I bought a Pulsar 150 CC on 2-Feb-2011. A click sound comes when i use the back brake. I immediately took the bike to the service center, the mechanic told that some soil particle goes into the braking area which causes the sound and he opened and cleaned the brake shoe and drum and fixed. But still i get the sound and now i get the sound even when i am not braking. A very low click sound comes from the back wheel while driving, which can be heard when driving in silent areas. Is this normal? Should i check again? Is there any other problem?