Thanks for all the discussion and excellent points fellow Toy owners! Totem is correct that my concern is over-stressing the 22R engine/4-speed manual transmission. I have no concern with the frame because my shorty SunRader is beefy back there and the power assisted brakes are more than adequate to stop the rig on a very steep hill we have here in my hometown in the Ozarks. When I return from a short trip to Los Angeles, (in my Toy of course!), I will drive some progressively more challenging routes towing my trailer/motorcycle combo and report back here. Will be watching gas and oil consumption as well as engine temps like a hawk while testing. I figure if I continue to drive my Toy like it was designed (and Totem described), I shouldn't have a problem. Keeping my fingers crossed the engine/trans can "get er done"! Plan #B is to mount my 1972 Honda CT90 (with folding handlebars) using "old school" 1980s style "basket mounts" to the rear bumper. The DR650 is so much more fun to ride though.....
I would not attempt this in my '82 Gran Sport, even though it's lighter, it has the three-speed automatic with over-drive transmission and does not have a true one-ton rear axle and brakes. Frame extension is not even close to being as strong as the SunRader's either.
Thanks again!
Chuck in Are-can-saw