To be totally honest I cannot believe how long it took me to find this video. Literally weeks. What a great video explaining why Caster is important and what it does to your suspension while steering. I can't believe this video doesn't have more views. Thanks for the awesome video.
Thanks. Basically, when the wheel rotates and leans inwards to the turn there is more friction on the part of the wheel which is now leaning in to the turn and touching the ground. This friction causes the wheel to want to find the path of least resistance and lift the part of the wheel that is leaning in and touching the ground off of the ground. This causes the wheel to straighten and lift the leaning-in part of the wheel off of the ground. Makes sense! Thanks!
Ok...but what about drifting ? There the wheels want to countersteer on their own into the skid as a path of travel...but that means they are leaning more and more to do that. But drifters want to always have as much caster angle as possible.
Finally a video that tries to explain the importance of mechanical trail for the steering feel and self centering (how strongly the wheels want to turn into the direction of travel). In many videos about suspension geometry, they try to explain the effect of the caster angle by using for example office chairs with swivel caster wheels. But they fail to notice that swivel caster wheels actually have zero caster angle (the steering axis is vertical), but plenty of mechanical trail (how much the steering axis ground intersection point is forward of the tyres contact patch center). It is the mechanical trail that gives majority of the steering feel and self centering. The more you have mechanical trail, the more you will get steering feel. Caster angle (and KPI angle) by itself gives only very little steering feel and self centering (it gives some, because it tries to lift the tyre onto its edge but the effect is very small when compared to mechanical trail). I think that the confusion between the effects of caster angle and mechanical trail comes from the fact that in majority of automobile suspensions, changing one setting also changes the other. It is possible to build suspension where caster angle and mechanical trail can be changed independently. Caster angles main use is to get better camber angles during cornering. The effect of mechanical trail can most easily be seen by playing around with shopping trolleys or office chairs. I think it would be less confusing to use the whole term caster angle, when talking about suspension caster angles to separate it from caster wheels. I would actually like to know why those caster wheels are called caster wheels even through they have zero caster angle? Is it the name of some old manufacturer (like hoover for vacuum cleaners) or is it derived from some old english or some other languages term or saying.
At 2:38 you meant to say camber and said caster, right? Not being a douche, just trying to learn about it and got confused there. Maybe you can add some note via youtube to change that, if I got it right. Thanks again for these videos. I'm happy I've found your channel today =]
Are OEM caster specs the actual measurement at +/- 20 deg steering angle (i.e. lock to lock) or are they the true castor angle which the measurement must be converted to - i.e. measured angle / sin(20) ?
Hello I just wanted to ask lets say one wheel has positive caster and other wheel has negative caster what issues could occur?. Does this situation can cause vehicle pulls to one side or just tire wear at various points?
so if you had negative caster, or a situation where the 'moment arm' was behind the 'point of contact' (instead of in front like your example) of the wheel you could have a dangerous situation? going around a corner the car would want to turn more and more. Are there any examples of negative caster being used or usefull?
+Steven Olson That is true, if the contact patch force was ahead of the moment arm you would have unstable steering, which is not a good idea. I honestly can't think of any reason why you would want that scenario, although maybe there is something obscure like rock crawlers or heavy machinery where perhaps they have to do it for structural reasons?
Do you still have the FT86? I'm weighing suspension upgrade options and want to improve front end grip and overall steering feel. The stock tires and suspension understeer pretty badly in tight corners off the brakes. I'm wondering if adjustable pillowball mounts and other minor upgrades would help a lot or if I should just save up for a complete package to fine tune all of the settings. I know the stock tires are a huge part of the problem.
For 250,000 miles I've been trying to figure out why my trucks steering doesn't return properly! Replaced every part on the front end multiple times brought it to multiple alignment shops no one can tell me why. Doing my own research I've come down to the conclusion that something is off with my caster the vehicle pulls to the right and sterring feels lighter when I turn right but doesn't have good feedback. When you steer to the left feels heavier but to me has better Road feel. The question I have is since it's steering easier to the right and heavier to the left do I take Caster out of the right hand side or do I add Caster to the left hand side since the steering doesn't return correctly, I was thinking adding Caster to the left hand side would make both sides lighter therefore correcting or helping my non return steering Oh ya old girl has 370,000 on her and has had this issue since I bought the truck with 100 000 MI I bought it with stock upper A arms had this issue then! I installed cognito upper a arms still has the issue. I did turn torsion keys in, t A arms allow me to bolt ball joints in on top or bottom to fix camber issue from Turning in bolts on cam keys and raising the truck a little
G'day mate, great stuff. One nomenclature question: What did you mean by pickup point? Would you be able to tell me as the name of the part? I.E Steering knuckle, Lower Balljoint, etc. Cheers.
