I can't complete the easy track, because the bus keeps getting stuck underneath the track during the bumpy part, which causes the time extension to not trigger.
Also, please don't bunch all the controls together on letters when implementing keyboard controls. It's really awkward to have both hands pressing buttons in the area, and depending on the playing to be separately able to move all their fingers on their left hand (which is statistically likely to be their off-hand) is not a good idea. Especially, please don't put buttons that end the race embedded between steering controls. That maximizes the chance that the player will accidentally quit out while doing well.