Why you Cannot do a "Wheel Alignment" on the 6R polo

[gavs]

It's the same subject Gavs - just a different answer.

As I've said before, you can do an alignment if you're willing to work at it. I know you don't agree with me but even the manual says it can be done.

Not really, one is a question that you have answered several times and the purpose of the thread is to make a statement.

I've also never said you can't do an alignment, you cannot individually adjust camber by any meaningful amount which is what the generic action is when someone gets a "wheel alignment". The manual says this and I stand by it.

[rana_kirti]

He should set the wheel straight ahead & then adjusted the tie rods underneath.


I can't work out why you'd do this if the car had been fixed.

Subframe adjustment will do both angles but I'd guess they've done what they can. There's only so much movement available.

Don't worry about the caster reading - it's not a tyre wearing angle.


Why on earth would you get it fixed with one set of tyres & then fit another set? The alignment is to fine tune the chassis angles and also to compensate for any run out that the tyres might have.

What you've done is like having a misfire in an engine & getting it fixed & then puting another engine in and wondering why it's misfiring again.

They might have excessive run out but usually a L/R swap at the front will fix that. What brand are they? Are they directional or asymmetrical?

When they jack up the front where are they puting the jack?

Hey brad,

what does the above statement in bold mean ? The tyres are Hankook Ventus V8 RS 205 55 15.

OEM size were 185 65 15 Apollo Acellere. I went with Broader Hankooks for a more grippy ride with a more planted feel with the broader tyres and added weight to the steering.

thanks.

Edit: I have posted my experience with a Hunter Road Force GSP9700 in a separate post below.

[rana_kirti]

Hunter Road Force GSP 9700 experience....

hi brad and everyone...

i researched further on the internet about left pulling and came upon the term "radial pull". further research led me to read about the Hunter Road Force GSP9700. I found about a tyre shop in my city which has this equipment and made an appointment with him.

Over there the owner explained and showed me how the machine works and post all tyres psi to 32 psi took road force and lateral measurements of all the 4 tyres. and then he then stuck weights on the red line showed by laser.

next the machine made the wheels OK and then tagged all 4 wheels with Straight Trak Technology. It then showed various options on the screen as to installing which wheel where will result in how much total lateral pull in which direction. it had options of least pull and least vibrations and also alternate options to both.

i choose a option which resulted in 25 pull to the right. Now my tyres are directional and 205 55 15 Hankook V8 RS. So we had to undo 2 tyres from the rims and remount it inside out to keep it consistent with the rotation arrow. The 2 tyres were then re balanced after this.

I'm not sure if this affects the overall result as the 4 tag position chart was decided with the tyres being balanced in the other direction. so effectively 2 tyres were rebalanced after the deciding the 4 position chart because my tyres are directional. I'm not sure how much this has affected the actual result.

After this the car was aligned with a Hunter 511 machine. It seemed to be a pretty old design machine. did not have any 3d sensors but rather clamp ons with wires and a liquid based measuring device on top. Actually i was quite amused and surprised to see the best Balancing machine the Road Force GSP9700 partnered with a Hunter 511.

I told the owner to get a Hunter Elite Hawk Eye to complement the GSP9700 but he said he can get the same results with the 511 as the readings will be the same. Nevermind i told him i'd be happy if he can make my polo go straight.

After this we went on a test drive.... and my car went straight on level roads and on most roads. It drifts left as soon as there is left banking and camber on road. he told me this was normal and that my car is absolutely perfect. He told me to go home and drive my car over a variety of roads and come back in 2 weeks if i felt anything was wrong.

My Observations and Doubts....

1. While driving back over a distance of 20 kms i felt the car going Straight on most roads and for the first time in 4 months of owing the polo i really enjoyed driving it. It felt perfect. this is how my car should have been from day 1.

2. So in course of testing further yesterday i drove around with a friend on board. This time i felt the car tracks straight on most roads but is a bit more camber sensitive. i.e when i'm alone then on left cambered/banked roads the car goes straight but with a pax on board it drifts left in same conditions. What could be the reason for this ?

3. Overall I'm satisfied and at peace but a lingering query in my mind is that....

here in India most roads have in the range of a bit to excessive camber/banking on the left. Absolutely flat roads are rare. So if i'm driving on left camber roads 80 % of the time then should i not ask the alignment guy to direct the toe a bit to the right so that the car tracks straight on such roads ? But then i guess it will track right on perfect level roads.... right ? i'm a but confused.

cheers.

[brad]

Hey brad,

what does the above statement in bold mean ? The tyres are Hankook Ventus V8 RS 205 55 15.

OEM size were 185 65 15 Apollo Acellere. I went with Broader Hankooks for a more grippy ride with a more planted feel with the broader tyres and added weight to the steering.

