These bicycles generally have some sort of suspension system to reduce unsprung mass.

For longer bumps that the wheels follow, greater unsprung mass causes more energy to be absorbed by the wheels and makes the ride worse.

As mentioned above, there is a positive effect of unsprung mass.

The 18in alloys are standard, and 2kg lighter, reducing unsprung mass.

This reduces the unsprung mass and hence track wear at high speeds.

Light aluminum wheels may be used reducing the unsprung mass of the wheel assembly.

This reduces the unsprung mass and changes the kinematics slightly.

The ceramic brakes also reduce unsprung mass by around 50% and thereby improve steering response and overall handling.

The locomotives had a large unsprung mass, which caused vibrations that could be felt in the buildings above the route.

This additional unsprung mass was causing damage at high speeds.