Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.
Two strokes. 1-2 Completion of scavenge. Air enters the cylinder, expelling exhaust gas and recharging it for combustion. Scavenge and exhaust ports are open. 2-3 Post-scavenge period. Scavenge ports have closed and some air in the cylinder may leak to exhaust. 3-4 Compression. Exhaust port has now closed and the air trapped in the cylinder is compressed by the upstroke of the piston to raise its temperature sufficiently to ignite the tuel.4-5-6 Fuel injection takes place and combustion occurs causing a rapid rise in the pressure. 6-7 Expansion. Combustion completed, the hot gases expand forcing the piston downwards. 7-8 Exhaust blow down. Exhaust port has opened, allowing gas to pass to exhaust manifold and pressure drops rapidly in the cylinder. 8-1 Scavenge. Scavenge ports have opened and air enters to expel remaining exhaust gas.
Four-stroke. 1-2 Completion of aspiration.2-3 Compression. Air inlet valve has closed, air in the cylinder is now compressed to raise its temperature for combustion of fuel. 3-4-5 Fuel injection. Combustion takes place with the rise in pressure.5-6 Expansion. Combustion completed. Gas pressure forces piston down.6-7-8 Exhaust. Exhaust valve opened, piston expels exhaust gas on upward stroke.8-9-10 Overlap. Air inlet valve opened, while exhaust remains open. 10-1 Aspiration. Exhaust valve closed, piston draws air into the cylinder during down stroke.