Some tyres drift sideways due to manufacturing imperfections. It's not dangerous - just how it is. Some are better than others - that's why I stick with Michelin & Bridgestone (usually).

I'm not concerened about you going to bigger tyres but you set the car up for the bigger tyres, not set car then add tyres (although it's good to see the old tyres & what the wear patterns are like.

i researched further on the internet about left pulling and came upon the term "radial pull". further research led me to read about the Hunter Road Force GSP9700. I found about a tyre shop in my city which has this equipment and made an appointment with him.

Over there the owner explained and showed me how the machine works and post all tyres psi to 32 psi took road force and lateral measurements of all the 4 tyres. and then he then stuck weights on the red line showed by laser.

Wow! Never seem or heard of that but I've been out of the industry for years so there's plenty I'm behind on.

I'm not sure if this affects the overall result as the 4 tag position chart was decided with the tyres being balanced in the other direction. so effectively 2 tyres were rebalanced after the deciding the 4 position chart because my tyres are directional. I'm not sure how much this has affected the actual result.

I'm sure if it's smart enough to work out the run-out it cab work out the direction too

After this the car was aligned with a Hunter 511 machine. It seemed to be a pretty old design machine. did not have any 3d sensors but rather clamp ons with wires and a liquid based measuring device on top. Actually i was quite amused and surprised to see the best Balancing machine the Road Force GSP9700 partnered with a Hunter 511.

I told the owner to get a Hunter Elite Hawk Eye to complement the GSP9700 but he said he can get the same results with the 511 as the readings will be the same. Nevermind i told him i'd be happy if he can make my polo go straight.

The last machine that I used regularly (mid-'80s) was a 1960s era Hunter light aligner that projected a line onto a screen that had degree marks painted on it. It was far better & more accurate than the 1970's/80s era computerised machines that I learnt on. I was considered to be the 3rd best aligner in the district. The 2nd best guy worked with me and taught me about working outside the specifications - he runs a tyre place in New Zealand now.
The best guy in the district had a mechanical aligner with degree wheels & bubble levels & he was still using that the last time I saw him in 2003 (he retired recently) & they now use a modern Hunter system.

You don't need fancy stuff if you have a knowledge of what the angles are all about.

After this we went on a test drive.... and my car went straight on level roads and on most roads. It drifts left as soon as there is left banking and camber on road. he told me this was normal and that my car is absolutely perfect. He told me to go home and drive my car over a variety of roads and come back in 2 weeks if i felt anything was wrong.

My Observations and Doubts....

1. While driving back over a distance of 20 kms i felt the car going Straight on most roads and for the first time in 4 months of owing the polo i really enjoyed driving it. It felt perfect. this is how my car should have been from day 1.

2. So in course of testing further yesterday i drove around with a friend on board. This time i felt the car tracks straight on most roads but is a bit more camber sensitive. i.e when i'm alone then on left cambered/banked roads the car goes straight but with a pax on board it drifts left in same conditions. What could be the reason for this ?

3. Overall I'm satisfied and at peace but a lingering query in my mind is that....

here in India most roads have in the range of a bit to excessive camber/banking on the left. Absolutely flat roads are rare. So if i'm driving on left camber roads 80 % of the time then should i not ask the alignment guy to direct the toe a bit to the right so that the car tracks straight on such roads ? But then i guess it will track right on perfect level roads.... right ? i'm a but confused.

cheers.

Australian roads are usually quite cambered as well. If it goes straight on a flat road it will drift left on a cambered road. Adjust for the camber & it will drift right on a flat road. There's nothing you can do about it. Possibly the tyres may be accentuating the issue. Next time get assymetrics or non-directional/non-assymetric - maybe a Michelin or a higher spec Goodyear or Bridgestone.

At the moment your problem is that you are hyper-aware of any issues with the steering. Just drive it & ignore what the steering wheel is doing.

Toe adjustment will not counteract drifting or road camber.

Read this
Wheel Alignment

and
Tire and Vehicle Dynamics, Third Edition

I learnt a lot from an 1960s American book on suspension design & theory - can't remember the name but it would still be relevant today

[bluey]

Anyone done a DIY alignment using old-fashioned measuring tools???

eg
DIY: Alignment, thats right align your car at home with simple tools.

The printouts from the German wheel alignment machine at the local stealer do IIRC 1-2 decimals on the measurements. Would be not too hard to get that accuracy with simple tools.

Caster sounds the hardest.

[brad]

Anyone done a DIY alignment using old-fashioned measuring tools???

eg
DIY: Alignment, thats right align your car at home with simple tools.

The printouts from the German wheel alignment machine at the local stealer do IIRC 1-2 decimals on the measurements. Would be not too hard to get that accuracy with simple tools.

