Originally Posted by Viich

Not quite - 20x 1 3/8 is expert size. Uses the same size wheels as mini BMX racing. I know it's should be the same, but the manufacturers claim that it isn't compatible. I haven't tested whether it is or not. They're labeling the tires as 20x2.1" but marking it OS20. This is because if they call it 22" then it can't be used in BMX class racing, only cruiser.