E50. Techno hunter pipe.
Anything from 14mm to 24mm depending on how you ride, where you want most torque.
Any rough calculations that apply?
Cfm, volumetric efficiency, bore/stroke, displacement, etc. There are calculators and spreadsheets for this. Is it reasonable to think that the engineers at, for instance airsal, have done most of the math for me in designing the intake port for (unmodified) use?
Hope my math is sound here. On this airsal the intake port is approx 270mm sq in the cylinder and approx 320mm sq at the manifold port. That puts the 314mm sq of a 20mm carb throat right in the midrange of these areas.
So smaller than 20mm more low end torque, higher than 20mm more potential gain at high rpm? 20mm carb, by these estimates, seems like a fair place to start.
How far off am I? (edited)