cyclist vs bicycler

cyclist and bicycler both are nouns.

Word	Noun	Adjective	Verb	Adverb
cyclist	Yes	No	No	No
bicycler	Yes	No	No	No

As nouns, cyclist and bicycler are synonyms defined as:

Other synonyms of cyclist include bicyclist, biker, wheeler.

cyclist (noun)	bicycler (noun)
a person who rides a bicycle	a person who rides a bicycle