At what point do road tyres go "off"?

[tanto]

Recently I've had a couple of unintentional front wheel slides, which aren't good for morale. The bike didn't go down, but even so, I'm no Casey Stoner.



It may be that the front tyre, a Bridgestone BT-090, has "gone off". It's 2-3 years old, and since it's in Thailand it's been subjected to some fairly hot roads. The max air temp when I ride is generally not more than 33C in the shade, although the Tarmac in full view of the sun is likely considerably hotter. The question is, how do I know whether the tyre has had it, or perhaps the fault lies with the road surface (and my riding)?

[CMSMJ1]

That looks old and shit - the cracks inside the tread tell you that it is old.

I'd not trust that for anything other than riding slowly...and then I;d not want to brake in an emergency with it

[Neosophist]

Whats the DOT code on the tyre? It will tell you when it was made.

Honda recommends replacing any tyres not worn out no later than 6 years after they were made due to the rubber aging.

Im not sure if there is a specific day where they go from usable to shit but as they age the rubber does tend to break down so the tyre doesn't offer the same perforamnce.

I took a VFR for MOT that had tyres made in 1986 on it and they were hard as hell and didn't offer any grip but since I wasn't pushing the bike at all they were ok, no doubt they would break traction super easy.

With your tyre, as Mark has said it looks like its had it. I've rode bikes with creep in the tread before but have noticed the same thing as you.

[tigerclaw]

My understanding is that tyres are actually uncured so they continue to harden over time and this would explain why they have an age limit and why they crack over time. Subjecting them to a heat cycle speeds this process. Eg going out on the track warm up, use, cool down. This makes the tyre harden. eventually the tyre has become hard but you still have lots of tread. The whole thing is a process so they don't suddenly go "off" the issue is more that you don't pay attention to it and you push then harder than usual and suddenly notice what had been there all along. I stick my thumb nail into my tyres every now and then to make sure they're still a bit Marshmallowy

[dobbslc]

The 090 is an old tyre superseded by newer versions, check the date stamp on it, it's 4 numbers on the side wall inside an oval shaped marker. Example (1243) means it was made in week 43 in 2012.
I bet yours are much older.....

[tanto]

I'm away at work for another week. When I get home I'll check the tyre for the DOT code and post it here for reference. I'm curious to discover how old the tyre is, to understand whether the "heat cycle" described by Tigerclaw has reduced the life of the tyre. The road surface is pretty hot in Thailand!

[speedy231278]

These days, according to a friend of mine who works for a bike shop, the tyre manufacturers suggest that three years from manufacture is the time at which you should replace the tyres, and that careful storage makes no difference to this. Personally, I think that's sales bluff myself. Of course, it could last less long depending on the use. By the time you have visible signs of perishing or cracking, I would say it's well past the best part of it's life, and time for a new one.

[tanto]

Home five weeks later than planned... For reference, here's the DOT code - VAC3110 - which I assume means the tyre was manufactured in July, 2010.



Four years later, it looks pretty wrecked. In fact, the rubber appears to have cracked and perished some more since the previous photo was taken. As the bike's been sitting in the house during the past two months of "hot season", that's what 39C does for static, old tyres.

As a replacement I've ordered a Dunlop Alpha 13, for about £65.55 at today's rate of exchange (3600THB in Thailand). A bargain.

[Neosophist]

Home five weeks later than planned... For reference, here's the DOT code - VAC3110 - which I assume means the tyre was manufactured in July, 2010.



Four years later, it looks pretty wrecked. In fact, the rubber appears to have cracked and perished some more since the previous photo was taken. As the bike's been sitting in the house during the past two months of "hot season", that's what 39C does for static, old tyres.

As a replacement I've ordered a Dunlop Alpha 13, for about £65.55 at today's rate of exchange (3600THB in Thailand). A bargain.

Yep.

Alpha 13s are amazing tyres btw, they dont last too long though but grip from the off. almost too much hah, makes you want to abuse the bike before theyve properly warmed up :)

[Drunkn Munky]

Id take a wild guess that the heat over there (lucky git BTW) is maybe causing the premature wear, you might be better off with a W rated tyre rather than H rated as lets face it your not going to have any problems getting heat into them.

Send the alpha 13's to me if ya want