Despite the presence of many wide roads, Jakarta suffers from congestion due to heavy traffic, especially in the central business district. To reduce traffic jams, some major roads in Jakarta have a 'three in one' rule during rush hours, first introduced in 1992, prohibiting fewer than three passengers per car on certain roads.
Jakarta's roads are notorious for undisciplined driver behavior; transportation laws are broken with impunity and police bribery is commonplace. The painted lines on the road are regarded as mere suggestions as vehicles often travel four or five abreast on a typical two-lane road. It is not uncommon to encounter a vehicle traveling the wrong direction in a given traffic flow. Furthermore, in recent years the number of motorcycles on the streets has been growing almost exponentially. The vast sea of small, 100-200cc motorcycles, many of which have 2-stroke motors, create much of the traffic, noise and air pollution that plague Jakarta.
