Many of Quito’s main thoroughfare have bicycle lanes and on Sunday Av. Amazonas (and perhaps some streets is other neighborhoods) is closed to vehicle traffic so people can ride safely. In the last year they’ve started the program that many large cities throughout the world have adopted, where they have stations of bicycles in various places that can be rented and returned to the same or different station.
Here in Cotacachi where I live it is much more common to see bicycles used for transportation. I also often see bicycle tourist groups here. And on the Panamerican Highway, I’ve often seen more ‘professional’ riders in all the gear. I’m sure there are clubs/competitors in Quito who come this way on the weekends.