Moto Guzzi V700, V7 Special, Ambassador, 850 GT, 850 GT California, Eldorado, and 850 California Police models
Dellorto VHB carburetors use a flat or square throttle slide. These slides were available in various sizes: 7454-60, 7454-50, and 7454-40, to name three. The difference between the slides was in the amount of cut-away on the side that faced away from the intake manifold (the back face).
A 7454-60 was cut back 6 mm.
A 7454-50 was cut back 5 mm.
A 7454-40 was cut back 4 mm.
The photos below demonstrate the differences between Dellorto 7454-60 and 7454-40 throttle slides.