in the video) in real life eg. Roll Bar in this one. that really helps man!
I watched 4 other videos with a higher watch count than this one but none of them made me understand exactly how a sway bar works like this one did. Good Job!
Young and just starting out on his videos. Seems like he was just recording with a smartphone first before adding microphones and camera for better video quality. Engineer explain has come a long way for sure
There is also wheel droop: the opposite of the compression action you described. A bar will also lessen a wheel's ability to droop if it's opposing wheel is compressed. Some cars can lift the inside wheel during hard cornering caused at least some of the time by the anti roll bar. Thanks for the explanation. A driving instructor just told me to disconnect the rear bar to lessen under steer and I had to double check that that is wrong.
Thank you for the video, current studying mechanical engineering and they have really helped. Also I love the way you explain things visually- you're a fresh take on lecturers :P x
Hakan (cont) - You are right, the outside tire is developing more grip, but the rear pair of tires develops less overall grip. A stiffer rear roll bar increases outside rear tire grip, but results in less total rear tire grip* (*see comments below regarding Camber control) - an adjustment toward oversteer.
1. Body roll makes little difference to toppling over in steady state situations. The COG does not move much laterally. It is dynamic situations where a lack of roll control can result in toppling, but the skill level of the driver plays a large role here. 2. The crux difference between fitting stiffer springs versus anti roll bars (or stiffer anti roll bars) is double bump stiffness, like when you go over a speed bump or expansion joint in the road. Everything else is the same or similar.
I’m getting the opposite effect with my car. RWD Dodge Magnum RT. I have the Touring Suspension as was looking at upgrading for less roll and less float. I got the Bilstein B6 shocks and struts, which are awesome, kept factory springs, and was going to swap in a 30mm sway bar from a Performance Suspension model or SRT8. Mine has a 27mm ARB. But while going through LKQ to get a 30mm I saw a police spec Charger. All of my suspension is the same except for the 32mm sway bar. It made a significant difference. The car is far more settled especially at highway speeds. But one particular thing I always wanted my car to be able to do it now can do. And I was t expecting this. I like the ability to spin a car around on the tightest axis possible, basically leaving the inside front tire on one pivot point and rotating the rear. Well now, that’s a breeze after putting that sway bar in. Why? It’s supposed to reduce oversteer, but now it’s easy to oversteer it from a standstill, and at speed I ca. break the rear end loose, the front end is incredibly tight, and the car has transformed into more like an M5 kind of ride and handling. But why did my much stiffer ARB increase oversteer AND reduce understeer considerably?
First, thanks for the videos. They are very good and I have learned much from them. However, anti roll bars ALWAYS INCREASE weight transfer in roll. In racing this can be seen when the inside wheel is completely pulled off the circuit by the stiff ARB, in which case, the outside wheel is carrying all the load. Ultimately the ARB is good by maintaining good wheel camber on the outside wheel - leading to maximum tire contact patch size/traction and increasing the cars transient responsiveness
Ahhh I understand now. I used to think a roll bar was a small roll cage type thing for convertibles/karts that would go directly behind the seat headrests. Thanks dude.
the primary reason for ARBs is to control tire camber on the outside tire during a turn. You could achieve the same with very stiff springs; however softer springs give better tire compliance and grip; therefore, we use ARBs to control car roll in turns. You only want bars stiff enough to control tire camber at the speeds you drive - slow speed = softer ARBs
You can make diy adjustable roll bars by making adjustable droplinks. Usually when a car is lowered with coilovers or lowering springs the antiroll bar turns too much "upwards" when car's weight is on suspension. Therefore you'll need shorter droplinks to make the wheel lifting effect faster on the inner curve side. If you know what I mean..
Note to Stu continued... and if there is no rear ARB, the rear tires have more overall traction than the front which is the definition of understeer. Lateral Load Transfer = Lateral acceleration in G's * weight * Center of Gravity height / track width. A sports car cornering above 1G transfers 70+% of its weight to the outside tires. Having that outside tire flat against the road ends up to be more important that anything happening with the inside tire. Continued...
