When Mike and Scott are biking it to Idaho, and Scott is having trouble starting the bike, the bike is steady on its stand in the front shot, when Scott is still astride it. When Scott hands the bike over to Mike, and the shot is from behind, Scott's hands are back on the handlebars, they were on the tank, and the bike is not on the stand.
When Mike is in Idaho he has a clear view of Mt. Hood. Not only is the mountain too far away to see (over 200 miles), there is another mountain range lying between Idaho and Mt. Hood, blocking the view.
The goof item below may give away important plot points.
When Scott is spotted exiting his limo, Bob says, "If it isn't Scottie Favor... dressed in a three-piece suit..." In the next frame Scott walks towards the camera with his Italian wife wearing a double-breasted two-piece suit.