They are routed through the head. See the hole between the exhaust valves. The reed valves were absolutely filthy with a sort of asphalt at 62000 km. I don’t have pictures, I dropped them right into carburetor cleaner.
It should. If you find a robust cap. The reed valves have their own gaskets buit in. Couldn’t find the box where I put my valves but found these for Speed Triple on ebay and they look the same. They seem to close when the suction is enough in the exhaust port. They are open at idle .