DAR ES SALAAM, Sept. 5 -- BEFORE most people step out of their homes, Tanzanias streets are already beginning to come alive. In the early hours of the morning, when the air is still cool and the roads are relatively quiet, boda boda riders begin preparing for another day.

At a small parking area on the edge of a busy neighbourhood, a rider wipes dust from his motorcycle, checks the tyres, tests the brakes and makes sure there is enough fuel in the tank. His helmet hangs from the handlebar as he waits for the first passenger of the day.

For many Tanzanians, a motorcycle taxi is simply a quick and affordable way to get from one place to another. It is the transport people choose when they are late for work, trying to catch a bus, taking a...