The Impulse is built for the dirt, and the manual gives specific guidance for rough riding:
Critical for balancing grip and fuel economy. Oil Grade: Hero 4T Plus or equivalent SAE 10W-30 SJ grade. Hero Impulse Owners Manual
The manual has a symptom-and-cause checklist. Before rushing to a mechanic for a bike that won't start, check this list first. The Impulse is built for the dirt, and