using a bus bike rack which slot do you place the bike into?

The one closest to the bus.

That way, if someone else has to load a bike, it won't be hard to get around yours.

Not necessary, just common courtesy.

Being in the rack closet to the bus has 3 distinct advantages: If the bus rear-ends some other vehicle while your bike is on the rack, your bike is a little less involved in the action, It is polite to take the closet rack if you are first to load a bike and lastly, should someone want to steal one of the two bikes on the rack, they will most likely give in to convenience and take the outer-most bike.

Loading your bike on the outer rack has it's advantage too. It is easier to load and unload. Outside of that one simple advantage, I feel it's is best to load your bike onto the inner-most rack when putting a bike on an empty bus rack. At the end of the day it doesn't really matter, as most bike-bus commuters will take the "any port in a storm" mentality and simply be happy that on a 46 passenger bus, only one other person decided to take a bike with them and they still have a slot to put their bike in.

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