How to reproduce:

1. Open attached project
2. Open scene BikeCOMass.unity
- Scene contains a few bike shapes made out of colliders, all of which have different settings for their centres of mass
3. Play the scene
- Notice how many of the colliders intersect and misbehave in weird ways

Temporary workaround:

float defaultInertia = body.inertia; //save the original inertia
body.centerOfMass = transform.localPosition; //modify the centre of mass
body.inertia = defaultInertia; //reset the inertia to the original value