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Old 31st July 2006, 12:03   #16
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Thank you all,

I have reduced tyre pressure to 29 psi. I didn't get enough road to check whether this makes any difference

I am planning to do alignment in another couple of days. So keeping my fingers crossed.

I think we need to settle for slight toe-in, right? But how much?
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Old 31st July 2006, 12:41   #17
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Just get Wheel Balancing done that should solve this (everything else including alignment should be stock specifications).
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Old 31st July 2006, 12:55   #18
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Quote:
Originally Posted by 1100D
Just get Wheel Balancing done that should solve this (everything else including alignment should be stock specifications).

Hi,

Can you explain the logic of wheel balancing to solve this problem.

Viper
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Old 31st July 2006, 13:21   #19
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On a smooth surface at high speeds if you have a car trying to pull left-right (both directions), it has to be the wheels being unbalanced. Having separate rotational mass at both the front wheels and that mass oscillating back and forth between the suspension line would cause the forces to interact on the steering system. However when the car has a consistent pull to one side on a smooth surface its the alignment (generally toe-out on the side the car pulling, that side needs to be given a Toe-in).

On a rough surface the story is slightly different. Generally there would be some amount of pull on either side whenever the car hits a rough patch, but when the car shows more tendency to twitch out of line (more than the perceivved normal) on a rough patch thats when its the Toe-in adjust ment that needs to be made.

Also check if the front rims are bent at any point (this could cause imbalance in the wheels too)

Last edited by 1100D : 31st July 2006 at 13:24.
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Old 31st July 2006, 13:29   #20
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Quote:
Originally Posted by 1100D
On a smooth surface at high speeds if you have a car trying to pull left-right (both directions), it has to be the wheels being unbalanced. Having separate rotational mass at both the front wheels and that mass oscillating back and forth between the suspension line would cause the forces to interact on the steering system.
This would cause a vibration on the steering wheel

Quote:
Originally Posted by 1100D
However when the car has a consistent pull to one side on a smooth surface its the alignment (generally toe-out on the side the car pulling, that side needs to be given a Toe-in).
That is true but if it is only for one wheel.

Now what would happen if both the front wheels were toed out?
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Old 31st July 2006, 14:01   #21
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Quote:
Originally Posted by viper
Hi,

Can you explain the logic of wheel balancing to solve this problem.

Viper
When tread wear is "cupped," it means the tires are out of balance. However this can be felt by the driver in most cases at higher speeds. will make the ride a bit bouncy kind of.
Wheel alignment is primary thing for getting wheels to drive straight as India road conditions can get wheels to be left or right aligned after hitting pot holes, dividers and
the next to get done is balancing.
in any case it needs a professional touch, preferably an "easy" but technical job.
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Old 31st July 2006, 14:05   #22
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Quote:
Originally Posted by Psycho
This would cause a vibration on the steering wheel



That is true but if it is only for one wheel.

Now what would happen if both the front wheels were toed out?
do u need an answer for this!!!
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Old 31st July 2006, 14:13   #23
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Quote:
Originally Posted by Psycho
This would cause a vibration on the steering wheel



That is true but if it is only for one wheel.

Now what would happen if both the front wheels were toed out?

Yes logically speaking yes, but the frequencies from the unbalanced wheels usually add up to a lower frequency (higher amlitude) and there is a slight feeling of car pulling to the right and left in equal intervals (on the steering).

Why I am so sure is because I have faced this first hand, in US in my Accord. The previous day my car had hit an unexpected obstacle on the interstate, the next day I had this experience at over 60-65mph wherein the car was apearing to pull left and right slightly (as if there was some cross winds pushing the car and then changing direction at equal intervals, checked that the nearby trees were static meaning there was no crosswind at all) I got the front wheels balanced and it went away just after that.

Toe Out on both the wheels would mean the car would be very unsettled after hitting every pothole. Generally rally cars have a slight Toe-out setting enabling them to be nimble around corners.

Last edited by 1100D : 31st July 2006 at 14:14.
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Old 31st July 2006, 14:16   #24
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Quote:
Originally Posted by 1100D
Toe Out on both the wheels would mean the car would be very unsettled after hitting every pothole. Generally rally cars have a slight Toe-out setting enabling them to be nimble around corners.
That unsettled feeling can be called a floating steering as the car does not keep a straight line on a level road and does not pull in any direction, however it tends to follow the contours of the road.
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Old 31st July 2006, 14:21   #25
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Pardon my ignorance guys... i have never driven an esteem at high speeds but isnt this a problem with the car itself, the superlight build of the esteem, coupled with superlight steering... it weighs a mere 35 kg more than a Santro!
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Old 31st July 2006, 14:26   #26
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Quote:
Originally Posted by Psycho
That unsettled feeling can be called a floating steering as the car does not keep a straight line on a level road and does not pull in any direction, however it tends to follow the contours of the road.
On a level road the contours would be flat, so generally the car would track straight. Slight imperfection though would bother the car (in a toe-out setting).

But the flying feeling, as I mentioned, on a level road (one without surface imperfections) would mainly because of rotational masses within the confines of the car (i.e mostly the front wheels), which could be as a result of either or both of an imperfect rim or unbalanced wheel.

In anycase the cause that could throw the wheels off-balance or the rims-bent could also have unsettled the suspension geometry, so always advisable to check the alignment as well.

But for sure, no stock car (especially esteems) would give that flying feeling at such low-speeds unless there is severe problem with Wheel balancing (which could lead to alignment problems as well)
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Old 31st July 2006, 18:13   #27
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I own an Esteem and have never faced this kind of problem at 120KMPH or higher speeds. I keep tire pressure at 27psi. BTW recommended tire pressure by manufacturer is 26psi!!
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Old 31st July 2006, 18:37   #28
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29 psi? esteem tyre pressure is 26 psi right?
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Old 31st July 2006, 18:52   #29
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Guys it could also be because of more play in the steering arms also right?This would cause the steering to rotate a little freely at highspeeds which is not confidence inspiring and we get a feeling that the car is front light that time
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Old 1st August 2006, 11:14   #30
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Quote:
Originally Posted by extreme_torque
Pardon my ignorance guys... i have never driven an esteem at high speeds but isnt this a problem with the car itself, the superlight build of the esteem, coupled with superlight steering... it weighs a mere 35 kg more than a Santro!
You are pardoned !!

It is worth knowing that a F1 car weights around 600Kg-including the driver. Do I need to explain more?

Thank you all. Let me implement your suggestions and I shall get back with the results
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