Personally I would load the whole outfit bike and trailer and take a trip the the CAT scale or the local scrap yard,gravel pit,concrete or asphalt plant or Grain elevator.All have certified Scales. Weight Steering and Drive and trailer axles and then a total gross for the unit.
"THE TAIL IS IN THE SCALE" my friend .No guessing. If you are getting close to maximum gross U need to know.
Roger & MaryLou
F350 CREWCAB SW LONG BED
7.3 liter Power Stroke Diesel
1977 27ft OVERLANDER
AIR # 22336 TAC- OH-7
May your roads be straight and smooth and may you always have a tailwind!