[Big Dave]

Wheel/tire/hub/brake/drive elements assemblies are reservoir of rotational kinetic energy. More simply, flywheels.

The measure of this rotational kinetic energy is called moment of inertia.

Moment of inertia goes up in proportion to the assembly weight and the square of the diameter.

High moment of inertia is a killer in city driving where you have a lot of acceleration and deceleration. Being inertia it resists changes in velocity - both ways.

You can use this moment of inertia to your advantage if you learn to coast more. All that coasting allows you to 'harvest" the energy you poured into the rotating assembly upon acceleration.