pedaller vs rider

pedaller and rider both are nouns.

Word	Noun	Adjective	Verb	Adverb
pedaller	Yes	No	No	No
rider	Yes	No	No	No

As nouns, rider is a hypernym of pedaller; that is, rider is a word with a broader meaning than pedaller:

pedaller (noun)	rider (noun)
a person who rides a pedal-driven vehicle (as a bicycle)	a clause that is appended to a legislative bill
	a traveler who actively rides an animal (as a horse or camel)
	a traveler riding in a vehicle (a boat or bus or car or plane or train etc) who is not operating it
	a traveler who actively rides a vehicle (as a bicycle or motorcycle)