That is for a car !!
Motorcycles above 50 cc still have the 1mm depth limit, across 3/4 of the width and around the entire circumferance.
Mopeds etc below50cc must have visible tread across and around the tyres.
No Yam, he is wrong .. trying to sell you a tyre methinks.
Bike tyres have wear bars built in anyway, so you should see them.
Although as Geoff says .. bikes dont hadle too well when they get a bit low.
Always change mine well before limit anyhow.
When they changed law from 1mm to 1.6mm they left bikes as was.
Cant remember the year ... .. but sure someone will enlighten us.
Worn tyres is actually a "level 4" offence and as such can result in a fine of up to £2,500, although this is unlikely. Mandatory 3 points though and worse, each faulty tyre is a separate offence!
I do tend to let my tyres get down to the wear markers, but the bike is usually feeling pretty cr*p by then. But I'm doing around 18k a year and so like my tyres to last. If I was doing 5-6k only for example then I'd happily change them early.
Interesting point about the 3/4 width.
There are now road tyres with no tread at all towards the outside edges. Must be at least 1/4 of the total width, but they're sold as road legal.