Be it Bikes or Bicycles, chain and cranks are commonto both.
Chain and the crank get dirty as you use your cycle. The dirt which is basically sand / fine mud needs to cleaned off , else it eats away the crank and the chain. Clean it regularly to extend the life of your bicycle/ bike.
KKE Zap Grease is a very powerful degreaser and can be used for variety of applications apart for chain cleaning. It can be used for engine cleaning, tyre cleaning, industrial cleaning etc. The fact that it is Biodegradable and eco friendly makes it even more wonderful.