While not legal, as with a lot of things in Thailand there is zero enforcement, and sidecars are very common. Almost without exception, they are locally made contraptions mounted on Honda Waves, and used to haul about noodle vendors and the like. There is one local manufacturer of canoe style fiberglass hacks in Bangkok, but not that well engineered nor proportioned. I was lucky enough to find a used Cozy for my 650.
I had to fix it first including:
Custom brake
Interceptor 18" alloy rim, on a Honda hub, with stainless spokes and tubeless tire conversion
Replaced all the bolts with stainless
LED head and spot light - LED to match on the bike since the pic
Proper bare metal re-paint that does not fall off and uses primer
Raptor liner inside and on the belly pan
Brooklands screen on a bespoke mount
Tenax fasteners on a Sunbrella tonneau
Seat with gel pad insert to match the custom bike saddle since the pic
TIG over the bird shit stick welds
YSS steering damper
Fork brace
and a few other small mods......
Pipe on one side, and centre stand removal simplified the mount, but still not happy with the 2 sliding joints and am going to change that next.
This weeks job is a larger front brake
A LOT different than riding a bike!