Why is the steering so numb?
12-25-2007, 07:55 PM
#23
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Originally Posted by RED MX5,Dec 25 2007, 08:15 PM
I'm glad you admitted that you made that up
[QUOTE=RACER]moving the steering knuckles farther forward will make the steering heavier, hense more road feel.
[QUOTE=RED MX5,Dec 25 2007, 08:15 PM]That would work too, unlike the caster suggestions.
12-25-2007, 07:59 PM
#24
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Caster
The caster angle identifies the forward or backward slope of a line drawn through the upper and lower steering pivot points when viewed directly from the side of the vehicle. Caster is expressed in degrees and is measured by comparing a line running through the steering system's upper and lower pivot points (typically the upper and lower ball joints of an A-arm or wishbone suspension design, or the lower ball joint and the strut tower mount of a McPherson strut design) to a line drawn perpendicular to the ground. Caster is said to be positive if the line slopes towards the rear of the vehicle at the top, and negative if the line slopes towards the front.
A very visual example of positive caster is a motorcycle's front steering forks. The forks point forward at the bottom and slope backward at the top. This rearward slope causes the front tire to remain stable when riding straight ahead and tilt towards the inside of the corner when turned.
Caster angle settings allow the vehicle manufacturer to balance steering effort, high speed stability and front end cornering effectiveness.
Increasing the amount of positive caster will increase steering effort and straight line tracking, as well as improve high speed stability and cornering effectiveness. Positive caster also increases tire lean when cornering (almost like having more negative camber) as the steering angle is increased.
What's the downside to positive caster? If the vehicle doesn't have power steering, a noticeable increase in steering effort will be felt as positive caster is increased. Other than that, the effects of positive caster are pretty much "positive," especially increasing the lean of the tire when the vehicle is cornering while returning it to a more upright position when driving straight ahead.
12-25-2007, 08:43 PM
#25
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Originally Posted by RACER,Dec 25 2007, 11:55 PM
It can be done at an alignment shop, as caster is adjustable in the S2000.
Laters
[/QUOTE]My mistake. I though when you said steering knuckles that you were talking about lengthening the steering arms to quicken the ratio. Caster will make the steering heavier, but won't improve feedback of bumps and such very much at all.
12-25-2007, 08:49 PM
#26
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Originally Posted by RACER,Dec 25 2007, 11:59 PM
Caster
The caster angle identifies the forward or backward slope of a line drawn through the upper and lower steering pivot points when viewed directly from the side of the vehicle. Caster is expressed in degrees and is measured by comparing a line running through the steering system's upper and lower pivot points (typically the upper and lower ball joints of an A-arm or wishbone suspension design, or the lower ball joint and the strut tower mount of a McPherson strut design) to a line drawn perpendicular to the ground. Caster is said to be positive if the line slopes towards the rear of the vehicle at the top, and negative if the line slopes towards the front.
A very visual example of positive caster is a motorcycle's front steering forks. The forks point forward at the bottom and slope backward at the top. This rearward slope causes the front tire to remain stable when riding straight ahead and tilt towards the inside of the corner when turned.
Caster angle settings allow the vehicle manufacturer to balance steering effort, high speed stability and front end cornering effectiveness.
Increasing the amount of positive caster will increase steering effort and straight line tracking, as well as improve high speed stability and cornering effectiveness. Positive caster also increases tire lean when cornering (almost like having more negative camber) as the steering angle is increased.
What's the downside to positive caster? If the vehicle doesn't have power steering, a noticeable increase in steering effort will be felt as positive caster is increased. Other than that, the effects of positive caster are pretty much "positive," especially increasing the lean of the tire when the vehicle is cornering while returning it to a more upright position when driving straight ahead.
The caster angle identifies the forward or backward slope of a line drawn through the upper and lower steering pivot points when viewed directly from the side of the vehicle. Caster is expressed in degrees and is measured by comparing a line running through the steering system's upper and lower pivot points (typically the upper and lower ball joints of an A-arm or wishbone suspension design, or the lower ball joint and the strut tower mount of a McPherson strut design) to a line drawn perpendicular to the ground. Caster is said to be positive if the line slopes towards the rear of the vehicle at the top, and negative if the line slopes towards the front.
A very visual example of positive caster is a motorcycle's front steering forks. The forks point forward at the bottom and slope backward at the top. This rearward slope causes the front tire to remain stable when riding straight ahead and tilt towards the inside of the corner when turned.
Caster angle settings allow the vehicle manufacturer to balance steering effort, high speed stability and front end cornering effectiveness.
