Short video on my HSR42 Mikuni on my bike. Mounted cam on the rear footpeg so the engine could be heard, gas tank mount could barely hear the engine. Not a GoPro, just an old phone I taped on. Still tweaking here and there on the carb and manifold, working on mechanicals and cosmetics. I'm favoring the HSR42 over the HS40, 42 is extremely configurable and easy access to adjustments. 40 not so much, almost seems as if the 40 is made for a left side mounting on a bike. Still testing tho. I'll see. If you're interested...