Thanks all for your advise. I realize I haven't lub the chain for quite a while, but mainly because I wasn't home and have left the bike outside on the street for most of two months. I probably should just replace the sprockets and chains then try to be discipline in lubricating them. For the brake discs, I have been considering swapping them for some wave discs which I heard are lighter. OTR even said I don't need two disc brakes, but I think I feel safer for having two.