Tyre Wear

[osteo66]

Inspecting my tyres earlier today and noticed that the fronts have feathered the inside 10mm (drivers side more than passenger) to the extent that they have lost the majority of the tread, annoying/expensive as the rest of the tyres have 7-8mm. Is this a geometry problem or would a tracking adjustment take care of it? I run 34-35psi normally.

Thanks,

Dave

[Tony-Bones]

Geometry i'm afraid....

Tracking wear is lateral... The more severe the miss-alignment the more tread area is involved. Since you describe 10% of the tyre width then the likely criminal is camber.

Additionally tracking is a reasonably sedate angle offering gentle wear over a long period, whereas camber is an aggressive angle able to take the tyre to the wire in a few 1000 miles.

[osteo66]

Geometry i'm afraid....

Tracking wear is lateral... The more severe the miss-alignment the more tread area is involved. Since you describe 10% of the tyre width then the likely criminal is camber.

Additionally tracking is a reasonably sedate angle offering gentle wear over a long period, whereas camber is an aggressive angle able to take the tyre to the wire in a few 1000 miles.

Hmmm..thought it might be from threads i've read. Just had the rears renewed and the originals had more wear on the inside edges, I'd like to protect the investment by getting it set up properly. How far in advance would I need to book in? Perhaps you could pm me with cost?

Many thanks,

Dave

[Tone the Bone]

Inspecting my tyres earlier today and noticed that the fronts have feathered the inside 10mm (drivers side more than passenger) to the extent that they have lost the majority of the tread, annoying/expensive as the rest of the tyres have 7-8mm. Is this a geometry problem or would a tracking adjustment take care of it? I run 34-35psi normally.

Hi Dave,

I have also had this problem, was told by main dealer it was the tracking, on my April 05 new model GS300. I had done about 25,000 miles, and needed all four tyres replacing. When checked at an independent well rated tyre dealer, they found the tracking to be spot on, with the new tyres fitted. Therefore no adjustment was made.

I have now done a further 5,000 miles and I haven't checked - I have glanced at the tyres, but haven't studied them.

Regards,

Tony

[Tony-Bones]

Inspecting my tyres earlier today and noticed that the fronts have feathered the inside 10mm (drivers side more than passenger) to the extent that they have lost the majority of the tread, annoying/expensive as the rest of the tyres have 7-8mm. Is this a geometry problem or would a tracking adjustment take care of it? I run 34-35psi normally.

Hi Dave,

I have also had this problem, was told by main dealer it was the tracking, on my April 05 new model GS300. I had done about 25,000 miles, and needed all four tyres replacing. When checked at an independent well rated tyre dealer, they found the tracking to be spot on, with the new tyres fitted. Therefore no adjustment was made.

I have now done a further 5,000 miles and I haven't checked - I have glanced at the tyres, but haven't studied them.

Regards,

Tony

Unfortunately the tyre industry has conveniently built a wall of miss-information regarding alignment..... Maybe this will help?

Tracking/Alignment

Is linear, this measurement shows no concern for any other angle. This form of measurement is the most common in the World and the most damaging.

Angles measured 1

Four wheel Alignment

Uses the rear wheels as a scale to centre the steering rack.... then the front toe..... this is better but is assuming the rear is centred.

Angles measured 2

Four wheel Laser Alignment

Same as above.... be wise!

Geometry/Primary

Will image the exact rear centre line to permit a centred steering wheel.. additionally the front and rear camber positions will be measured. This is the most common form of Geometry and i consider this as 'basic'

Angles measured 8

Full Geometry/primary and Secondary

Is absolute but harder to understand. Few places even with the equipment measure the Secondary angles, these include...

Castor

KPI/SJI/SAI

Scrub radius

included angle

TOOT/Ackerman

Delta curve

and so on

Most areas that involve rapid tyre wear or handling issues need to be read from the 'Secondary' data, even more important if the car has been modified or for diagnostics after an accident.

Angles measured 15+

Not easy reading indeed, millions of pounds change hands every day for 'Alignment', a need to be wise could save you £ssss

One more thing to make the 'blood boil'.. The Primary and secondary Geometry has a customer destination?

1: Primary is the 'dumb' customer version

2: Secondary is withheld unless requested and named the 'Technicians version.

[88b]

One more thing to make the 'blood boil'.. The Primary and secondary Geometry has a customer destination?

