In Sheffield, motorcycles are allowed in all the bus lanes, apart from 3 specific stretches where it's busses only at certain times of the day and open to all vehicles the rest of the time. Sheffield calls these bus's gates which aren't in the highway code and doesn't sign these differently, and doesn't sign motorcycles allowed explicitly in enough of their bus lanes for the lack of a list of allowed vehicles to be permitted. You just have to know, presumably from getting a fine.

Obviously these things make the councils too much money.