I just bought a tire gauge, and tried to put up my tire to the recommended psi. It says the max. is 55 psi. But, when i pump up my tire to 25 psi, the thing is SOOOO tight. I'm scared i might pop the tube! I'm not sure how you guys get to the max... is it my tube or something? Even at the high psi, when i sit on it, it bulges a bit (my back tire) but my front tire is still stiff with no bulges. Should i just keep on pumping and pumping till i hit around 50 than stop?