Increasing the amount of positive caster will increase steering effort and straight line tracking, as well as improve high speed stability and cornering effectiveness. Positive caster also increases tire lean when cornering (almost like having more negative camber) as the steering angle is increased.
What's the downside to positive caster? If the vehicle doesn't have power steering, a noticeable increase in steering effort will be felt as positive caster is increased. Other than that, the effects of positive caster are pretty much "positive," especially increasing the lean of the tire when the vehicle is cornering while returning it to a more upright position when driving straight ahead.
The simplest example is casters on furniture.
Making the steering ratio quicker WILL improve feedback, becuase of the reduced "gearing."
What the heck to you call the points where the rack attaches to the spindles?
(Old age, CRS syndrome.
)EDIT: I hate to admit this in public, but when it comes to terminology involving thinngs I don't deal with every day (steering knuckles and ackerman come to mind right off the bat
), I totally suck at terminology. At home I have cheet sheets to keep my ducks in a row, but we're on the road now and my cheat sheets are at home. 
12-25-2007, 09:01 PM
#27
When the steering wheel is too light adding caster will add resistence and therefore give you more steering feel. As someone else said, it also adds more camber the greater the turn angle and give quicker/easier recovery in a tail out situation.
Adding caster does NOT make the steering feel numb, the greater resistence allows you to feel the road more than when you had a too light feel and simply skated over the road changes.
Tires are what I find makes the most difference in steering feel. Some tires just seem to float over the road and also tend to give just as much grip as if they are floating.
As far as the racer counting pebbles in the road feel, I say no thank you on my street car. I like the S just as it is.
Adding caster does NOT make the steering feel numb, the greater resistence allows you to feel the road more than when you had a too light feel and simply skated over the road changes.
Tires are what I find makes the most difference in steering feel. Some tires just seem to float over the road and also tend to give just as much grip as if they are floating.
As far as the racer counting pebbles in the road feel, I say no thank you on my street car. I like the S just as it is.
12-25-2007, 09:58 PM
#28
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Originally Posted by Wildncrazy,Dec 26 2007, 01:01 AM
When the steering wheel is too light adding caster will add resistence and therefore give you more steering feel. As someone else said, it also adds more camber the greater the turn angle and give quicker/easier recovery in a tail out situation.
Adding caster does NOT make the steering feel numb, the greater resistence allows you to feel the road more than when you had a too light feel and simply skated over the road changes.
Tires are what I find makes the most difference in steering feel. Some tires just seem to float over the road and also tend to give just as much grip as if they are floating.
As far as the racer counting pebbles in the road feel, I say no thank you on my street car. I like the S just as it is.
Adding caster does NOT make the steering feel numb, the greater resistence allows you to feel the road more than when you had a too light feel and simply skated over the road changes.
Tires are what I find makes the most difference in steering feel. Some tires just seem to float over the road and also tend to give just as much grip as if they are floating.
As far as the racer counting pebbles in the road feel, I say no thank you on my street car. I like the S just as it is.
How can that not make the steering less sensitive to perturbations?
Please explain.
I agree that tires make the biggest difference on a given car, but cars vary as much or more than tires. Put S03's on an S2000 and on an R-32 Skyline GTR and compare. The S2000 will have MUCH greater feedback, even though the tires are the same.
12-25-2007, 10:00 PM
#29
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Hate to disappoint but castor has little to do with steering feel and everything to do with camber changes when you turn the wheels. The best way to picture the effect of castor on camber is to compare a sport-bike and a stretched out chopper. In motorcycles it's called rake. Positive castor is like a chopper. When you turn the front wheel it pitches over dramatically (negative camber). On a sport bike the effect is far less dramatic, it has less castor. Negative castor is damn near uncontrollable. The second you turned the wheel you would fly off.
The same applies to cars. The more castor you can apply the more negative camber you get on the outside wheels and the more positive camber you get on the inside wheels. If you have no castor then you would have no camber change when you turned the wheel. It would be the equivalent of a bike who's front forks were perpendicular to the ground.
Sticking with that image, what would happen if you were riding that bike at speed and you turned the handle bars 20
The same applies to cars. The more castor you can apply the more negative camber you get on the outside wheels and the more positive camber you get on the inside wheels. If you have no castor then you would have no camber change when you turned the wheel. It would be the equivalent of a bike who's front forks were perpendicular to the ground.
Sticking with that image, what would happen if you were riding that bike at speed and you turned the handle bars 20
12-25-2007, 10:02 PM
#30
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Originally Posted by cthree,Dec 26 2007, 02:00 AM
Hate to disappoint but caster has little to do with steering feel and everything to do with camber changes when you turn the wheels.