new tread depth??

deep ends on make/model/size of tyre

normal road tyre e.g. toyo for a 13 or 15" tyre

As already stated, it depends entirely on the make/model/size of tyre. I've seen anything from 4 - 8 on normal car tyres.

I'd agree with that, I've never bought new tyres with much less. Mike.

Presumably with a greater tread depth there would be too much flex in the tread blocks and handling and grip would start to be affected.

Thanks - my mate, who said 6mm, owes me a pint then!!

Probably depends on the type of tyre. Those on agricultural type vehicles, like Land Rovers, seem to have a deeper and chunkier tread, but as far as car tyres go, you're right. Anything much deeper than 8mm would have the tread squirming all over the place. Mike.

Mine are about 8/9 in the middle and 4-5 at the sides. Causes the MOT man to give me an advisory every time about the wear rate.

Low tyre pressure?

No i mean from new, right off the shelf.

I always wonder at the advisability of sitting in the waiting room whilst some jerk takes your tyres home for selling on to his mates then charges you top whack for a new pair of shoes and a piece of paper.

What do you mean low tread? Show me!

And tell me where it says vagina on my forehead.

I dont have a photo to hand, but i can assure you i stay with the guy at all times and see the paper labels taken off the tyres - they're brand new, and ive had 3 sets of 2 now, all the same. Ive no problem with it becuase they wear to flat across the lot eventually and all the tread contacts during driving - they use different compounds on the edges I believe. I also know the guy fairly well, he does me free 4 wheel laser alignment because ive recommended a few people because im pleased with his service.

Ive no idea why you have vagina on your forehead :)