Tyres and speed ratings

[davek_964]

I'm confused.

Highest speed rating seems to be Y - which is up to 186mph. But these days, there are plenty of supercars which are faster than that.

I currently have Pirelli - and I want to replace them with Michelin. The Pirelli are the OEM ones that were fitted when the car was new. They are also Y rated, despite the top speed of the car being over 200mph.
They do have the MC stamp though - which I guess is the equivalent of Porsche N rating. But whether this means they are rated higher than the Y speed rating or not, I don't know.

So what do people with cars capable of > 186mph do? Just ignore the fact that the speed rating isn't really sufficient? (There doesn't seem to be an alternative after all!).

(And before anybody comments, of course I'm not going to be doing over 186mph on the road - but that's not really the point. Legally, I'm not allowed to do over 70mph on the road, but I'd be pretty dumb to fit tyres with a max speed rating of 70mph).

[isaldiri]

it's Y with a bracket that means you are good for higher speeds.

Say on the cup2 on one of my cars.

345/30 ZR20 (106Y)

Speed (Y) is the bit you need to look for rather than simply Y.

[davek_964]

Ah, thanks. Current Pirelli have it in brackets (91Y) so that makes sense.

[bigmowley]

[quote=davek_964]

(And before anybody comments, of course I'm not going to be doing over 186mph on the road - but that's not really the point.

Why ever not?