🔍 Key Concepts

• Study how 4-stroke vs 2-stroke engines affect camshaft speed relative to the crankshaft • Look closely at the cylinder block to see if coolant (blue area) is in direct contact with the liner (wet liner) or separated by block material (dry liner) • Examine the top of the cylinder head to see if the intake valves share a single rocker/bridge or each has its own separate rocker arm

💭 Think About

• From the valve arrangement and presence of poppet valves (no scavenge ports in the liner), decide whether this engine is 2-stroke or 4-stroke and what that implies about camshaft speed • Trace the blue (coolant) region around the cylinder to determine whether it directly surrounds the liner or is separated by another wall • At the intake side, count how many rocker arms contact the intake valve stems and decide whether a mechanical valve bridge must be present

✅ Before You Answer

• Confirm whether the camshaft would reasonably turn at half speed or equal speed to the crankshaft for this specific engine cycle • Verify whether coolant passages are in direct contact with the liner wall (wet liner) or not (dry liner) in the illustration • Verify if there is a single actuating mechanism operating two intake valves together (valve bridge) or individual mechanisms for each valve