27 replies to this topic

[The Matt]

Yeah, it sounds correct/feasible that it's either a bent radius arm or the subframe is out of alignment.  Are both tyres wearing the same?

 

When they said way out, was it toeing out a long way?

[Cooperman]

Which way is it toeing, In or out?

What is the actual measurement?

[The Matt]

One bent radius arm will cause the rear to toe out as an assembly, though.

[Cooperman]

One bent radius arm will cause the rear to toe out as an assembly, though.

Quite right, the rear will self-align to even out the incorrect geometry and thus wear both tyres equally.

[The Matt]

What you need to do, is check EACH rear wheel's tracking in relation to the centreline of the vehicle, rather than just as opposed to each other.

On front tracking, you check wheel-wheel alignment (obviously the front wheels are free to rotate with the steering).  On the rear, you need to align them to the centreline of the vehicle.  I suspect one of your arms is bent slightly.  I also suspect it'll be the N/S as that's more prone to collecting kerbs/potholes/stuff.

[Cooperman]

What you need to do, is check EACH rear wheel's tracking in relation to the centreline of the vehicle, rather than just as opposed to each other.

On front tracking, you check wheel-wheel alignment (obviously the front wheels are free to rotate with the steering).  On the rear, you need to align them to the centreline of the vehicle.  I suspect one of your arms is bent slightly.  I also suspect it'll be the N/S as that's more prone to collecting kerbs/potholes/stuff.

A firm clout against a kerb can bend the arm, the stub axle and the attachment bracket plus, in the worst case, the sub-frame as well.

For the rear tyres to be worn that much so quickly the car must handle badly and have poor road-holding as well.

[The Matt]

Yep. I've bent a radius arm on one of mine in the past. Stub axles are probably more common to bend.

[shaneedwards]

Yes it's both back tyres, although the back drivers side seems to be worse but not by much.

[shaneedwards]

They couldn't give me a reading because it was toeing in off the scale

[Midas Mk1]

Any pics of the rear wheels on the car, in relation to the body?

[Cooperman]

A hard knock on the side of the wheel would cause a lot of toe-out, not toe-in

There is clearly something seriously wrong and the car should not really be driven until it is properly diagnosed and corrected. It should be easy to find if it is that far out and it is surprising that the owner didn't realise something was seriously wrong as the car must have been driving very badly. One of the key things to Mini road-holding and good handling is the rear wheel settings and with excess toe-in on the back it will under-steer badly

[The Matt]

A hard knock on the side of the wheel would cause a lot of toe-out, not toe-in

Yep, would definitely cause toe-out I'd think. Unless the guy with the tracking gauges had them pointing out of the back of the car to get the clearance to use the gauges/see the mirror and read it as toe-in

But, I do suspect a bent component somewhere and from the tyre wear you're showing I expect it to be a good couple of degrees out!

I wonder if you could take some pictures from above the wheel on both sides, from the rear, camera level with the rear edge of the tyre, pointing straight forward along the car and upload them. I wouldn't be surprised if it's visible.

[Cooperman]

Two things to do to get a rough idea:

 

1.  Get a truly rectangular piece of plywood, maybe 1/4" thick and about 24" x 20". Put the car on a smooth level surface and put the plywood vertically against the tyre at the wheel centre each side and see what the camber looks like. Photos would help us on here. You can actually measure the camber using this method and many use it to set the suspension after fitting a new sub-frame (you have to know what you are doing to get it right).

 

2.  Get a long straight piece of wood, ideally about 6 ft long and 3" wide x 1/2" thick. Set this horizontally against each wheel as near in height to the wheel centre as possible.in turn with the length towards the front of the car. This will show you which wheel is toeing-in most. Again, photos if possible.