pedaler vs biker

pedaler and biker both are nouns.

Word	Noun	Adjective	Verb	Adverb
pedaler	Yes	No	No	No
biker	Yes	No	No	No

As nouns, biker is a hyponym of pedaler; that is, biker is a word with a more specific, narrower meaning than pedaler:

Other hyponyms of pedaler include bicycler, bicyclist, cyclist, wheeler, unicyclist.

pedaler (noun)	biker (noun)
a person who rides a pedal-driven vehicle (as a bicycle)	a person who rides a bicycle