Perhaps I should come at the problem from the other direction. How do I know my tyres are illegal? I have a Bridgestone Gritty ED663 on the front and a Metzeler MC4 on the back. Both manufacturers sites say they're designed for dirt riders, but neither say their not road legal.
There's nothing saying 'not for road use' on the tyre, neither is there an 'E' mark which I'm told thay should have.
Probably the MC4 caused the failure. This site makes a point of saying ED663 "will pass MOT". The description of the MC4 says "special competition" and it's listed in their MotoX section. Basically I think Enduro tyres have to be road legal and MotoX tyres are probably not.
Michelin AC10 road legal motocross tyre. Motocross tread moulded onto the rally tyre carcass.
Not used them myself (yet) but plenty of trail riders round here swear by them in the winter>
I've tryed the gritties and thought they were shite, I now use michi comp3s or AC10s. both road legal enduro rubber as used by Mr Davi Knight and if they are good enough for him at world level there good enough for me
just my thoughts, always found michis good, ride enduros on S12s when a bit muddy and M12s for dry rocky stuff. the comp 3s work very well which when you look at my prilla kicking out 66bhp at the wheel is fair game. had gritties on my 570 katoom and it just wheelspan everywhere and the front felt loose all the time, just wouldn't dig in and grip. i guess its all about how yer ride at the end of the day and what you can afford