Most of Canada now has a 'One Meter' rule - motorists must give at least one meter of space when passing cyclists. For lack of a meter stick carried on my bike, I estimate that my arm is approximately a meter long, and if a motorist is not within my left arm's reach then they are a meter away.

Where I live (rural Ontario), drivers almost always give me a whole lane if the road is not crowded, and most of a lane if there are other vehicles around. Two years ago I was travelling by bike in Eastern Canada and was shocked at how close cars were passing me, even though they had a one meter rule there, too. I was shocked until I stuck my arm out and realized the cars are more than a meter away, but I am just so used to have cars give me the whole lane.

This is what the OP reminded me of. I would expect a motorcycle and a bicycle can share a lane safely and have, close to if not exactly, one meter of space.