1: Primary is the 'dumb' customer version

2: Secondary is withheld unless requested and named the 'Technicians version.

very well explained but then you obviously know what your talking about. A lot of tyre shops can't be bothered to do it properly even if they have the right equipment. Or the 17 year old hasn't a clue apart from a rough idea of tracking. I just change all the shocks and lower arm bushes on the Soarer, no way can you get it back to where it was, so it had to have the full geometry set up again. Drives much better now.

[Tony-Bones]

One more thing to make the 'blood boil'.. The Primary and secondary Geometry has a customer destination?

1: Primary is the 'dumb' customer version

2: Secondary is withheld unless requested and named the 'Technicians version.

very well explained but then you obviously know what your talking about. A lot of tyre shops can't be bothered to do it properly even if they have the right equipment. Or the 17 year old hasn't a clue apart from a rough idea of tracking. I just change all the shocks and lower arm bushes on the Soarer, no way can you get it back to where it was, so it had to have the full geometry set up again. Drives much better now.

Thanks..... The wheel alignment con is one of the reasons i built wheels-inmotion in the first place..... The topic is complicated and most tyre centres rest on wheel alignment as the criminal for all wear or handling problems.

Over the years we now have what i call the "Hoover" scenario?.... Most people who want something to clean the carpet say they need to buy a Hoover....They don't

What they need is a vacuum cleaner!..... It's all down to marketing and the fast fit industry have rested in miss-information and ignorance for to long....... What really angers me is the fact that the only one who suffers is

YOU!

[88b]

That is so true, the motor trade in general has a bad name, yet there are many in it who are totally honest and very competent but the bad ones get everyone else a bad name. What always surprises me is they will be happy to pay someone £50 call out to fix their washing machine, then fork out another £150 on parts and only wait a week for him to come. Charge them £150 for repairs to their car, that they need to get to work to earn money and your robbing them blind.

[Keith Bowler]

Geometry i'm afraid....

Tracking wear is lateral... The more severe the miss-alignment the more tread area is involved. Since you describe 10% of the tyre width then the likely criminal is camber.

Additionally tracking is a reasonably sedate angle offering gentle wear over a long period, whereas camber is an aggressive angle able to take the tyre to the wire in a few 1000 miles.

Hmmm..thought it might be from threads i've read. Just had the rears renewed and the originals had more wear on the inside edges, I'd like to protect the investment by getting it set up properly. How far in advance would I need to book in? Perhaps you could pm me with cost?

Many thanks,

Dave

Dave

Take a trip to the 'Doctor's' you won't regret it and you will save money on tyres.

Tony set up my Mk1 GS300 and I have just replaced my front and rear tyres and the ones that came off had no abnormal wear whatsoever!

Keith

[osteo66]

Geometry i'm afraid....

Tracking wear is lateral... The more severe the miss-alignment the more tread area is involved. Since you describe 10% of the tyre width then the likely criminal is camber.

Additionally tracking is a reasonably sedate angle offering gentle wear over a long period, whereas camber is an aggressive angle able to take the tyre to the wire in a few 1000 miles.

Hmmm..thought it might be from threads i've read. Just had the rears renewed and the originals had more wear on the inside edges, I'd like to protect the investment by getting it set up properly. How far in advance would I need to book in? Perhaps you could pm me with cost?

Many thanks,

Dave

Dave

Take a trip to the 'Doctor's' you won't regret it and you will save money on tyres.

Tony set up my Mk1 GS300 and I have just replaced my front and rear tyres and the ones that came off had no abnormal wear whatsoever!

Keith

Hi Keith - just a matter of time now, the Dr's reputation goes before him - I'm looking forward to a more planted car as well as 'normal' tyre wear!

Dave.

[Kelraine]

Yes - definitely go and see Tony.

My GS handled like a barge before he looked at it - since he sorted the geometry it's been a pleasure to drive and even better, it no longer scrubs the edges of the front tyres.

He really knows what he's doing.

[osteo66]

Yes - definitely go and see Tony.

My GS handled like a barge before he looked at it - since he sorted the geometry it's been a pleasure to drive and even better, it no longer scrubs the edges of the front tyres.

He really knows what he's doing.

Well it's been a week since I've had it set up by Tony - what a difference! The car isn't nervous in a straight line any more and takes less steering input, corners much better with no discernable understeer now and (Tony did mention this from others) the brakes felt slightly stronger. We couldn't get as much adjustment from the OSF as we wanted to but I'm very happy with the result.

I took the opportunity to get under his feet and had a good look around, got thoroughly confused by castor angles and boggled at the amount of knowledge and enthusiasm he shows for his work - Tony, you must have forgotten more about geometry than most have learned!

Interesting to see how the next few thousand miles affect tyre wear now,

Dave.