I'm not sure if I could work in something as big as the HD Ultra or not. The width of the bike is the main problem, although length becomes an issue from a tie-down standpoint. For a bit more clearance the Spyder rear can be angled, and the bike loaded backwards. Lloaded on the left rear of the Spyder, it is fairly tight for a bike between the wall and the Spyder, but it does fit. Not a problem for getting the my BMW RT in, but no good place to tie it down, so I have not carried that with the Spyder. I could probably move the chocks for the Spyder and the bike farther toward the walls and sneak by, but I haven't tried. I have loaded my BMW R75/5 many times, though, as well as an additional small bike on the right side The best way to see if things fit is by trial and error. When you have an afternoon to spare, load things, and move them around, checking tongue weight and measuring the height at each side near the wheel to see if the load is even side-to-side. Part of the viability of this will be the actual size and shape of the trailer. My trailer is fairly narrow. It may be listed as 7' wide, but it is more like 6'8" inside, and 6'4" at the door cables. The wider the better. My V-nose is a full three feet deep, which allows the Spyder nose to fit very far forward, and leaves more room for bikes. Some v-nose trailers are only two feet deep or less up front.
I know what you're talking about with the trailer measurements too. Our trailer measurements are pretty much the same as your's.....but our nose is smaller, more like maybe 2' if that. I think they round those numbers up to make them sound bigger. LOL And your other bikes are smaller than the Ultra. We've been talking about getting an open flatbed trailer, and have found one we like, but not sure yet if we want to make the switch. We've got a couple months to think about it though.