I'm curious about how you change your slip angle with an anti-roll bar? What you should had say is when you change the anti-roll balance (front/rear) you change the load transfer balance (front/rear). Where you have the stiffer anti-roll bar you'll have the more load transfer so the opposite track will have more grip.
ARBs do affect weight transfer and the above equation does not tell the whole story when the vehicle's body rolls. Sprung and unsprung masses must be taken into account separately and we need to also determine roll centers so that the weight transfers can be calculated. Then we can continue to roll resistance where springs and ARBs come into play and get the final distribution of weight transfer in roll.
I don't know the full reasoning, but I know that the suspension in the MP4-12C isn't conventional, it uses hydraulic controlled suspension and dual-chamber shocks that bleed excess pressure from one side of the shock to the other... Some people explain it as adjustable spring ratios, which is also why the car rides so comfortably when its in normal and is so stiff in track mode. The hydraulics manage the body roll as well.
Anti- sway/ anti - roll bars provide a means to control weight distribution and mitigate "body roll" around the sides, front and rear of vehicle particularly when cornering thereby maintaining stability and contact with the road.
Great explanation! I wanted to learn about this component and this video was straight and to the point without being any longer than it needed to be. Thank you
While it does add a linkage between the wheels at one end, an ARB is the *opposite* of a solid axle. A solid axle causes cross-side jacking on compression, magnified by the inboard position of the spring perches. An ARB causes cross-side compression, along with a reduction of body roll.
Continued: If you get added grip from increasing total roll stiffness (without changing tlltd) it will be due to minimizing the movement of poor suspension geometry. More likely though, you will lose grip due to minimizing the movement of *good* suspension geometry, and you will be much more likely to lose grip driving over a bump in the road as you've taken your independent suspension and then linked it up again (assuming you used a ARB to increase roll stiffness) left to right.
ty so much man , i am a fast virtual pilot , but i am terrible and setup , i just test and test ,but normaly i dont know what to do ,This helps a lot to know what i must to change .
Well yes in a way, if you have too much camber, the tire wear will not be even, the inside part of the tire will wear faster and more than the outside. Adjustable camber kit could solve this problem. Another (cheaper) way is to compensate with adjusting your "toe", this will only minimize the tire wear, but the tire will still wear more on the inside than on the outside. What car model are we talking about ?
Quick question: Wouldn't an ARB defeat the purpose of independent suspension? One consequence of installing an ARB is that what happens to one wheel will happen to the other and thus a suspension system such as a double wishbone isn't truly independent. Am I thinking about this the wrong way? Thanks for the awesome videos by the way! I've learned more from you videos than from talking with all my wrench head buddies.
Good explanation, but I think your diagram would have made more sense if you'd shown that the anti-roll bar is clamped along its main length in order to only allow it to rotate.
Dear Jason, thank You very much for explaining anti-roll (balancing) bar! I was watching every your video from 2017 onward, but this one dates back to 2012. You look like a kid here, what a discovery :D
I removed my front arb in my Seat Leon Cupra R as it understeers from oem setup. I also got a larger rear arb and the chassis has a MUCH more neutral balance in the corners. Still a little push but that's more down to how the Haldex engages the rear tires.
I love how Jason went from awkward nerdy teenager to nerdy middle-aged man in the short span of 7 years.
Read too many youtube comments.
atlucas1 😂
Dude that's actually super funny lol
InstaBlaster
The last 30 seconds was gold. That 30 seconds made everything clear to me. Thanks!
Tagging this ancient comment to say: many explanations of swaybars neglect to mention what Jason shows at the end, which is that the bar is _fixed_ to the chassis inboard of the suspension. This constrains the motion of the bar (or that central section) to only rotation, meaning it can only rotate (when both wheels hit a bump) or twist (when one wheel hits a bump).
