By belt
By gear
By inlet gas
By exhaust gas
Muffler
Oil filter
Air filter
Fuel filter
Cloth
Paper
Strainer
Wire mesh
To reduce the heat
To reduce the noise
To reduce the vibration
To filter the exhaust gases
Between exhaust pipe and tail pipe
Between tail pipe and exhaust manifold
Between engine head and exhaust manifold
Between exhaust pipe and exhaust manifold