No, the hanger is not bent, I am 100% sure of that. It is a brand new derailleur and I checked, the alignment of the hanger is straight. I thought it might be the pulley or hanger problem because the faster I peddle, the higher frequency of noise i hear. The noise doesnt really get louder but it click more faster. Now that i checked my bike more, I think Fixer might be right about the chain is too short. The chain gets pretty tight when im at the biggest cog and biggest chainring. Although, when loosen the pulleys screw quarter of a turn , the noise gets lower. I dont think its a good idea to loosen the screw tho but it seem to help my problem. Any idea guys?