The HS40 is a Flat slide Mikuni Carb.
The stamping on mouth of this one reads “T40 6W” . The jets included in it are in the pic to the right. 1) 2)
Trace: • IH: Oiling & Lubrication - Sub-03F • IH: Body Parts - Sub-01E • IH: Wheels, Brakes & Tires - Sub-02K • REF: Engine Mechanicals - Sub-09N • REF: Body Parts • REF: General-MSR 50 • REF: Body Parts - Sub-30L • IH: Oiling & Lubrication - Sub-03H • IH: Wheels, Brakes & Tires - Sub-02Q • REF: Carburetor, Intake Manifold & Exhaust - Sub-01N