.404 on the big saws of over 100 cc because that's the bars I have for the them .084 Stihl, 2 125 Macs ,2100 Homelite ,105 Mac .In addition the older antiquish Mac reed valves all have .404 ,10 or so I suppose .
I once tried a short bar on one of the Mac 125's with 3/8" and it didn't cut as...