Anti-roll bars reduce body roll under applied lateral acceleration (i.e. in cornering), which DOES reduce the static WEIGHT transfer (i.e. weight transfer due to lateral movement of the body CoG). However, an anti-roll bar will increase roll stiffness on the axle that it is mounted to which will increase LOAD transfer (i.e. the reaction load, at the outside tyre contact patch, of the vehicle lateral accelertion). Due to tyre load sensitivity this reduces overall grip of the axle. Thus in order to dial out (for example) mid-corner understeer on a vehicle you would tend to soften the front anti-roll bar to reduce lateral load transfer across that axle, decrease the delta in tyre loading and thereby increase overall grip across the axle.
Will this anti-roll bars can be used in off-road vehicles is this necessary for off-road vehicles??
You have answered a question I thought I was going to have to research, thank you good sir
Word
This was a very young Jason, who now knows that reducing body roll does NOT reduce weight transfer. That can only be reduced by either lowering the center of gravity (CG) of the car, or by increasing the track width.
So remove sway bars to maximize roll for most traction?
The green control arm is mounted to the frame and can move the tire vertically. I explain the torque reaction in the blue bar using my hand and arm, in the video. As one side is lifted, it causes the blue bar to twist, making the other side lift as well.
That's one of the great things about Forza! And another benefit is understanding the effects of varying these things without worrying about damaging your own car. Find out how it acts based on Forza's physics engine (which is pretty darn accurate) and build a better understanding for when one day you can apply it to the real world.
this is just NOT a good explanation. Delete this video and try to make it again.
Ask someone who doesn't understand the component and test them after your video.
If they don't understand, think of ways to remake your point.
That YOU UNDERSTAND DOESN'T MATTER. You did when you started, & used your own metaphor to judge it.
Why are u wearing a helmet
lmao
@ west wood - What a jerk.
Dick head
He's always ready to race
Rick King it’s a joke Asshat
Well, the goal is to keep the car level, so yes. But if your roll bars are too stiff, you could pick up an inside tire off the ground when cornering.
I'm actually working on a website right now, and one of the articles I've written is a comparison of going to school for mechanical engineering, automotive engineering, or a technical education in mechanics. The website is taking longer than it should, but when it's released I'll be making a video on it, and so you will surely know.
The effects of the ARB would remain the same. The difference is since the Porsche is one of few vehicles with a rear mounted engine (behind the drive axle) it has a tendency to oversteer since there is weight at the rear. Porsches in general seem to be pretty well balanced and not in need of adjustments unless you simply want to eliminate understeer completely, but that makes the car more difficult to drive.
Thank you for pointing this out, the wiki statement is logical. However, as a body rolls, the CG of the car also moves with it, so I believe a rolling body (if extreme enough) could slightly alter the CG, therefore altering the weight distribution. If the roll is minimal, then certainly your statement would hold nearly true. Interesting to think about, thank you for challenging my video.
Woops! You are correct. Assuming the travel is the same (which it would be) a shorter arm would mean a greater angle change of the ARB, thus transferring a greater torque to the opposing side.
An ARB is not necessary, and depending on your spring stiffness/shock damping they can be eliminated. There may be a weight difference between the auto/manual, or a different spring/shock set-up that is the reasoning behind not having the sway bar in the manual. Or possibly to reduce understeer in the manual, since manuals are more of driver's cars than autos.
What a perfectly timed question, I just posted a video on strut bars an hour ago! :) Yes, they are different.
Glad to hear, cheers!
Yes, they basically do the job of a solid axle, which is fine on flat pavement, but if they're too stiff and you're on a bumpy road, it's definitely not ideal. Hence most road cars have fairly light ARBs.
Well it would vary, but generally cars are set-up for understeer since it is typically more safe. So the set-up would likely follow my descriptions and create a light amount of understeer.
Basically you just increase (or decrease) the length of the lever arm. The longer the lever arm (where it connects to the control arm) the greater the torque which passes to the other side, essentially making the ARM more stiff.
