(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"
Shortly after the first chase begins, Wilee is shown riding past the same Mobil gas station twice without doubling back.
When Detective Monday hits the thug back after his tooth was dislodged, blood on his face disappears and reappears between shots.
During the first riding scene with Manny the film cuts to Manny's rear wheel cassette. The film shows the cassette downshifting, when during the sequence Manny is supposed to be going faster. A downshift indicates Manny is shifting to a slower gear.
Manny says to Wiley while racing that his Parlee is custom cut carbon fiber. The model Manny rides is the Z5 which is not a custom model. It is a production, stock geometry model.
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.
Outside the flower shop right after bike-riding cop tackles Manny, the practice skid marks from the stunt cyclist can be seen on the ground before Wilee skids to a halt.
When Vanessa is riding, she has a brake on the front of her bike for much of the frame. This is possible due to her having a freewheel on her back wheel. This allows her to coast, as she's shown to do many times. Once she removes the brake after the crash, she would only be able to slow or stop by putting her foot on the tire or dragging her feet. With a freewheel you need a brake.
While Wiley is chasing Manny and being chased by the Bike Cop, when he bunny hops(jumps) down the stairs and over the fence, the handlebar changes on his bike. The style used in most shots is a bullhorn style. During these scenes the bar is a riser bar. This is due to the stunt rider in the scene.
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.
The courier Nima sends is to be picked up from the Law School. However the building shown is not the Law School but Lerner Hall, the auditorium for Columbia University.
When he is chased on Broadway after picking up the package he is crossing southbound by 139th street going to 125th when he is supposed to be biking south of 116th street.