Cycling is seen in Asia and Africa as something done by poor people who can't afford motorised transport. On the other hand, owning a car, especially a premium brand Western car, is seen as a sign of success in life.
Therefore you will not find many people from those continents living in the West, who actively choose to ride a bike once they are able to afford something with an engine in it. The kids will ride bikes, but generally they don't do so as adults.
Go to any area with a wealthy ethnic population, and the roads outside their houses are bumper to bumper with Mercedes, BMW, Audi etc. You will still see some ethnic cyclists going to work, usually those who do low-status, relatively low-paid type work. You won't find many ethnic business owners or doctors etc, riding bikes by choice. If they can afford a nice car, they buy one. When was the last time you saw someone of Chinese origin riding a bike in London? They are very few and far between, even by general ethnic standards. You can't force people to like cycling if culturally they associate it with poverty!