My car has a caster difference of 1.10° (L=4.6° and R=3.5°). I'm suspecting a bent frame. How do I check if the cause for the caster inequality really is a bent frame? Also, if my frame really is bent, is there a way I can fix it?
@@ydaleeks3726 The only way I know how is to use camber plates that also allow caster adjustment. But that's not fixing the problem at the root cause though.
so here’s the thing idek if anyone will answer this but let’s say i’m going fast on a kart and i hit a bump i don’t want to lose control bc of how finicky my steering is what do i do ab that
Interesting, very interesting .... So you are saying there is no real drawbacks to increase caster, until you reach point of too much negative camber during cornering and/or lost steering feel? Since you can then adjust for smaller static camber, the only potential drawback is lost steering feel with very high caster angle? (Assuming kingpin inclination is good)
Yes, its based upon how you make your suspension geometry. For ex if you put increased jacking in the side view, which everyone calls ANTI-geometry, that way you change the relative side view angle between the upper and lower wishbone in a SLA setup and so you create different paths for the outer ball joints. So, as the wheel will go in bump or rebound, the caster will change as a function of the amount of ANTI given.
Vehicles have a minimum and maximum and preferred caster and camber spec. To do a alignment the vehicle should be Aligned with the weight it will be carrying on a normal day of use..because weight will change the alignment ..vehicle alignment can be within the manufacturers specifications sitting on a alignment rack ..then when you put people ,fuel,etc. in the vehicle it will not handle the way it should.
Keshava Siva For my car (BMW E46 - front suspension = MacPherson Struts), you can use a camber+caster plate to tilt the upper shock mount. Also, you could use offset front lower control arm bushings to modify the way the front lower control arm sits, but you could also go for a custom heim joint front lower control arm bushing lollipop to add even more caster than offset bushings can.
You make several assumtions. The first being that all cars have strut suspensions. The second that caster is only important in cornering. How does caster affect straight line handling ? What is the effect negative caster vs positive caster ? You need to visit more websites and draw less..
To say the caster winds "on" or "off" camber is a bit misleading. In a right turn positive caster will increase (or make more +'ve) the camber of the right front, but decrease (make more -'ve) the camber of the left front. Any caster that is non-0 will cause a change in the magnitude of the camber as the wheel is turned.
NO, what i mean is static camber is 10 degrees, positive caster will decrease this number in the corner. winding off. if caster is negative the camber will increase with steering angle. which no one ever does. because its unstable
I do not see any way to determine a "best video" on a channel like this. It addresses a question and answers the question. It is meant purely for informational and educational purposes. It is not meant to entertain you, it is purely functional, that being to explain caster. None of his other videos fulfill that same function. If he had a second video that also explained caster, and that video explained it better, then yes, the comparison could be made there. As it is, you may as well say a certain kind of apple is not the best apple, because oranges exist.
Forget the castor angle, more importantly, in the diagram he has the front of the car on the right. This messes with right handed people's heads. This should be illegal!
Explaining this kind of things with words only is lame. Please add some animation for more clarity. The way I try to conceptualize caster is by comparison with a bike's rake-trail-offset combination.
To be totally honest I cannot believe how long it took me to find this video. Literally weeks. What a great video explaining why Caster is important and what it does to your suspension while steering. I can't believe this video doesn't have more views. Thanks for the awesome video.
Its the best one
What is the difference between this and regular sugar?
Daniel Luong tsk 🤣
Thanks. Basically, when the wheel rotates and leans inwards to the turn there is more friction on the part of the wheel which is now leaning in to the turn and touching the ground. This friction causes the wheel to want to find the path of least resistance and lift the part of the wheel that is leaning in and touching the ground off of the ground. This causes the wheel to straighten and lift the leaning-in part of the wheel off of the ground. Makes sense! Thanks!
Andrew Nash thank you, the way you worded that helped me understand it much better
Ok...but what about drifting ? There the wheels want to countersteer on their own into the skid as a path of travel...but that means they are leaning more and more to do that. But drifters want to always have as much caster angle as possible.
Finally a video that tries to explain the importance of mechanical trail for the steering feel and self centering (how strongly the wheels want to turn into the direction of travel).
