Tyres (again!); How long does it take to Flat-Spot them?

[ChasR]

Right, its another tyre thread, but a different one?

Let's say an estate car has been sat for 2 years as a non-runners where the tyres went down to 15 PSI in that time. Let's now say it's been pushed into daily use with some minor rectifcation.

In your opinion, would the tyres have flat spotted on a car sat possibly outdoors for that length of time or is it unlikely?

I've had cars sat before for a while, but they didn't weigh 1500kg either and the tyres didn't lose air pressure in that time.

[colnerov]

Hi, I've found that they can but it's not permanent, if you run them for a while and they get some warmth into them they straighten up and run right, if you see what I mean. It might be an idea to check for cracking especially if they have any age to them.

Colin

[Phil H]

I agree with Colin - feasible to get flat spotting within a short amount of time but usually disappears after a good run or two (basically after the tyres have got warm enough again).

[pow]

While I agree it can happen, me and the wife bought an SLK that hadn't been used for 6 months and the fronts were flat spotted and shot, ran them for about 500 miles then had to change them!

[Deleted]

if it were me I'd run them around a few miles at standard infaltion, then over-inflate them as far as is feasible and see if any splits open up. Then run them very carefully at low speeds while overinflated for 20 miles or so, just to make sure they pull back into shape fully and don't decide to give up.

If they are okay then they should be okay back at the correct psi.

But the obvious answer to this is that new tyres would be far safer.


=)

[igor]

When I bought my Wolseley it had been sitting for some time and the tyres were down to around 5 psi but they had plenty of tread left. I drove to the nearest service station, pumped them up to something like 30 psi, and drove 275 miles home with no trouble at all. I didn't drive slow either.

[rwdrules]

our camper often sits for a fair while,as it weighs 3.4 ton it does deform the tyres to a degree, however i actually take it for a short run to a garage,then deflate the tyres to 40 psi(a third less than usuaL) then drive it for around 10 miles to get them very warm, then pump them back up to normal and the slight vibration caused by the deformation has disappeared

[ChasR]

The truth is, I've done around 300 miles (maybe more) and the vibration at 70-80MPH hasn't gone .

That's rolling on stock pressures. I'm tempted to get them balanced to attempt to iron out the issue, just in case the vibration is something else. But the car generally drives well otherwise. It's something my W124 250D didn't have, but that was on new Goodyears all round...

The truth is I'm trying not to spend £150-300 on tyres as in truth, I've woken up a car, albeit low on miles that hasn't run for 2 years due to a relay fault. No car IME likes sitting.

[tommymini]

Tyres will be flat spotted and the carcass compromised letting then get that low on pressure. You are risking a blow out and who knows what damage that could cause.........

Just fit a set of tyres for safety's sake, yours and the general public etc.....

If you can't afford new tyres, stick the car on the drive till you can

[colnerov]

Hi, You could try checking the drive and prop shaft for stiff UJs.

Colin

[igor]

Sept 19, 2018 18:53:19 GMT ChasR said:

The truth is, I've done around 300 miles (maybe more) and the vibration at 70-80MPH hasn't gone .

That's rolling on stock pressures. I'm tempted to get them balanced to attempt to iron out the issue, just in case the vibration is something else. But the car generally drives well otherwise. It's something my W124 250D didn't have, but that was on new Goodyears all round...

The truth is I'm trying not to spend £150-300 on tyres as in truth, I've woken up a car, albeit low on miles that hasn't run for 2 years due to a relay fault.

That may be part of your problem. I always run tyre pressures considerably higher than the manual says. My Falcon runs 40 psi (and up to 46 in the rear when heavily laden). This seems to improve tyre life and definitely improves driveability.