Caster sounds the hardest.

I think there's been a few guys on this forum that have done there own alignments using various methods and home made tools.

Caster isn't that important on these vehicles.

I haven't bothered because it's too hard to get underneath to make the adjustments with the car still on the floor.

[rana_kirti]

Update on left pulling & new observation.

Hi,

Thought i'll update about my left pull and subsequent solution post subframe alignment. The car tracks absolutely straight on most roads and feels perfect. I'm very happy and grateful for this thread and everyone's help particularly brad.

However i've been observing a new phenomenon which is bothering me...

The steering when turned to right feels slightly stiffer/harder than when turned to the left. As in if I'm getting 10/10 power assist while turning left I get only about 8/10 power assist while turning right. while turning right I feel more resistance. The steering wheels wants to come back faster/harder to center from right then from the left. The difference is not a lot but it's noticible.

I've tried tyre pressure 30 all around and 32 all around but same. i've also tried on 4 wheels from my friend's polo but same effect.

thanks.

What could be causing this ?

[route]

Hi,

Thought i'll update about my left pull and subsequent solution post subframe alignment. The car tracks absolutely straight on most roads and feels perfect. I'm very happy and grateful for this thread and everyone's help particularly brad.

However i've been observing a new phenomenon which is bothering me...

The steering when turned to right feels slightly stiffer/harder than when turned to the left. As in if I'm getting 10/10 power assist while turning left I get only about 8/10 power assist while turning right. while turning right I feel more resistance. The steering wheels wants to come back faster/harder to center from right then from the left. The difference is not a lot but it's noticible.

I've tried tyre pressure 30 all around and 32 all around but same. i've also tried on 4 wheels from my friend's polo but same effect.

thanks.

What could be causing this ?

that should be due to one side having more caster then the other...

[brad]

that should be due to one side having more caster then the other...

That can cause that feeling but the casters are within 0.25 degrees of each other so I doubt that the issue.

rani-kirti: I recall that one of your aligners pulled the steering wheel off to centre it? (yes/no/maybe??) possibly it's that combined with a variable rack ratio (I don't know what Polos have?

Turn the wheel all the way to the extreme left lock. Then count the number of turns to go to the extreme right lock. Divide by two and turn back that number of turns. This should find the mid-point of the steering rack & the steering wheel should be straight & level. If it isn't then they need to get the steering wheel centred in relation to the steering rack and then adjust the tie rods so that the toe is correct & the steering is straight/level when driving.

Apart from that I can't offer any advice other than to stop driving your friends cars as they will always feel different to yours.

[route]

Hi Brad, any idea if I could run into problems in future as I'm running a toe in of 0.09 on both sides. Reason being that if I run anything lesser, the steering feels "loose" and the car drifts left.
Have tried shifting the subframe, the left now has more caster compared to the right but the camber on the right is more than the left, could that be the reason for my Polo pulling left?

Thanks

[brad]

Hi Brad, any idea if I could run into problems in future as I'm running a toe in of 0.09 on both sides. Reason being that if I run anything lesser, the steering feels "loose" and the car drifts left.
Have tried shifting the subframe, the left now has more caster compared to the right but the camber on the right is more than the left, could that be the reason for my Polo pulling left?

Thanks

Ideally you want equal camber or a fraction more -ve on the left.

Toe of 0.09 what? and is that total or per side?

[route]

Ideally you want equal camber or a fraction more -ve on the left.

Toe of 0.09 what? and is that total or per side?

0.09 degrees toe in per side. the left camber is 1.18, right is 1.48. Apparently the available "free play" in the subframe is not enough to even out the camber.

[brad]

I'm really crap at doing toe in degrees/minutes but I believe on a 15" wheel 1' is 0.1mm so you are running 0.2mm toe-in. (maybe???). That's probably OK if that's how you like it.

If you've run out of subframe play then it is what it is.

[bluey]

I thought standard toe kept right hand wheel straight and left hand one toed in for RWD (front wheels always loaded by some drag esp braking). This to allow for average road camber which would see most cars gently drift left on a cambered road.

I thought generally, FWD were neutral to toed out (mix of pull from drive and drag from braking). The specification on the first page of the thread says toe +10' +/-10' = a range from neutral to 20minutes toe out.

[brad]

I thought standard toe kept right hand wheel straight and left hand one toed in for RWD (front wheels always loaded by some drag esp braking). This to allow for average road camber which would see most cars gently drift left on a cambered road.

I thought generally, FWD were neutral to toed out (mix of pull from drive and drag from braking). The specification on the first page of the thread says toe +10' +/-10' = a range from neutral to 20minutes toe out.

yes, but if the customer doesn't like the steering feel & the tyres are wearing OK then you do what you have to.