  The structure of edge modes at the boundary of quantum Hall (QH) phases forms
the basis for understanding low energy transport properties. In particular, the
presence of ``upstream'' modes, moving against the direction of charge current
flow, is critical for the emergence of renormalized modes with exotic quantum
statistics. Detection of excess noise at the edge is a smoking gun for the
presence of upstream modes. Here we report on noise measurements at the edges
of fractional QH (FQH) phases realized in dual graphite-gated bilayer graphene
devices. A noiseless dc current is injected at one of the edge contacts, and
the noise generated at contacts at $L= 4\,\mu$m or $10\,\mu$m away along the
upstream direction is studied. For integer and particle-like FQH states, no
detectable noise is measured. By contrast, for ``hole-conjugate'' FQH states,
we detect a strong noise proportional to the injected current, unambiguously
proving the existence of upstream modes. The noise magnitude remaining
independent of length together with a remarkable agreement with our theoretical
analysis demonstrates the ballistic nature of upstream energy transport, quite
distinct from the diffusive propagation reported earlier in GaAs-based systems.
Our investigation opens the door to the study of upstream transport in more
complex geometries and in edges of non-Abelian phases in graphene.
