Maybe you could put in a thicker base gasket which can help bleed down a little compression . Might make the engine a little smoother , Maybe trhe Power Valves are seized shut .They can get pretty goopey . If they stay shut the bike might detonate or RATTLR CACKLE on top end this is because the COMP is staying high , the powervalve is a compression variable device . Maybe you can retaed the timing a bit ? Sometimes KTMs suck/blow out base gaskets this will lean oput the motorand make it run bad . Check it out . GOOD LUCK