Bought an 07 cbr1000rr with 3000 miles!! However, the dude that I bought it from knew nothing about the bike, there are a few mods that he did not do... So wtf is this thing? On the left side of the bike just chillin...

 

That is your idle adjustment screw. As the name implies, it's used to increase /decrease the rpm of the engine while at idle.
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