Sorry for the delay, I couldn't find my Dennis Kirk I needed for a converson chart.
For the front (MT90B16) MT is equivilent to 130mm or 5" so you should be able to go with a 130mm which wouldn't add anything to the width. The best fit would probably be 130/90H-16. The Avon AM41 comes with Wide White Walls in the MT90 HB-16 WWS.
For the rear (160/80HB-16) 160 is equivilent to 6.25". If you wat to go wider you should be able to go to a 170 which would add another .25" to the width. If you go 10 wider you'll also have to go down 10 on the aspect; 160/80 would change to 170/70. This one is the hard one because I can't find any WW rear tires over 150 wide.
Retired USAF, IYAAYAS!
2008 V-Star 1100 Custom Bobber project
2011 Crimson XR with Forged Highway Bars / Hard Bags / Passenger Backrest, Ness parts including Smooth Layback Plate Frame/Mount / Rad 3 Mirror / deep cut grips / drivers floorboards /shifter peg / brake peg / passenger pegs. Witchdoctor black rack, Lloydz filter / timing wheel / VFC III, 7Jurock windshield, Drag Specialties seat.