bicycle rack vs bike rack

bicycle rack and bike rack both are nouns.

Word	Noun	Adjective	Verb	Adverb
bicycle rack	Yes	No	No	No
bike rack	Yes	No	No	No

As nouns, bicycle rack and bike rack are synonyms defined as:

Other synonyms of bicycle rack include bicycle parking rack, bicycle stand, bike parking rack, bike stand.

bicycle rack (noun)	bike rack (noun)
a rack for parking bicycles	a rack for parking bicycles