[Resolved]  Suzuki Gs 150r — Drive Chain Hitting Its box

I have purchased Suzuki GS150R Bike From Margao -Goa. I have driven it for almost 1500 Km. I do not quick accelerate the Bike Nor i carry pillion rider. I have done first servising on 710 Km. where drive chain was adjusted as it was making noise hitting its container(box). After driving another 300Km it started making noise again hitting the box so it was again adjusted by service center . I have purchased new bike and it is making noise as if it is 10 to 15 year old bike so i contacted Suzuki Motorcycle India Pvt. Ltd. where by they asked to contact service senter in Margao Goa. and there they removed the Drive chain and washed it and replaced the chain and adjusted the drive chain. However after another 250 Km the chain is making noise by hitting the box. I think the chain is faulty as normal life of drive cain is almost 20000 to 30000 Km. I have not use the bike for racing of quick acceleration also i was driving below 60Km/h mark for first 1000 Km as instructed by sales person nor techometer crossed 5000rpm normally as crossing it is indicated by blinking LED. Kindly help!