Ok well I got a flat yesterday (or at least a slow puncture) so I swapped the the tyre for the spare - once I pulled the tyre off I was shocked by what I found...

The white bit is the metal band.

I've checked my tyres before, but the good bit was on the side I could see and the bad bit wasn't - my other rear is like this as well.

Obviously I need a new set of tyres (and the fronts are low ish so it'll be a complete set), but I wondered if you could think of any reason why it might have done this? I am quite... vigorous with cornering which explains why the fronts are low but i've never so much as even locked up the rears (except once on a wet dual carriageway but thats another story...). I was going to get it serviced soon now i'm racking up 360 miles a week + social but I haven't had a break long enough to actually get it done - although next week I do have some free time where I don't need to use my car.

I fee like a total knob for not checking them properly though

So - any idea what might cause such an... odd wear pattern?

EDIT - Usual bits, standard Proton Wira suspension wise, tyres are 186/60/14 on standard 14" steels, the tyres shown are Debico Furio or something which are a value brand from Goodyear.

Tracking is out, my roadster does it as well, i bet if you put the steering wheel in the dead centre position and look at the front of the car then one wheel will be near enough straight and one will be steered out to the side, quite a way by the look of that tyre mate.

You said that those were on the back though, so i guess that the fronts and rears have been swapped over in the past to make the tyres last a little longer, that or the rear tracking is out if wiras have 4 way adjustable tracking, as i cant remember if they do or not..

Take it to a shop and get a wheel alignment done. Costs about $50-70 where I am.

They are rear wheels so i'm not sure what difference the steering would make?

Possible Causes

Straddling speed bumps/cushions. NEVER EVER EVER EVER EVER EVER try and straddle them, even in a work vehicle. Someone else might suffer the fatal blowout your driving caused.
Improper alignment - get your toe in/out checked regularly, i.e. every time you get new tyres
Understeer plus steering too much - being a "Roundabout Hero" with too little talent.

Plus others, but I'd put money on one or both of the first two in most cases, and all three with you Jack

Edit: Oh rear tyres. That rules out option 3 then

Some cars have 4 way tracking, although weather wiras do or not im not sure, that or a previous owner has swapped the fronts and rears around to get a little more life out of the tyres, i would check the fronts as well and see if they have started to do it.

My roadster was so bad that i had anly had new front tyres for just over a week and you could see where it was feathering the tread on the inside edges already!

I did mine myself by eye so it is better than it was but not perfect by any means, needs doing properly at a garage.

I must confess I dont actually know what "straddling" a speedbump is...

Alignment - Ok. How much and does pretty much every garage do it?

Understeer would not affect the rear wheels, nubbin. Oversteer hero in a FWD car would be impressive :P

EDIT - The fronts are fine, I don't honestly know if the tyres were swapped as although the previous owner was my Mum she doesnt have any recollection of what happened...

Looks like wrong alignment and a pretty agressive camber to me

Bent/loose rear suspension?

Quote from RasmusL :

Looks like wrong alignment and a pretty agressive camber to me

Thats what I was thinking, surely thats the only way you could end up with so much wear on one side of the tyre.

yeah, thats hellish camber that is if it is the cause, jakg's motor looks like

/-----\

Straddling is when you try to drive 'over' the bump, with your wheels on either side of it. As in the verb to straddle. All it does in the majority of cases (except on very large vehicles - Transit size vehicles will still suffer from thos) is wear out the inner edge of the tyre on the chamfered edge of the speedbump.

One day it'll wear down enough, and the tyre will fail. You'll either get lucky and see you have a flat tyre, or it'll fail at the point of highest stress - sadly that coincides with the highest speed, and hence you probably die.

Speed cushions are for slowing you down. I don't approve of them in the slightest (they kill more than they save), but I'd rather go slowly though towns and villages than die on a motorways because I tried to save 11 nanoseconds.

I would say (albeit without evidence other than my own experiences) that younger drivers, who think they are the bees' knees and drive aggressively and quickly as if they need to prove something are more likely to straddle, and then die. This is good for population control and natural selection, but bad for insurance premiums, taxes, and the mental health of your loved ones.

Ok I never realised there was so much finesse to driving over speedbumps, I simply drive over them, slowly, straight on...

The best way is to either drive over them completely, at a safe speed OR to drive one wheel over it, and the other on the road.

Note that the edges (front and back, as well as the sides) of the humps can become worn and sharp, so using them at all is a risky business. Try to look at the hump as you approach, and drive your wheels over the areas of the hump that is least likely to later kill you.
Even better, take a route that avoids them altogether.

Then write to your MP and council every time you see a bump that looks even vaguely knackered. Not email - write. Maybe, if enough people do it, they'll dig the fecking things up and make the roads instantly 50% safer.

You can also damage your springs, dampers, chassis, exhaust, brake lines, wheels, uprights, suspension members and pretty much any part of your car on an innocent speed hump. They kill. They are evil.

I don't think he's talking about traditional road-wide ones, but these:


Which admittedly I straddle, but usually because otherwise I'd need to be in the middle of the road.

Oh we dont have any of those round here - but i'd drive over the humpy bit anyway (if possible).

Those are probably the most idiotic speedbumps ever designed.

I agree. Most cars are wide enough to not even touch them when passing over them. And that sort of defeats the purpose of them being there. Cost saving measures, eh? Genius.

That's the trouble - you THINK you aren't touching them, but in fact the inner edge of your tyre is forced to climb the damaged edges, wearing them out, cutting the tyre and causing all manner of danger for you and other road users.

Drive in the middle of the road to navigate them. Never straddle/drive 'over' them.

Sooooo how much is tracking?

To check/adjust? Anywhere from free with new tyres, to £150+. If your rear suspension isn't adjustable, then any tracking problems will be due to bent/damaged/worn parts, which will need replacing (which costs money).

We have these, will straddling these cause those possible effects? There are also these horrible square rigid ones in some places near me, which feel like you've hit a boulder even at 15mph. Being a learner driver, I'd like to know whether or not straddling these would effect me when I get my first car. Sorry for o/t.

What I meant was I have 2 options.

Option 1 is to get new tryes from BlackCircles - they offer fully fitted which means "This option includes a new valve, fitting, balancing and old casing disposal at a centre near you, nothing extra to pay". 2x Toyo Proxes that fit my car will be around £99, or all 4 about £198. I'd probably go for 2 now and put them at the front and the fronts at the rear, but I still need balancing.

Option 2 is to become Sam93, and get some wheels on eBay with tyres on them - I found a nice, subtle set of 15" with nearly-new tyres that fit my car, which didn't sell for £60 and have been relisted for £70, but again I still need balancing.

Option 3 is to go down the local garage and see what they can do but I imagine it'd be expensive... (but I will call them now actually).

My local garage does tracking for free, as does the tyre/exhaust place up the road. Presumably with the idea that you'll just get them to fix it while they're at it.

Be careful with Black Circles though - my local place undercut what I paid for my Falkens and offer decent Michelins for a better price. Price them all first, I wish I had.

I never knew/thought about straddling speedbumps - won't do it any more though, seeing as I have to go over about 10 every day on my drive

I'm calling up garages now - so far i've been quoted £30 + VAT for tracking from one and the wheels they couldn't compete with (£39 + VAT was the cheapest they did) and told me to get the Toyos from the intarweb.

The other ones are calling me back, then i'll be calling the Black Circles place.