Like nobody has ever done it before. D'OH!
These carbs should be using a progressive linkage; one opens first, and the second comes in later. The engine should run well on the first carb alone if you disconnect the progressive link to the second carb.
Start with the operation of the main carb, then visually check your linkage set-up and its effect on the throttle plates, then move on to both carbs. The second carb should maybe start to open at 1/2 throttle on the first carb, and both should be fully open at the same time....you should have some instructions on the set-up.
The linkage set from tom hooks both carbs together in unison. The point is to more evenly distribute the fuel between all the cylinders. Within each carb the secondaries are hook to an progressive linkage that will start to open when the primary is about 75% open.
I can try to hook the actual main linkage as being somewhat progressive by changing the mounting hole locations on one of the carbs arms. However it will not be true progressive but rather just opening at a different rate.
