Installing VM carbs on the virago - docschops
xv920 jetting, 22.5 pilot 195 main P-6 needle jet, 6DH3 needle  add light pull springs 
xv750 jetting 20 pilot  145 main P-6 needle jet 6DH3 needle, light pull springs. 
These will hook right up to the intake snorkels, this jetting works great for me, may vary on your bike, I'm also at sea level, so that makes a difference as well,

xv920 jetting, 22.5 pilot 195 main P-6 needle jet, 6DH3 needle add light pull springs
xv750 jetting 20 pilot 145 main P-6 needle jet 6DH3 needle, light pull springs.
These will hook right up to the intake snorkels, this jetting works great for me, may vary on your bike, I'm also at sea level, so that makes a difference as well,