[Nikhilb2008]

What is Wheel Alignment? In most cases, this is the adjustment of the tie-rod end which takes care of Toe.

Most modern wheel aligners(either 3D or the sensor type) have a computer running either Windows or Linux as part of the system. The computer will be running the software which is proprietary. So, a Hunter wheel aligner will have either a WinAlign(windows) or a ProAlign(Linux and cheaper).

So, the technician before starting his job opens the software, accesses the database stored in the system and selects the car. In your case, it will be a Honda Civic 2007---

The last part is left blank which means 2007- current. He then enters some other data like Odometer reading, Vehicle Reg no, etc....

Once he does this, the system displays the specifications for the particular car. It will show one value as the accurate value and next to it will be the tolerance. It will be in the range of a few minutes.

The readings are all in degrees and minutes.

Then the technician has to follow a set procedure which varies from machine to machine. He rols the car forward and backward, then rotates the steering from one side to another. After this, the system displays the MEASURED values.

If you have driven your car over some really bad roads or had a suspension overhaul, then the measured values will vary substantially from the required specs.

The technician then goes below the car to adjust the various angles.

Now, Alignment has three main measurements.

Toe:The car could have toe-in or toe-out. Toe in is when the two front tyres of the car are facing inwards. Imagine standing straight and looking at your feet. The ideal position is for your feet to be parallel(same with cars... the tyres have to be parallel). Now, twist your feet so that your toes point inwards. This is TOE-IN.

Toe-Out is similar, but as the name says, the two front tyres both point outside. Away from the centre of the car.

Now, Toe can have a drastic effect on car handling, steering position and tyre wear. As you can imagine, when the tyres arent parallel, there is minor scrubbing and so, the insides of the front tyres get worn out much faster. And an experienced or knowledgeable eye will see that it isnt normal wear but scrubbed.





This toe can be easily corrected by an experienced technician. The important thing is to get an accurate reading before and after the alignment. Also, you need to know the correct specifications.


Camber: This is the tilting of the top of the tyre seen from the front. It could tilt inwards or outwards.

If it tilts inwards as seen from the front, then the car is said to have negative camber. If it tilts outwards, it has positive camber.

This could lead to pulling, steering not being straight and uneven tyre wear. Let's take the case of Negative Camber. The load on the inside of the tyre is more and hence that side of the tyre wears out more. This type of wear is different from the wear you get from Toe-in. If it is wear due to camber, the inside of the tyre shows smooth wear. It's more than the rest of the tyre, but you can see that the tyre hasnt scrubbed.




Camber is not easily adjusted usually. Will explain more later in the post.


Caster: This is the angle made by the steering column with respect to the centre line of the tyre when seen from the side.

It sounds a bit complicated, but this image should make it clear.




Almost all cars have positive caster. Caster is responsible for making the steering go back to the centre position when you are accelerating out of a turn.

Look at even a bicycle. It also has positive caster.

Too much positive caster will result in the steering coming back to the centre position very fast. This isnt necessarily better. Every car is designed with a particular caster angle in mind. No outside person should tinker around with this unless they know EXACTLY what they are doing.


Now, let's look at the real situation.

The Honda Civic comes with ONLY adjustable TOE settings and that too only for the front suspension(I MIGHT be wrong! It's difficult to remember data for so many cars!).

If you need to adjust the Camber or Caster, it isnt impossible, but is much more tedious. A normal alignment job(depending on the type of equipment used) can take between 15-45 minutes. If you need to adjust camber or caster for a car which doesnt have adjustable settings, it could take upwards of 2 hours!

What the technician does is to dismantle the entire suspension and then work on it.

That is why it is recommended that you get camber and caster rectified ONLY at an authorised service centre or a technician you trust.

Originally Posted by laluks

I have asked the service advisor what do they do in wheel alignment. In the conversation he said the camber/caster is fixed during production and it never changes. Is he bluffing??