You are correct, the stronger the ARB the less independent your suspension becomes. The independence is sacrificed for reduced roll. On a track, it can be worthwhile. On the street I'd question having an ARB that was too heavy.
Different materials, different thicknesses; there are also some that are adjustable.
They are all made from a similar alloy steel. And you don't significantly change the weight transfer by adding more roll stiffness, a lower CG and wider track will do that.
Debating if I should buy a rear sway for my '07 Eclipse GT. Completely stock suspension, understeers like a giraffe on rollerskates.
@Down Shifts too late, it's fully built now lol
@Down Shifts nah.
Slip angle is the angle between the direction a tire is traveling and the direction the tire is pointing. When the tire is *slipping* there is a difference in these two directions.
What I mean by increase is basically replace with a stiffer sway bar. Or, in the case of racing roll bars, some are adjustable.
watching in 2019, wondering why there's a child on my screen? Keep it up
Jason..this man right here is a living legend. Theres no nonsense. just pure knowledge here
Both can achieve it, though typically ARBs are a cheaper way of doing it. The downside is your wheels start to lose their independence with heavy ARBs.
I was familiar with your other videos and I searched for this question. It was cool see you from 2012. Keep up the good work!
Part 2: Camber does not fix balancing issues, it changes cornering ability so be careful with that, you might make your car better in corners, but if you get it wrong you might make it a lot worse and also it will increase your tire wear.
Shocks don't affect tire balance, but you might get a similar effect (shaking) if your shocks are bad, but this usually is noticeable only when taking corners, but not if you drive in a straight line.
Hope this helps, cheers
OK. Right off:
Anti-roll bars DO NOT reduce weight transfer by more than a tiny, tiny smidgeon. Weight or load transfer is an unavoidable consequence of the vehicle's centre of mass being above ground level, where the lateral forces are applied. All anti-roll bars do is to get you to the amount of roll that will equally oppose the torque created by those lateral forces at a smaller total roll
+Alan Baker i see u have read race car vehicle dynamics :P
+08yannch More than a time or two, yeah... :-)
ARBs do, however, contribute to either front or rear roll stiffness.
ARBs increase roll stiffness of the end they are mounted on. Increased stiffness causes increased load transfer on the end that becomes stiffer, in a curve. Load transfer decreases across the other end, so that the net transfer is the same (except for some very minor effects from CG migration).
Think "stiffness attracts load transfer" and you'll have it right. If, say, you stiffen a rear swaybar, you'll increase the load transfer between the rear wheels and decrease it between the front ones. This has the effect of giving less traction in the rear and more in the front. There are also other effects from the reduction in body roll including improved camber, that can affect vehicle balance in other ways.
Millikan (the younger) was my vehicle dynamics teacher. Awesome guy.
dude there is no weight transfer in a car
@@DasKloputzer ....... Can't be serious.?
They're not totally necessary if the suspension is good enough as is, but it's cheaper to make a good suspension with roll bars than it is with different shocks/links/springs. Hence why some supercars can get away without using them (for a price, of course).
Note to Stu continued... this describes the Mechanical grip portion of traction. EE discusses the importance of controlling roll (with stiff ARBs and good suspension geometry) to keep prototype and formula cars "flat" to the road in order to maintain their Aerodynamic grip. A good laymens book on all this comes from Carroll Smith called Tune to Win - Smith was Carroll Shelbys head mechanic for the GT40 program winning Lemans from 1966 - 1969. The recent SAE textbooks go over the top with math
They would reduce the roll of the car significantly, however the suspensions would lose some of their "independence" as well. It's fine if the track is perfectly smooth, but for bumps, holes, imperfections, it's more of a balancing act of getting it just right.
Glad to hear, appreciate you watching!
Perhaps eventually, thanks for watching!
