Dunlop SP9000 tread 'tears'. - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

AUII XR8 · 10-17-2002, 00:42

I was looking at my SP9000's today and they have tearing through the outer tread pattern. These seem to go quite deep into the tread - its almost as if cut by a knife - but is every 5 to 10 mm (or less) right around the whole tyre. This has only happened in the last month. At 9oookm they were fine, now at 9600km they have these lil 'cuts'. Is this common? Recently had a constant high speed run of 150 - 200kmh over 20 minutes, but these tyres are speed rated much higher than this. Tyre pressures always check and adjusted. Dunlop agent in NZ (Beaurepaires) has looked at them and doesn't know why they are doing it. Suggested a tech rep look at them.
Another tyre shop suggested heat fractures. Any suggestions?

10-17-2002, 01:17

I have noticed this is a common problem with that particular tyre over the past two to three years.

Most of the time we were under the assumption that the tyre would break down from doing a lot of U turns and hard acceleration from standstill.

It appears to be peculiar with that tyre because the FM901 doesn't have the same problem. Personally not a fan of the SP 9000 as it has a shocking tramline tendency, particularly after 10k's.

Tyre pressures on the XR's we run are 37 front 36 rear.

T3man · 10-17-2002, 03:25

AUII XR8> What pressures are you running?

Mine are doing it too - a tyre place recommended I increase pressure to a min of 42 psi all round - the Ford figures are 30psi all round which is ridiculously low. I was running mine at 40 fr and 36 rr - still am, as 42 all round was just too harsh.

I put it down to my demanding cornering style which was causing the cuts. It is basically a heat problem which is why higher pressures are recommended.

I'll be trying a different tyre next time. Although I must add I have been impressed by their wet grip and also they are wearing quite good for a high performance tyre - I have 18,000km on them and they have about 3mm usable tread left so I'm looking at getting maybe 25,000km from them. Like I said, I do "test" them out so this mileage is OK by me.

squiz · 10-17-2002, 05:56

we're running sp9000's on XR8 utes. originally ran 38psi front & rear but tyres feathered badly so cut them back to 32psi which flattened the tread back. Got 42000k's out of first set on H's ute. I've got 24000k's on mine,I recon about another 5-8000 left. Both utes driven hard,no loads,city & country use.

AUII XR8 · 10-17-2002, 22:30

I run between 34 and 40 psi, depending on what sort of driving is to be done. Have not underinflated at all, so tyre has been run within correct parameters.

As for heat damage, these are supposed to be rated to withstand heat aren't they? Heat = driving heat, not heat from a hot road in the desert (which we don't have here).