Engines are made up of a lot of compromises.
One example is the choke size of the carb(s). You want to keep the airflow as high as possible as this gives better atomisation of the fuel which = more power.
But there is a problem. If we select a choke size which maximises low and mid range power then as the revs ris there will be a point where you can't get any more air through the orifice. You will limit power at higher revs.
So lets put larger carbs on! Good idea but....the aiflow will be slower at low to mid revs therefore poorer atomisation and less power. You don't get 'owt for nowt.
This is well demonstrated by the dyno charts wich shows a reduction in low to mid range power if V Boost is opened earlier.
As we know those clever Yameringha folk sidestepped this conundrum with V Boost which maximises the power (or more correctly, torque) throughout the rev range.
