Bangkok Motorcycle Taxis offer commuters a cheap alternative to the regular taxis and tuk tuks. They are not metered, so you need to negotiate the fare before hopping on. These motorcycles can take one and some times (on short distances) two passengers. They are called win motoesai, and are used by the locals to get in and out of the narrow sois (alleys).
Motorcycle taxis waiting for customers along a Bangkok street https://commons.wikimedia.org/wiki/File:Motorcycle_taxi_guys_at_Bangkok.jpg jeff_leigh