One thing I noticed was that sometimes with crappy tubes, the air wasn't actually going into the tires, it stays I'm the tube of the pump, which causes the pump to think it's at 100 psi , but when I go on the rollers the tires are going flat even though I'm only 130 pounds. If this is the case then it won't take many pumps to reach a high pressure. This doesn't happen with my other bike which has better and newer tubes. Hope this helps.