Hacks on the wrong side.
I guess you can mount a sidecar to anything...
I'm probably the one guy here that can critique that setup. It's ugly, and, it's mounted on the wrong side. I'm not saying that sidecars coupled to bikes are all ugly, or beautiful for that matter, it's just that some are uglier than others and some, especially mine, are actually aesthetically pleasing (at least I think so)
. That was my goal when I started the T100/Spyder project. The aesthetics were primary and comfort and handling were secondary. After all, I was dealing with a classic bike and I didn't want to destroy the "look" with a hideous sidecar.
Watsonian makes a well built chair (sidecar), but none are pleasing to the eye, especially when coupled to a modern tug (bike). It's quite a challenge to design form and function into an aesthetically pleasing product that not only has storage and protection from the elements but is structurally sound and light weight to boot.
One thing that all modern bikes suffer from and needs to be corrected on a staggered three wheel setup is "trail". Modern telescopic front suspension systems in order to attain the self centering tendency and stable 2 wheel handling that inspires confidence in a rider and his mount equates to lack of trail in the front end geometry. Sidecars need a large amount of induced trail to handle correctly as you "steer" an outfit rather than "lean" it. By steer, I mean like a car. The larger amount of trail allows the dissimilar geometry of the tug and chair to be at harmony with each other. The other problem with telescopic forks is that they aren't rigid enough. The flex as you steer the outfit translates in to wobble and poor handling. Hence, a Earle's leading arm fork is usually fitted as is on the R3 in the picture. The leading arm fork isn't pretty, but allows for the trail to be increased and is light years more rigid than the stock fork. A drawback is that the bike will not handle well as a stand alone unit.
I choose not to refit an Earle's fork on my T100 and keep the standard Showa telescopic unit. The standard fork on my T100 has a custom mounted (fabricated in my shop) fork stiffener under the fender mount, unseen, keeps the front legs from flexing too much. A change in fork oil and internal springing keeps the front end in check 90% of the time.
The R3 would make a good tug. My only qualm would be the lack of a complete under frame that would cause the mount to be difficult. Sidecars need to have a triangulated mount system, like a truss. The need to be 4 point mounted and extremely rigid because the stress of cornering is directly transmitted to the tugs frame, suspension and wheels and that stress can be quite severe especially when "flying the chair"....but that's for another time.