I'm writing this hoping that it might help someone else.
I've had my Yamaha FZR600 2003 model for 4 months and it needed a new rear tyre.
I've had one of these fitted as I'm a commuter:
http://www.ityre.com/en/tyres/catalog/avon/model/21381/Avon AV56 Storm
AT 2 Ultra [/color]160/60ZR17 - pumped to 40psi[/font]
I'd heard about new tyres being very slippery and so I was naturally worried. I work with a colleague whose only motorcycle accident was when he'd just put a new rear tyre on and he lost it on the first corner. I heard from the place that fitted my tyre that they see so many people losing it as they leave their place.
So I was worried, especially given I'm still a newbie to bikes: despite having a licence for 2 years I was a Sunday only cruiser (ex Midnight Star owner) and it's only been these last 4 months that I've needed to commute. I've done 2500 miles these last 4 months.
I left the tyre fitter today and went for a ride.
And nothing happened. I've just done 30 miles and absolutely nothing. I ought to mention that I am a bit of a granddad when I drive so perhaps that had something to do with it: I only open it up on straights; but come back down again to take corners probably with less than a 10 degree lean angle - or at least that's how it feels.
25 miles into the ride I stopped and looked at the state of my rear tyre. It looks like I'm just riding on half of the tread - so I'm not leaning over very much. the outer two quarters look untouched.
So there you have it: if my newbie, worrying experience is helpful: it seems that you don't need to ride as if you're on an ice-rink - just ride conservative as I do anyway.
Hope this helps.