Also ive found Oil to make quite a big difference in noise, In the past (4 years of owning my Pulsar) ive used Motul 10w 40 which was always ok really when running standard boost, Then I tried the expensive Motul 15w50 which was horrible, engine sounded too tapety and I had rattle on startup, that came out pretty quick. Now i only use 10w50 Sikolene which I find perfect for the engine, sounds sweet as a nut.