Next - I see that during wheel balancing at a good year outlet they used some weights which was not looking the same as what was there as before. I had flat aluminium coloured ones before, and this one is the normal black coloured lead cylinders! I see that above 150kmph vibrations come in - so the balancing is not perfect?

Now, coming to this post... Camber and caster CAN change over a period of time. Afterall, dont underestimate our Indian roads!

The Wheel balancing part has a simple explanation. The Honda people might have used sticker weights. These are flat and usually go on the inside of the wheel so that they are not visible from the outside. This is dont ONLY for visual effect. There are certain clip-on weights that come for alloys and you can use these as well, but it is pointless. The cost difference(if any) is marginal. A few paise per gram but these also clip on to the outside of the rim and look ugly.

It is always recommended you go in for Sticker weights. These come with a very strong adhesive which stick very well to the wheel. The point of application has to be cleaned thoroughly by the guy balancing the wheel before he sticks the weight.

If any of you are supervising the balancing, make sure they clean that spot thoroughly. If your rim is quite dirty, then ask him to wipe that spot with a wet cloth(dont use some soap or detergent, that could corrode the aluminium) and then stick the weight.

This ugly looking weight that has been put on your wheel might look bad, but just because they have used a different type of weight doesnt mean that is the cause for the wobbling. Wobbling could be simply due to the fact that the guy doing the balancing hasnt put the correct weight or maybe he has put it at the wrong spot. Or maybe another piece on the other side of the wheel has fallen off and has caused the imbalance.

Guys, keep one thing in mind. Many tyre shops, service centres, mechanics, etc.. dont use new weights. They use old weights and put them on your car. They say they are doing it free, but there is a reason it is free.

Usually it is the clip-on weights that are re-used. The problem with this is that the clamp which holds the weight to the rim loses it's strength once it is removed from the rim using a particular tool. So, when someone re-uses it, the strength is very much reduced and it may not remain on the wheel for long. It could fall off at high speed which means you end up with an unbalanced wheel.

PS: I know that by this time Laluks would have long got his balancing problem sorted out, but just giving some info.

Originally Posted by swageo

Yes, this is true. Onle toe can be adjusted. This is what XL Tyre point guy told me, though I was not fully convinced.

Well, I hope my above post convinces you! At the very max, rear toe can be rectified as well. (I will confirm about the civic tomorrow and get back to you.).

There are some cars that come with a lot of adjustable settings.

The Mitusbishi Lancer (old one) came with front toe and camber and rear toe and camber!

Many older Mercs came with front and rear toe.

Like this, each car is different. However, 99% of the cars in India have only adjustable front toe.

Originally Posted by sandeep108

Apparently the rear alignment seems more critical. Maybe some technical gurus will be able to throw more light on the civic's tire alignment features, tips.

Rear alignment is less critical as steering is always done with the front wheels. Rear alignment is very rare in most cars. Even in the cars which have rear alignment, in most cases it is only TOE that can be adjusted.

Originally Posted by swageo

I don't see anyone attempting the rear wheel alignment. In past, they atleast used to mount the sensor on rear wheels, but thats not happening now. Once I questioned this, and they said, "there is nothing to align" Hu..

Worst, after aligning steering got misaligned. After my repeated visit, finally XL tyre guy "fixed" it. Good only knows what alignment the front wheel has now.

Rear wheel alignment doesnt have much to dowith mounting the sensors on the rear wheels.

A proper wheel alignment job means sensors should be mounted on ALL 4 tyres/wheels.

It's like this....

If you align ONLY the front two wheels without referring to the rear, then you could have a major problem. That is why all modern wheel aligners come with 4 wheel alignment.

4 wheel alignment is different from REAR wheel alignment.

This link explains it very well.

Wheel Alignment: What Everyone Should Know About Wheel Alignment, Why Four Wheel Alignment


So, you see, the front wheels HAVE to be measured with respect to the rear wheels. Otherwise, you will have a problem even if the machine says that alignment is perfect.

