Pffffffffft... Tyre pressures

xloly
xloly Posts: 140
edited April 2010 in Road beginners
When inflating a tyre using my Bonty Track pump with PSI gauge if I reach the desired PSI then remove the pump from the valve the valve lets out a loud Pffffffft....
Is there a way of avoiding this so I get a more accurate level of pressure in my tyres? Currently, I'm over inflating by about 10PSI in the hope that is what I'm letting out.
If that makes any sense?

Help appreicated.

Comments

  • balthazar
    balthazar Posts: 1,565
    That air is let out from the pump hose itself, which is at the same pressure as the tyre when connected. The loss from the tyre itself is insignificant.
  • pbt150
    pbt150 Posts: 316
    If it's only short then I wouldn't worry about it, both my track pump and mini-pump do this a bit, just a short hiss as you remove the pump. Inflate to the pressure you want, there won't be a noticeable drop.

    Don't forget there is also some compressed air in the chambers inside the pump, that will be released as you remove the valve from the pump. Some of the air will be coming from here too.
    FTT
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  • xloly
    xloly Posts: 140
    Oh, result! I was loosing so much sleep over this! :D
  • dennisn
    dennisn Posts: 10,601
    balthazar wrote:
    That air is let out from the pump hose itself, which is at the same pressure as the tyre when connected. The loss from the tyre itself is insignificant.

    +1

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