Royal Enfield makes bikes like that, they're around 6k or so. Not bad!
I know you're looking at the side-car, though.
I honestly can't picture myself driving someone in a side car unless we're at war. There's this girl I know in NYC that wants me to get one so she can be a passenger in the sidecar. It just seems like a waste of cash.
Other than taking people with you, I think it is a pretty cool way to bring stuff on a trip without mounting huge cargo boxes. And it would make you more visible to cars.
I've seen a guy around town take his golden retriever on rides in his Ural sidecar.
For using motorcycles in adventure riding, sidecars make the ride more stable on bad terrain. However, the riding dynamics of sidecars are very different from two-wheel machines.
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