When evaluating a 125cc Enduro bike, focus on the engine type (typically 4-stroke, air-cooled) for reliability and the frame construction (chromoly steel or reinforced aluminum) for durability. Ensure the suspension system features adjustable inverted front forks and a rear mono-shock with at least 180mm-250mm of travel to handle off-road terrain. Additionally, verify the braking system uses hydraulic discs both front and rear for safety, and check that the tire specifications (usually 17/14 or 19/16 inches) match your target market's height requirements.