In many videos about suspension geometry, they try to explain the effect of the caster angle by using for example office chairs with swivel caster wheels. But they fail to notice that swivel caster wheels actually have zero caster angle (the steering axis is vertical), but plenty of mechanical trail (how much the steering axis ground intersection point is forward of the tyres contact patch center).
It is the mechanical trail that gives majority of the steering feel and self centering. The more you have mechanical trail, the more you will get steering feel. Caster angle (and KPI angle) by itself gives only very little steering feel and self centering (it gives some, because it tries to lift the tyre onto its edge but the effect is very small when compared to mechanical trail). I think that the confusion between the effects of caster angle and mechanical trail comes from the fact that in majority of automobile suspensions, changing one setting also changes the other. It is possible to build suspension where caster angle and mechanical trail can be changed independently. Caster angles main use is to get better camber angles during cornering.
The effect of mechanical trail can most easily be seen by playing around with shopping trolleys or office chairs.
I think it would be less confusing to use the whole term caster angle, when talking about suspension caster angles to separate it from caster wheels. I would actually like to know why those caster wheels are called caster wheels even through they have zero caster angle? Is it the name of some old manufacturer (like hoover for vacuum cleaners) or is it derived from some old english or some other languages term or saying.
That's exatcly what i was going to write a comment about.
They use chair wheels to demonstrate that the wheel contact is behind the pivot point. Camber on the other hand does not exist with arm chairs...
Does too much positive caster "tightens" your steering while too much negative caster "loosens" your steering? If yes, then why?
Caster made easy!! Thanks for the info.
Would you like an explanation of front end geometry? I think that would help a lot.
Best video on this topic
At 2:38 you meant to say camber and said caster, right? Not being a douche, just trying to learn about it and got confused there. Maybe you can add some note via youtube to change that, if I got it right. Thanks again for these videos. I'm happy I've found your channel today =]
Are OEM caster specs the actual measurement at +/- 20 deg steering angle (i.e. lock to lock) or are they the true castor angle which the measurement must be converted to - i.e. measured angle / sin(20) ?
Hello I just wanted to ask lets say one wheel has positive caster and other wheel has negative caster what issues could occur?. Does this situation can cause vehicle pulls to one side or just tire wear at various points?
For rear caster and front caster, you don't change those for track alignment right? They stay the same for street and track alignment? (c7)
That was a great take.
Very smooth delivery and quick illustrations.
🤜🏼🤛🏼🇦🇺🐇🍀🍀🍀😎🤓
so if you had negative caster, or a situation where the 'moment arm' was behind the 'point of contact' (instead of in front like your example) of the wheel you could have a dangerous situation? going around a corner the car would want to turn more and more. Are there any examples of negative caster being used or usefull?
+Steven Olson Shopping trolleys. Good for mad drifts down the dairy aisle.
+Steven Olson That is true, if the contact patch force was ahead of the moment arm you would have unstable steering, which is not a good idea. I honestly can't think of any reason why you would want that scenario, although maybe there is something obscure like rock crawlers or heavy machinery where perhaps they have to do it for structural reasons?
Can you add website's link in the descripsion? (website you mention in the beginning)
Do you still have the FT86? I'm weighing suspension upgrade options and want to improve front end grip and overall steering feel. The stock tires and suspension understeer pretty badly in tight corners off the brakes. I'm wondering if adjustable pillowball mounts and other minor upgrades would help a lot or if I should just save up for a complete package to fine tune all of the settings. I know the stock tires are a huge part of the problem.
For 250,000 miles I've been trying to figure out why my trucks steering doesn't return properly! Replaced every part on the front end multiple times brought it to multiple alignment shops no one can tell me why.
Doing my own research I've come down to the conclusion that something is off with my caster the vehicle pulls to the right and sterring feels lighter when I turn right but doesn't have good feedback. When you steer to the left feels heavier but to me has better Road feel.
The question I have is since it's steering easier to the right and heavier to the left do I take Caster out of the right hand side or do I add Caster to the left hand side since the steering doesn't return correctly, I was thinking adding Caster to the left hand side would make both sides lighter therefore correcting or helping my non return steering
Oh ya old girl has 370,000 on her and has had this issue since I bought the truck with 100 000 MI
I bought it with stock upper A arms had this issue then! I installed cognito upper a arms still has the issue. I did turn torsion keys in, t A arms allow me to bolt ball joints in on top or bottom to fix camber issue from Turning in bolts on cam keys and raising the truck a little
He didn't mention the most important result of caster, which is trail, which you need for the car to go in a straight line and not just wander off
Watch it again starting at 3:11. It is there.
