diesel4life refer to the specs below. With my racks front and rear, extra fuel can and saddle bags it's getting close to 675 lbs and maybe 700 lbs.
HONDA FOREMAN 4X4 ES ESP
Engine type ... liquid-cooled, OHV, single-cylinder, 4-stroke
Displacement ... 475cc
Bore & stroke ... 92. 0mm x 71. 5mm
Fuel system ... 36mm Keihin EFI
Starting ... Electric (Optional recoil back up)
Transmission ... 5-speed push-button with automatic clutch & reverse
Final drive … Shafts
Suspension/Wheel travel
Front: Dual A-arms w/ 6. 7"
Rear: Swingarm w/6. 9"
Brakes
Front... Dual hydraulic discs
Rear... Sealed drum
Tires
Front... 25 x 8-12
Rear... 25 x 10-12
Length/Width/Height... 83. 7"/47. 4"/47. 4"
Seat height... 34. 7"
Ground clearance... 7. 6"
Wheelbase... 50. 4"
Fuel capacity... 4. 0 gal
Curb weight... 626 lb. (wet)
Colors... Red, Olive, Camo
Price... $7699
Yesterday I did exactly what you mentioned and pulled out 2 smaller sheets of 3/4 inch plywood that I will lay down on the tailgate. That way when I park the quad on it for the trip it'll distribute the load more evenly and some of it to the bed of the truck.
FYI - Yesterday I noticed that from the past trip I did with the quad there are two slight low spots on the tailgate where the tires road for 22+ hours. Glad I caught it before they became too big.