Winter/Summer tyre temperature

[Somewhatfoolish]

One of the major differences between winter/summer tyres is that the rubber compounds in a summer tyre ain't good below five degrees (say).

But what I am not sure of is if that "five degrees" means the temperature of the rubber, or the temperature of the climate that makes the temperature of the rubber what it is, if you see what I mean?

I basically mostly inspired to ask this question after checking my tyres today when I was on the super dooper fasterest run I've done in ages, I literally had 60 miles without dipping below 100mph, for example, and the whole journey was good, so I have to ask. Also I am drunk for the first time in ages which is nice.

[lppfs997]

The rubber compound of a summer max performance tire starts to harden around 40deg f. Below freezing the summer compound can be nearly as hard as ice. Each manuf. will vary but winter tires stay 'soft' well below 0 deg. f therefore the rubber tread gets worn quickly when driven above 40deg f. These temperatures are the road surface, the air can be colder or warmer, dependent upon local conditions. Note that the amount of moisture on the tarmac can decrease the grip at a higher temp.

[RobM77]

With respect to your high speed run - you didn't say if it was on summer or winter tyres, but if the latter then don't forget the lower speed rating of most winter tyres compared with summer ones.

[MC Bodge]

As I've said on the various winter tyre threads, I suspect that not at all "summer" tyres have exactly the same properties.

I'm an evangelist for Uniroyal rain tyres, which may or may not be the ideal UK year-round tyre.

[nickfrog]

I have been asking myself the same question. I assume it referred to air temperature.

Where I don't follow is that while a summer tyre will have very little grip when first driven in cold temperature, it will take only a few miles for the tyre temperature to go up, after which the air temperature is of very little relevance. Or do the tyre manufacturers always come up with 7 degrees because of the inherent danger of those first minutes ? Which would be fair game to maximise sales.

Also, different summer compounds will generate varying amount of heat and will take varying amounts of time to do that.

Plus, suspension set ups will have an influence on temperature, I assume aggressive camber will generate higher temperatures more quickly.

I have found that Conti SC3 give me amazing grip / traction even at 1 or 2 degrees (except in the snow lol). The loss of grip is far far smaller than the added care that I would use at lower temperatures.

[BusaMK]

My R888s have hugely better grip in air temperatures over ten degrees, irrespective of how much the tyres are worked. I would think road temperature itself is the culprit.