Basically sportbikes start at 600cc unless you can find a 400 in the Grey Market, but then you will pay through the nose & have a hard time obtaining parts.
So go to a regular riding position bike around 600 to 750cc & you will find some of those are a bit closer to a naked bike with set of flat bars & a set of rear sets you can include. At least a regular riding position bike will NOT be classed at a sportbike.
Is the Suzuki SV-650 classed by your insurance firm as a sportbike & how about the SV-650S? If clean of the sportbike bit then there is a good buy.
If you want a 600 look into a early 90's model. I'm 22 and have a 95 fzr 600r and pay $400 a year through progressive. Covered for $100,000 person and $300,000 accident. The newer bikes will be extremely expensive on insurance depending on your age, especially early 20's.
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