Stu, if you are just looking at the front end of the car, the ARB will reduce understeer by controlling tire camber. The driver likes it because the car is responsive and takes a set quickly. However, anytime you transfer weight from one side of the car to the other, you reduce the total traction the tires develop. So a really stiff front ARB transfers a lot of weight to the front outside tire (and the inside rear tire from diagonal weight jack). Continued in next post...
The result is fairly small indeed but the pneumatic tire does not develop grip linearly to the applied load. The load sensitivity of tires actually make even the small amounts of weight transfer affect the grip levels noticeably and as a whole the "rubber grip" is more complex phenomenon than often realised. The mentioned wheel posture, camber changes for example, can be dealt to an extent in the suspension geometry itself, though it is of course affected by the roll nonetheless.
Correct, the movement of the CG is minimal thus weight transfer is fairly insignificant.
On the "yes to lifting" part, you can see this effect if you have unbalanced ARBs. For example a car with soft springs, and a very stiff front ARB combined with a very soft (or no) rear ARB can lead to not having enough total roll resistance to prevent body roll, but since the front suspension is tied together the inside front does indeed lift off completely.
No, it's just an illusion that I've added in to my 100+ videos. :)
Haha, yes, yes I do.
This guy explains stuff so well.
Wish I could answer your question better, but I don't have any experience with it. I'd try searching for forums for your car, where people who have used various set-ups explain the pros and cons. Best of luck!
THANKS, BEST EXPLAINED ON UA-cam SO FAR!
Hakan - you must look at the front pair of tires and the rear pair of tires vs. any single tire to understand over/understeer balance. A CanAm car I studied had 540 pounds of force on each rear tire going straight. In the turn, it transferred 328 pounds to the outside tire. The coefficient of friction does increase with wait, but relatively less and less with each additional pound of force added to the tire. In a straight line, the tires had 1.4G of grip, but in the turn, now only 1.3G....
i must say, the way you explain is really really simple and good! thanks a lot man.
one more thing to appreciate - at the end of the video you show the component (the one you explain in the video) in real life eg. Roll Bar in this one. that really helps man!
You make it so simple with just hand drawings. Kudos.
Sure, for now you can check out my video "stability control." I go over it in that video.
This guy just made me understand something I've been trying months to do in just 3 minutes, thanks :)
I watched 4 other videos with a higher watch count than this one but none of them made me understand exactly how a sway bar works like this one did. Good Job!
You are so yong back then
Siqi Zhu not sure this counts as a compliment. You looks so young!... in your old videos
Young and just starting out on his videos. Seems like he was just recording with a smartphone first before adding microphones and camera for better video quality. Engineer explain has come a long way for sure
Why do I feel like I'm getting "Deja Vu" reading this comment..
He is 65 or something. Its insane
I have been watching your stuff for the last two years, but this is glorious!
I wanted to put stiffer sway bars on my fwd car. Now I realize that it is probably not a good idea. Thank you Jason, for showing me the light.
Thanks for subscribing!
There is also wheel droop: the opposite of the compression action you described. A bar will also lessen a wheel's ability to droop if it's opposing wheel is compressed. Some cars can lift the inside wheel during hard cornering caused at least some of the time by the anti roll bar.
Thanks for the explanation. A driving instructor just told me to disconnect the rear bar to lessen under steer and I had to double check that that is wrong.
even after 10 years, very informative video for sway bars. 10/10
Could be but I'm not sure. I'd check forums and see what set-ups others have done.
I would agree, yes.
Thank you for the video, current studying mechanical engineering and they have really helped. Also I love the way you explain things visually- you're a fresh take on lecturers :P x
You are welcome!
Hakan (cont) - You are right, the outside tire is developing more grip, but the rear pair of tires develops less overall grip. A stiffer rear roll bar increases outside rear tire grip, but results in less total rear tire grip* (*see comments below regarding Camber control) - an adjustment toward oversteer.
1. Body roll makes little difference to toppling over in steady state situations. The COG does not move much laterally. It is dynamic situations where a lack of roll control can result in toppling, but the skill level of the driver plays a large role here.
