The Apache's engine is not as highly refined as the Unicorn's engine - I'm not complaining, however. But one thing that helped improve the refinement of my bike quite a bit is, taking it easy for the first few minutes of driving. I idle the engine for about 30 seconds and after I start off, I keep the rpm below 2500 for around 5 minutes. This helps the lube oil to reach all the parts of the engine and attain the operating temperature. It's also important that all the parts of the engine get properly heated up before it gets to work hard. Because, if the different engine parts are at different temperatures, the clearance might not be up to the manufacturer's design expectations and hence maybe more friction, more noise. We avoid this by giving it (the engine) some time to acclimatize to the conditions. The result of all this is that there's a noticeable difference in my engine NVH - for the better.