(at around 58 mins) When Wilee and Manny are racing in the park and Wilee has to jump the stairs the shot where he makes the jump his handlebars turn into "riser" style, while in the rest of the movie they are "bullhorns"
When Wilee goes to pick up the courier from Columbia University, the map shows he goes from downtown to 116th street. However, when he reaches Columbia University, he is shown to cycling in from uptown.
When the bicycle cop gets doored by the taxi, the door has been visibly modified for the stunt. The window frame has been removed to allow the stuntman to pass over it. In a later shot, the door is back to normal, with the bicycle stuck through the window frame.