To objectively assess the real-world operational performance of the Yuchai YCK11 engine, a comprehensive field trial was carried out in strict alignment with the actual operating conditions of intercity passenger transport operators. The trial route spanned from Ho Chi Minh City to Da Lat City, Vietnam (Ho Chi Minh–Da Lat), covering a one-way distance of 325 kilometers entirely on national highways, including highland segments (with average fuel consumption of 24–25L/100km) and plain sections (averaging 21–22L/100km).
This setup fully mirrors the daily operational demands of passenger transport fleets, enabling a holistic evaluation of the engine's overall performance under authentic working conditions.
Two 12-meter highway coaches served as the test platforms: the Xiamen Golden Dragon XML6122K (powered by the YCK11 engine) and the THACO Cruizer120 (equipped with the competing WP12H engine). The entire trial replicated real-world passenger transport operations without any specialized modifications. During the test period, both vehicles operated round trips along the Ho Chi Minh–Da Lat national highway at a consistent cruising speed of 60–100 km/h, ensuring the test data was authentic, valid, and highly representative of real fleet operations. A side-by-side comparison was conducted under identical route, load, and driving parameters to evaluate the core operational performance of both engines.
Following continuous on-road testing, key operational metrics were systematically recorded. A detailed performance comparison is presented in the table below:
|
Engine Model |
yCK11
|
WP12H
|
|
Vehicle Brand |
Xiamen Golden Dragon |
THACO |
|
Vehicle Model |
XML6122K | Cruizer120 |
|
Power (PS) |
410 | 430 |
|
Transmission Brand |
Fast Gear 6DSX200T |
Fast Gear 6DSX200T |
| Main Reduction Ratio | 3.364 | 3.38 |
|
Vehicle Type |
12m Highway Coach |
12m Highway Coach |
|
Test Route |
Vietnam National Highway (Ho Chi Minh-Da Lat), 325km one-way |
Vietnam National Highway (Ho Chi Minh-Da Lat), 325km one-way |
|
Normal Speed (km/h) |
60-100 | 60-100 |
|
Combined Fuel Consumption (L/100km) |
23.4 | 26.2 |
|
Cumulative Operating Mileage (km) |
5354 | 5640 |
- Superior Fuel Economy: Significant Fuel Savings
Field trial data from the Ho Chi Minh–Da Lat national highway clearly underscores the fuel efficiency advantage of the Yuchai YCK11 engine: it delivers a combined fuel consumption of 23.4 liters per 100 kilometers. Relative to the competing WP12H engine (26.2L/100km), the YCK11 achieves fuel savings of approximately 2–3 liters per 100 kilometers at comparable power levels, demonstrating its superior fuel economy.
- Excellent Dynamic Performance: Strong Power, Rapid Acceleration and Low Noise
Beyond its core fuel-saving advantage, the Yuchai YCK11 engine excels in power delivery, acceleration responsiveness, and noise attenuation. Featuring a 2000bar fuel injection pressure, the YCK11 generates robust power and rapid acceleration, maintaining strong performance even on highland gradients to fulfill intercity passenger transport requirements. Advanced structural optimizations effectively reduce operational noise, enhancing driver comfort during long-haul journeys.
- High Reliability and Durability: Low Failure Rate
In terms of overall vehicle reliability, the YCK11-equipped coach exhibits exceptional durability and practicality. Constructed with a 250bar ultra-high burst-pressure cylinder block and high-strength forged steel crankshaft, the YCK11 boasts a lower failure rate and higher fleet availability, ensuring uninterrupted, stable operations for passenger transport providers.
- Stable Quality and Timely After-Sales Service: Enhanced Operational Value
Additionally, Yuchai's consistent product quality and responsive after-sales service network provide reliable long-term support for fleet operators, further elevating the total value of the vehicle.
Based on real-world trial data and operational scenarios, the Yuchai YCK11 engine fully addresses the core needs of passenger transport customers. Deployed on the Ho Chi Minh–Da Lat national highway (325km one-way, all-national-highway route), it achieves a combined fuel consumption of 23.4L/100km, saving 2–3L/100km compared to equivalent-power competing engines. The vehicle is reliable, robust, and practical, while the engine delivers outstanding fuel efficiency, strong power, low noise, and swift acceleration. Backed by Yuchai's stable quality and timely service, the YCK11 is ideally suited for passenger transport operations on the Ho Chi Minh–Da Lat route and similar national highway corridors, offering an efficient, cost-effective, and dependable power solution for intercity passenger fleets.