I have a creak in my bike. It is a mtb aluminium frame and whenever i pedal hard or out of the saddle there is a creak. I recently overhauled the entire bike with new cables, greased all pivots and gears, cleaned the chain and then lubed it up. Checked saddle checked and reinstalled bb with plumbers tape. It worked fine for about a month and then it started to creak again. I use the bike on the road for the majority of its life. I have been riding the frame for a few years and maybe its time to get a new frame.