So it's well known that if your rear off-side tyre shows extreme wear a dodgey Portuguese arm can be to blame.

But what about the near-side?

I was looking at a 54 ripple today that has a 'van' type side exit exhaust. Bob was saying that his near-side rear tye wears extremely badly on the outside edge. I had a look at the Mehari which also has a short exhaust and found that on her too, the near side tyre is wearing really badly.

The theory is, that with short side exit exhausts, the heat softens the rubber to the extent that when cornering, the rubber wears off much more quickly due to the heat.

This is new to me, anyone had experience of it?

No but if you're worried about it shove a little halfords or other tailpipe extension piece on to take the exit a little further past the wheel

But won't it then be illegal as it'll extend beyond the body?

Measure the distance between the exhaust tailpipe and the tyre. Then measure the distance between the exhaust tailpipe and the thermoplastic side panel on a Mehari...

Then measure the distance between the front tyre and the swan-neck.

Don't forget to take into account the relative temperatures of the tailpipe and swan-neck, and the direction in which heat travels most freely.

FWIW, the turbo on my Saab is around two inches from the radiator top hose, with nothing but a single skin of steel as a heat shield. There's vac tubing considerably closer, without the heat shield, but they're not vertically above it.

In short, I _really_ wouldn't worry about it...

ditto what Adrian says,

Ive run short tail pipes on most things for years, they have never shown that symptom.

I think this is a case of if you go looking for a reason you will find one (but not always the correct one)

I agree with Matt/Adrian - I've driven many A-series over many thousands of miles with Van tailpipes and never had a melting problem.

Whilst we're on this subject, in my experience it's just as likely that you'll find a nearside rear arm that's out of tolerance, so wonder where the idea that's it's only the offside has come from?
I know that I've corrected the alignment on both sides and if anything, it's the nearside which seems to need work most often.
Easy enough to check anyhow, once you've got the string lines out to set the tracking at the front end.

ken
( Re. exhaust gas having an effect on how a tyre wears: it's a bit too early for April Fool's Day, isn't it? )

Well, I s'pose it's _possible_, if...

....if you get too close to the tyre with the polishing wheel as you clean the stainless exhaust on your Cobra?

Here's an idea, take the car for a thrash a d get it nice and warm, jump out and feel both rear tyres. I doubt you'd be able to distingush which was warmer. Take into account the cooling effect of the air going past it, I doubt it makes any difference atall.

Adrian, either that's a very rare 4pot cobra, or it's got another exhaust the other side which would negate any heat difference between the rear tyres. I reckon you'd go through tyres on that on a weekly basis regardless of where the exhausts were.