How identify may car caster angle is out??
Can u please make a video on how steering setup should be made for drifting..
G'day mate, great stuff.
One nomenclature question:
What did you mean by pickup point?
Would you be able to tell me as the name of the part?
I.E Steering knuckle, Lower Balljoint, etc.
Cheers.
My car has a caster difference of 1.10° (L=4.6° and R=3.5°).
I'm suspecting a bent frame.
How do I check if the cause for the caster inequality really is a bent frame? Also, if my frame really is bent, is there a way I can fix it?
My brand new car came with caster difference I think somebody who transported the car hit it really bad. I am here now to know is its fixable.
@@ydaleeks3726 The only way I know how is to use camber plates that also allow caster adjustment. But that's not fixing the problem at the root cause though.
so here’s the thing idek if anyone will answer this but let’s say i’m going fast on a kart and i hit a bump i don’t want to lose control bc of how finicky my steering is what do i do ab that
Interesting, very interesting .... So you are saying there is no real drawbacks to increase caster, until you reach point of too much negative camber during cornering and/or lost steering feel?
Since you can then adjust for smaller static camber, the only potential drawback is lost steering feel with very high caster angle? (Assuming kingpin inclination is good)
Can caster change when a vehicle is moving ??
Yes, its based upon how you make your suspension geometry.
For ex if you put increased jacking in the side view, which everyone calls ANTI-geometry, that way you change the relative side view angle between the upper and lower wishbone in a SLA setup and so you create different paths for the outer ball joints. So, as the wheel will go in bump or rebound, the caster will change as a function of the amount of ANTI given.
I thought caster was a ghost... Just kidding. Great video!
+R Theory Motorsports LTD I thought it was a type of sugar ;) Thanks for your support!
Wtf.. it’s oil actually. 😅
is there negative caster in real coz it seems quite inappropriate and impossible
EARLY Z28
Vehicles have a minimum and maximum and preferred caster and camber spec. To do a alignment the vehicle should be Aligned with the weight it will be carrying on a normal day of use..because weight will change the alignment ..vehicle alignment can be within the manufacturers specifications sitting on a alignment rack ..then when you put people ,fuel,etc. in the vehicle it will not handle the way it should.
How increase the caster angle, please reply if you know
Keshava Siva
For my car (BMW E46 - front suspension = MacPherson Struts), you can use a camber+caster plate to tilt the upper shock mount. Also, you could use offset front lower control arm bushings to modify the way the front lower control arm sits, but you could also go for a custom heim joint front lower control arm bushing lollipop to add even more caster than offset bushings can.
How do you fix cross caster and caster please on 2013 300
You make several assumtions. The first being that all cars have strut suspensions. The second that caster is only important in cornering. How does caster affect straight line handling ? What is the effect negative caster vs positive caster ? You need to visit more websites and draw less..
Thank you!
Positive Caster winds OFF camber with steering angle.
To say the caster winds "on" or "off" camber is a bit misleading. In a right turn positive caster will increase (or make more +'ve) the camber of the right front, but decrease (make more -'ve) the camber of the left front.
Any caster that is non-0 will cause a change in the magnitude of the camber as the wheel is turned.
NO, what i mean is static camber is 10 degrees, positive caster will decrease this number in the corner. winding off. if caster is negative the camber will increase with steering angle. which no one ever does. because its unstable
@@dethkon2284 I think it is the way you said but vice-versa 🤔
You stoned 👀🔥🔥
Be careful not confuse caster with Ackerman angle
I thought im gonna learn how caster makes music but turns out its physics
Ffs but this was interesting
Not bad, but not his best video by far.
I do not see any way to determine a "best video" on a channel like this. It addresses a question and answers the question. It is meant purely for informational and educational purposes. It is not meant to entertain you, it is purely functional, that being to explain caster. None of his other videos fulfill that same function. If he had a second video that also explained caster, and that video explained it better, then yes, the comparison could be made there.
As it is, you may as well say a certain kind of apple is not the best apple, because oranges exist.
Forget the castor angle, more importantly, in the diagram he has the front of the car on the right. This messes with right handed people's heads. This should be illegal!
Explaining this kind of things with words only is lame. Please add some animation for more clarity.
The way I try to conceptualize caster is by comparison with a bike's rake-trail-offset combination.