In the bike construction montage, Dan lays down red paint on a tank. There are no red tanks anywhere on either his, or Virgil's bikes, or in the shop that we see. Since the montage was supposed to be about building Dan's bike, this makes no sense.
When Virgil is chasing Dan down the hill in the red Cadillac, in one scene from inside Dan's car looking back, the driver is on the wrong side of the Cadillac.
[1:28:47] you can clearly see that bloods pistol has not ejected the round completely after shooting the convenience store attendant.
During the bike build, a rigid motorcycle frame is dragged in, the bike that Saxon is seen riding later is a Softtail.
At the conference of state and federal agencies, Price is listing the federal agencies, "FBI, DEA, ATF, and Treasury". The ATF is one of the agencies of the Treasury Department.
When they drive away after the incident with the cop, the shotgun is left on the trunk of the car as it drives away.
During the lovemaking sequence, a rather visible hand from off-camera can be seen reaching in and catching the lamp as Linda Fiorentino pulls it to the floor.
When Dan meets Renee at her house just prior to the San Carlos Run, a crewman becomes visible at the right edge of the round mirror behind them on the wall for about a second.