Probably the best sidecar, manufactured in Thailand, I have seen is the reinforced glassfiber sidecar from Tiger Motorcycle. The same sidecar they used, and probably still use, on the Tiger Retro 110, I'm sure that with some serious mechanics you can covert the Tiger sidecar to fit the Honda Forza 300.
Of course getting the Honda Forza 300 registered as a legal sidecar combination is a whole different story. To do this smooth Honda should share some chassis design specifications with the mechanics who attach the sidecar to the frame (something what will probably not happen). Also the mechanic who attach the sidecar to the chassis should write a report on how the stress from the sidecar is spread on the scooters frame... (also something what you probably not get...)
But even without the help from the manufacturer and the mechanic you can get the combination registered, it only cost a bit more (+/- 30,000 THB) and probably one or two months. (Both the amount of money and the time it takes is based on past experiences and not necessarily apply on this situation. The vehicle I refer to was unregistered to start with)
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Covered in Side Car
