8407.33.90.40 - Not exceeding 18.65 kW

This HTS classification, 8407.33.90.40, specifically covers spark-ignition internal combustion piston engines designed for the propulsion of vehicles classified under Chapter 87, where the engine's cylinder capacity exceeds 250 cubic centimeters but does not exceed 1,000 cubic centimeters. Crucially, these engines have a power output that **does not exceed 18.65 kilowatts (kW)**. This category encompasses a wide range of engines found in various vehicles, including but not limited to motorcycles, ATVs, and smaller recreational vehicles that meet the defined capacity and power output criteria.

The primary distinction for this classification lies in its power output threshold. It is differentiated from its sibling category, 8407.33.90.80, which covers engines of the same cylinder capacity range but with a power output **exceeding 18.65 kW**. Therefore, the kilowatt rating is a critical determining factor in correctly classifying engines within this specific subheading.

As this is a leaf node within the HTS, there are no further subcategories. The classification is finalized at this level based on the engine type (spark-ignition piston reciprocating), its intended use (propulsion of Chapter 87 vehicles), cylinder capacity (250 cc to 1,000 cc), and its maximum power output (not exceeding 18.65 kW). When classifying, confirming these specific technical specifications is essential for accurate customs declaration.