Bicycle hand pump pressure gauge Today I got my new bike pump. It is a two-way pump with pressure gauge, up to 100 psi, that I bought cheaply over the internet. When I tried to pump up my tire (Schrader valve) it seemed to be working, I mean, it pumped my tire. But the problem is that the gauge shows 20-25 psi even if I pump more and more until I can hardly squeeze the tire. Also, when I let the air out, it shows less than 10 psi. So the range is 5-25 psi let's say... On the other hand, when I place my thumb on the pump valve and squeeze the pump, it shows 30-40 even 50 psi (I can't hold it to higher psi range). 

What can the problem be? Is it possible I am not putting the pump in the right position when I am pumping the tires?

Thank you in advance!
I have a Topeak "Road Morph" mini pump on my bike, and the pressure gauge on that is at best a distraction. The display is a bit of plastic sliding in a tube, so there's a lot of friction and that makes the pressure reading unreliable. It can stick anywhere, but usually it reads low, like yours does. That makes it useless for anything other than "is there air in my tyre", which I can answer more easily by squeezing the tyre.




So it's likely that the reason you're having problems is that your pump is a cheap version of mine, and it works even less well than mine

The effective pressure gauges that I've seen are all dial gauges, and there are not many mini pumps that have those. Normally they're found on floor pumps like this: