I have a 17.5 inch bike wheel, and I need to figure out the "distance in millimeters per one revolution of the bike wheel" for programming a bike computer, according to the manual. I am not sure how to go about this. I tried figuring out the circumference of the wheel in mm, but the number was too big (the manual includes lengths for 20"-27" wheels, and the number I got was way too big.) Any help?