I picked up a mountain board tyre for a tenner including the innertube. The tyre when cut exactly in 4 seems to fit perfectly over the hoof! Bike tyres are about 2 inches wide, the hoofs are 2.5 inches wide, as are the board tyres. I will play about with different attachment methods, but the rubber is thick and very grippy. The only bugger is cutting them, as they have a steel belt, which required a bit of effort (effort? nooooooo!) to cut with a hacksaw. Some more expensive board tyres come in blue and red for those that like colours i.e. me!