swole650

I have a 14 kawasaki ninja 650r that I nstalled a 58 tooth sprocket on. 520 heavy duty o ring chain.(they make a great stunt bike very similar to 636 without the horsepower) I'm getting some shaking at higher speeds? It did not do this before. Maybe mild vibration would be better. Just feel something in the rear a lil unbalanced maybe. I've been doing burnouts and drifting. Could this be due to uneven tire wear? Any advice or help would be appreciated. Thank u