My neighbor and I purchased an Activa 3g at the same time. When my bike is in idle (just after immediate start) as well in running condition, it sounds little bigger/ rough noisy like dub dub... Also, the accelerator is not smooth to hand. But I checked very carefully that my neighbour's bike is sounding very smooth and soft (not much noisy) while it in idle/running. I can hear my bike sound from 200 mars away also when it is coming to stop condition. This is not same with neighbor's bike. Even when their bike is close to us it's sound is not very audible. I can say definitely there is some difference in engine sound in my bike.
What could cause this and how can it be fixed? I told the Honda dealer while I went to the scheduled service and he said he did it. But he did not fix it, the noise is the same. What should I do to get soft and smooth sound from the engine?