2. The crux difference between fitting stiffer springs versus anti roll bars (or stiffer anti roll bars) is double bump stiffness, like when you go over a speed bump or expansion joint in the road. Everything else is the same or similar.
I’m getting the opposite effect with my car. RWD Dodge Magnum RT. I have the Touring Suspension as was looking at upgrading for less roll and less float. I got the Bilstein B6 shocks and struts, which are awesome, kept factory springs, and was going to swap in a 30mm sway bar from a Performance Suspension model or SRT8. Mine has a 27mm ARB. But while going through LKQ to get a 30mm I saw a police spec Charger. All of my suspension is the same except for the 32mm sway bar. It made a significant difference. The car is far more settled especially at highway speeds. But one particular thing I always wanted my car to be able to do it now can do. And I was t expecting this. I like the ability to spin a car around on the tightest axis possible, basically leaving the inside front tire on one pivot point and rotating the rear. Well now, that’s a breeze after putting that sway bar in. Why? It’s supposed to reduce oversteer, but now it’s easy to oversteer it from a standstill, and at speed I ca. break the rear end loose, the front end is incredibly tight, and the car has transformed into more like an M5 kind of ride and handling. But why did my much stiffer ARB increase oversteer AND reduce understeer considerably?
Thank you for explaining how the anti-roll bars work so well!
Thank you! Best of luck with your engineering!
First, thanks for the videos. They are very good and I have learned much from them. However, anti roll bars ALWAYS INCREASE weight transfer in roll. In racing this can be seen when the inside wheel is completely pulled off the circuit by the stiff ARB, in which case, the outside wheel is carrying all the load. Ultimately the ARB is good by maintaining good wheel camber on the outside wheel - leading to maximum tire contact patch size/traction and increasing the cars transient responsiveness
Ahhh I understand now. I used to think a roll bar was a small roll cage type thing for convertibles/karts that would go directly behind the seat headrests. Thanks dude.
amazing explanation, came here after Rosberg's anti-roll bar problem in the 2013 Chinese F1 Grand Prix.
Wow...Congratulations on your achievements! Well earned.
the primary reason for ARBs is to control tire camber on the outside tire during a turn. You could achieve the same with very stiff springs; however softer springs give better tire compliance and grip; therefore, we use ARBs to control car roll in turns. You only want bars stiff enough to control tire camber at the speeds you drive - slow speed = softer ARBs
You can make diy adjustable roll bars by making adjustable droplinks. Usually when a car is lowered with coilovers or lowering springs the antiroll bar turns too much "upwards" when car's weight is on suspension. Therefore you'll need shorter droplinks to make the wheel lifting effect faster on the inner curve side. If you know what I mean..
before this video i didnt even know what swaybar was Now i even know how to change the handling of car By changing them
Starts at 0:52
Note to Stu continued... and if there is no rear ARB, the rear tires have more overall traction than the front which is the definition of understeer. Lateral Load Transfer = Lateral acceleration in G's * weight * Center of Gravity height / track width. A sports car cornering above 1G transfers 70+% of its weight to the outside tires. Having that outside tire flat against the road ends up to be more important that anything happening with the inside tire. Continued...
Bought my car in high school, in cash. Type R was not an option, though it's an awesome car.
I'm curious about how you change your slip angle with an anti-roll bar?
What you should had say is when you change the anti-roll balance (front/rear) you change the load transfer balance (front/rear). Where you have the stiffer anti-roll bar you'll have the more load transfer so the opposite track will have more grip.
I would use newer images but don't feel like chasing copyright permissions. All the images I use are pictures I took, thus have copyright for.
ARBs do affect weight transfer and the above equation does not tell the whole story when the vehicle's body rolls. Sprung and unsprung masses must be taken into account separately and we need to also determine roll centers so that the weight transfers can be calculated. Then we can continue to roll resistance where springs and ARBs come into play and get the final distribution of weight transfer in roll.
