Amazon.com: LEGO Parts and Pieces: Large Black Tire and Black Wheel Pack - 8 Pieces : Toys & Games
Lego - Dimensions
Wheels chart - Swooshable
LEGO wheels | 3D CAD Model Library | GrabCAD
bricks'n'gears: Lego wheel and tire chart
EV3 Lessons on X: "In honor of π day.... Did you know that we have a Wheel Converter: Automatic Distance to Degrees Calculator that uses π? You can measure in centimeters/inches and