A quadricycle includes a four-wheel suspension system that is structured to maintain contact between the ground and the wheels when traversing uneven terrain, as well as to permit a rider to lean into a curve in order to facilitate steering the vehicle. The suspension assemblies are relatively wide to resist rollover accidents. Shock absorbers within the suspension assemblies are angled from vertical to provide both a vertical force component and a horizontal force component in order to permit leaning into a curve while resisting excessive leaning. The quadricycle's drivetrain is structured to increase clearance between the ground and many drivetrain components. Smaller components of the spindle and wheel hub assembly are protected by larger components of the suspension assembly.