I don't know the full reasoning, but I know that the suspension in the MP4-12C isn't conventional, it uses hydraulic controlled suspension and dual-chamber shocks that bleed excess pressure from one side of the shock to the other... Some people explain it as adjustable spring ratios, which is also why the car rides so comfortably when its in normal and is so stiff in track mode. The hydraulics manage the body roll as well.
Thanks for sharing, truly appreciate it!
I love your channel. Thank you for making this information more accessible to all.
SO MUCH KNOWLEDGE
YAAAAAAAAAAAYYYYYYY
Nawlidge
Anti- sway/ anti - roll bars provide a means to control weight distribution and mitigate "body roll" around the sides, front and rear of vehicle particularly when cornering thereby maintaining stability and contact with the road.
Great explanation! I wanted to learn about this component and this video was straight and to the point without being any longer than it needed to be.
Thank you
Basically you're making it act more and more like a live axle, the stronger the link between the two tires.
While it does add a linkage between the wheels at one end, an ARB is the *opposite* of a solid axle. A solid axle causes cross-side jacking on compression, magnified by the inboard position of the spring perches. An ARB causes cross-side compression, along with a reduction of body roll.
Clear explanation, as is usual on this channel.
Continued:
If you get added grip from increasing total roll stiffness (without changing tlltd) it will be due to minimizing the movement of poor suspension geometry. More likely though, you will lose grip due to minimizing the movement of *good* suspension geometry, and you will be much more likely to lose grip driving over a bump in the road as you've taken your independent suspension and then linked it up again (assuming you used a ARB to increase roll stiffness) left to right.
Thank you for explaining this so clearly. Also, what a trip seeing you ten years ago, well done sir love your channel and that whiteboard.
Beautiful, intelligent and quick lesson. Thank you my brother
I like your older vids better than the new ones
ty so much man , i am a fast virtual pilot , but i am terrible and setup , i just test and test ,but normaly i dont know what to do ,This helps a lot to know what i must to change .
I really enjoyed your videos and you looked so young in this video (not saying you are not anymore!) Thank you and great work.
Another great explanation.
Good to see some real-world examples in the video, too!
Well yes in a way, if you have too much camber, the tire wear will not be even, the inside part of the tire will wear faster and more than the outside.
Adjustable camber kit could solve this problem.
Another (cheaper) way is to compensate with adjusting your "toe", this will only minimize the tire wear, but the tire will still wear more on the inside than on the outside.
What car model are we talking about ?
Quick question: Wouldn't an ARB defeat the purpose of independent suspension? One consequence of installing an ARB is that what happens to one wheel will happen to the other and thus a suspension system such as a double wishbone isn't truly independent. Am I thinking about this the wrong way?
Thanks for the awesome videos by the way! I've learned more from you videos than from talking with all my wrench head buddies.
Good explanation, but I think your diagram would have made more sense if you'd shown that the anti-roll bar is clamped along its main length in order to only allow it to rotate.
Exactly. And most people forget to point this out in their videos
Dear Jason, thank You very much for explaining anti-roll (balancing) bar! I was watching every your video from 2017 onward, but this one dates back to 2012. You look like a kid here, what a discovery :D
They can be on both, and commonly are.
I removed my front arb in my Seat Leon Cupra R as it understeers from oem setup. I also got a larger rear arb and the chassis has a MUCH more neutral balance in the corners. Still a little push but that's more down to how the Haldex engages the rear tires.
+oistein74 nice job. on FWD racecars the front arb is often disconnected for racing on a wet track. This limits understeer and maximises traction.
My car is AWD and I still run with no front arb. Much much better.
Tal vez un dia, puedemos esperar. Queres hacer este reto? (Lo siento, ha pasado mucho tiempo desde que he hablado/escribido espanol).
Seeing the actual thing visually... Rather then diagrams will always be king.
Search my channel for "solid axle suspension," should clear things up! But no, I can't see a reason why you would use both.
Great video! It's quick, direct, simples, and highly informative. Well done!