Continuity mistake: When the three minis are trying to drive up the ramps onto the coach the shot from outside the cars shows them to be on a two lane road while in the shots from inside the cars they are on a three lane road.
Revealing mistake: When the mafia bulldozer is destroying the three cars on the mountain pass, the red jaguar E type has obviously been replaced with a wreck as it has accident damage on it that wasn't there in previous scenes, and away from where the bulldozer hits it.
Continuity mistake: When the Minis are practicing jumping, one of them goes tumbling onto its roof, but the other crashes into another car, denting its wing. Just before the impact, you can see that there is already a dent there where it has obviously already done the same stunt.
Continuity mistake: When the three Minis are driving through a steep turn you see that the chasing police bike overtakes on the inside lane. In the next view from inside the following police car there is no bike in front of or beside the Minis. In the following shot from in front of the Minis looking back the bike is beside the police car behind the Minis. (01:18:00 - 01:26:00)
Continuity mistake: When one of the Minis tries to mount the ramp into the coach it has a bit of silver trim behind the front wheel hanging loose. A few seconds later when it tries again the trim is back in place.
Continuity mistake: In the film, when Charlie just comes out of prison, his fringe suddenly moves to a different position.
Factual error: The amount of gold shown would weigh upwards of 12 tons. That's 4 tons per mini. No way! The density of gold is 19 times that of water; a cubic metre of gold weighs 19 tons. A whole Morris Mini weighed less than 700kg. If you can pay for it, put a block of 10cmx10cmx10cm of gold on the table and see if anyone can lift it.
Continuity mistake: The pile of gold on the coach at the end is far greater than all three minis could carry.
Continuity mistake: The camera on top of the coach shows clear glass in the roof windows but in the long shots they are covered white.
Continuity mistake: When the white mini goes over the cliff edge the rear window is already missing.
Factual error: At the end on the coach the actual coach is not big enough to accommodate the 3 minis, the mini crews, the coach crew and the mini bus crew and the pile of gold. The first mini is parked right behind the driver and the last is literally touching the back doors also as we've seen not much room either side of the minis there simply isn't enough room.
Plot hole: When the minis drive onto the roof of the leisure centre they are trapped - all the police had to do was block the entry/exit ramp.