Another reason why many shops, service centres, etc in India offer PHHHRRRRRRREEEEEEEEEE Wheel alignment. They in all probability be using some ancient machine which will not do the measurement properly.


Actually, we have loads of videos regarding alignment and various implications of bad alignment. Unfortunately, they are all stored in our alignment system! It's difficult to extract it from there and upload it to youtube. I will try to do this sometime though. It would explain Wheel Alignment beautifully.


PS: Apologies for the lengthy post. But when you guys mentioned caster/camber, I thought it's better to explain before giving my answers.

[laluks]

Nikhil, thanks for the informative post.

[benbsb29]

Nikhil, that was a really informative post. Thanks a lot!
Lets see if we can get this put up somewhere where everyone can view it without having to search.

[Cyborg]

Nikhil, thank you very much for such a comprehensive and informative post.
Regards

[Nikhilb2008]

Thanks guys.

I will post a photo of a typical Alignment report here tomorrow.

[sdp1975]

Nikhil, when I got my GP aligned at Madhus about 2 weeks ago - the Model they had in the software database ( and in the report ) was "Fiat : Punto- :2000 1.2 (8V/16V)".

Mine is actually a Grande Punto - 1.3 MJD , so does this make a difference ?

Nice explanation above.

[Nikhilb2008]

I dont think so. This means the Punto sold in India has the same suspension settings as the Punto from 2000 onwards.

[vaisakhr]

I have a question.

What is the correct method for putting a front tyre with one side worn out?

One guy in the wheel alignment shop said the worn out should be on out side and not on inside. But I don't think that is correct, because as most of the cars are having +ve camber the outer side will be having more wear. So in that case if we set the tyre with more worn out side on outer it will even wear more and the cars straight motion will be affected. What is your opinion?

Originally Posted by sdp1975

Nikhil, when I got my GP aligned at Madhus about 2 weeks ago - the Model they had in the software database ( and in the report ) was "Fiat : Punto- :2000 1.2 (8V/16V)".

Mine is actually a Grande Punto - 1.3 MJD , so does this make a difference ?

Nice explanation above.

I there won't be any difference at all.

[SPIKE ARRESTOR]

@Nikhil can you explain how wheel alignment is done for vehicles with Leaf springs? is it using wedges? (please post pics on this if you have any), also how is wheel alignment done using a Camber bolt? i am attaching a photo of camber bolt for your reference.

Spike

Mods sorry for the bad picture quality.

[vaisakhr]

Originally Posted by SPIKE ARRESTOR

how is wheel alignment done using a Camber bolt?

Camber Bolt FAQ and Tutorial

[Nikhilb2008]

Originally Posted by vaisakhr

I have a question.

What is the correct method for putting a front tyre with one side worn out?

One guy in the wheel alignment shop said the worn out should be on out side and not on inside. But I don't think that is correct, because as most of the cars are having +ve camber the outer side will be having more wear. So in that case if we set the tyre with more worn out side on outer it will even wear more and the cars straight motion will be affected. What is your opinion?

Most cars actually have NEGATIVE camber. So, put the tyre with the worn out portion facing outside.

[vaisakhr]

Originally Posted by Nikhilb2008

Most cars actually have NEGATIVE camber. So, put the tyre with the worn out portion facing outside.

Are you sure about that? I think I noticed some +ve values during the wheel alignment.

[Nikhilb2008]

Yes. 100%.

Positive value could be caster or toe

[SPIKE ARRESTOR]

@Nikhil Most cars do not have negative camber, specially for indian conditions where roads are crowned always a positive camber is preferable. just for information which are those cars running on negative camber, please correct me, i may be wrong.

Spike

[Nikhilb2008]

Oops.... I was mistaken. All cars do have Positive camber. Not negative. However, Negative camber aids in handling. But Positive camber makes the steering easy to handle.

Most cars to be used in the city have positive camber. Only race cars I guess have minor negative camber. And that too not all race cars.