Belt shelf life

Post by **mat_fenwick** » Mon Jan 16, 2012 2:38 pm

Black ones

This has been on a mixture of Firestone, Uniroyal and Vredestein tyres, observed over the last 100k miles or so. Worst was 7k, but I can only put that down to a tyre problem (bad batch?) as my driving style didn't change appreciably.

Interestingly, on some wheels I have here I've checked a few date codes - the oldest is a 1203 (12th week of 2003), used until down to a few mm and then kept as a spare. This is visibly fine, but there are another two with a code of 4607 (stored on a car) which have noticeable cracks in the sidewall. So obviously the younger tyres are the safer ones, right?

Willy · Post by **Willy** » Mon Jan 16, 2012 5:09 pm

mat_fenwick wrote:So obviously the younger tyres are the safer ones, right?

Shurely, this is a conclusion that can be drawn here. Tyres obviously deteriorate in two ways, mechanical wear (usual reason for replacement, when they reach that fabled 1.6), and ageing. As far as I'm aware, ageing simply causes the rubber to become brittle, which can be observed as cracks forming - easily visible around the lettering and distinguishable from kerbing wear. Out of the wheels I bought the other day two look as good as my six month old Michelins, the others are cracked to hell. Not sure if the dates are all the same though, too cold to check now...

Please feel free to correct me!

Post by **mat_fenwick** » Mon Jan 16, 2012 5:26 pm

Willy wrote:
mat_fenwick wrote:So obviously the younger tyres are the safer ones, right?
Shurely, this is a conclusion that can be drawn here.

I was just pointing out that a 9 year old tyre I have looks visually perfect, whilst two tyres just over 4 years old have significant cracks in the sidewall. No hard and fast rule on the basis of that (limited) evidence...

MULLEY · Post by **MULLEY** » Mon Jan 16, 2012 8:23 pm

Everyone's own personal choice to make decisions about safety, i'll be playing it safe rather than trying to save a few quid. Mind you, the spare on my car is the original MXL i believe, so that'll make it 18yrs old

If i ever need to put it on, i hope i'll remember to drive steady & not keep it on for very long.

Post by **Defender110** » Mon Jan 16, 2012 9:26 pm

Old tyres can also have an undesirable effect on the ride quality with their less supple side walls. I scrapped some old tyres that looked perfect but rode terribly.

KevR · Post by **KevR** » Tue Jan 17, 2012 10:18 am

Perversely that's one reason why I'm sticking with the MXLs - they ride so much nicer than any newer tyres I've tried!