Whats the stock gearing the 200? Up 2 teeth on the rear is a pretty easy fix.
II will also order the powervalve cover to start with.
I know when Billy Burns was riding for GG and on the 200 he was using the 12T countershaft sprocket. He also used a Rekluse FWIW.
i have billys old 200 with the rekluse,he was running 12/52 combo,the bike hit and pulled like a 250 with some quick shifting,it was a bit much for me though,all it did was pick the front up every where in five gears!! i ended up going to a 13t front and it made a better combo and allows each gear to pull a little longer,i may drop to a 50T rear and try that out