A caveat to start with, I am not an automotive engineer and know very little about US manufacturing /transport codes. But if you read through the transportation codes specifically 49 CFR Ch. V. The Slingshots VIN code position 8 indicates it is a Class "A" vehicle limited to a maximum of Gross Weight Rating of 1360 kg for 4 wheels (Slingshot has 3 wheels and will possibly be limited to 1020 kg). Subtract from that 75 kg per person, 10 kg per person for cargo, and 50 kg (+/-) for fluids you will be limited to approximately 800 kg for the base weight of the Slingshot itself. These weights are either referenced in this code or the SAE codes. Except the fluids, I am just guessing on that part, fuel, antifreeze, oil, grease, etc.
As I stated earlier, I may be totally wrong on this as I am basically just another idiot with a keyboard and an internet connection, but I would assume this would be Polaris's engineers starting place for design weight limits.
Google search for 49 CFR VIN Position 8 will point you in this direction. Please note that there are lots of words and numbers in those codes and they get boring fast.
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