Bicycle pumps and tyre valve connections.

Discussion in 'UK and Europe' started by Pyromancer, Jul 17, 2007.

  1. Pyromancer

    Pyromancer Guest

    Something (well, several somethings) I've wondered about for a while all
    seem to have come up at once in different threads:

    Pumps, and particularly the connections from them to the tyre valve.

    I've seen various recommendations for people to get track pumps, and
    always meant to ask just what a track pump was, from a recent thread I
    now know and can see why they're recommended! Planning to acquire one
    from a decent LBS soon - but I gather some of them also have those
    horrid "rubber ring" connectors that seem so common nowadays?

    In my youth, pumps came with a short length of hose which screwed onto
    both pump and valve. As long as you were careful not to let the pump
    end unscrew they were great, all the air you pumped went into the tyre
    and you could rest the end of the pump against the chainstays to make
    pumping easier.

    Then there seemed to be a change, and all of a sudden pumps had these
    built-in rubber contraptions which never seal properly to anything and
    force you to have the end of the pump bearing on the valve stem, rocking
    back and forth and trying to twist the wheel rim with every stroke, and
    leaking air all over the place unless you clamp them to the wheel with
    g-cramps.

    The Gazelle seems to have slightly different valves to either the
    traditional thin ones, or the car-tyre type we had in the days of
    Choppers (which were IMO the best as you could use garage air-lines or a
    car foot-pump to get some decent pressure in), so I'm not sure what kind
    of screw-on hose I need, but can anyone recommend a track pump that
    comes with screw-on hoses instead of those awful rubber monstrosities? I
    know it's not just that I've a bad pump as I've had loads over the years
    they were all the same in terms of wasted air and forces on the valve.

    NP: Queen - Bohemian Rhapsody
    --
    - DJ Pyromancer, Black Sheep, Leeds. <http://www.sheepish.net>
    Hard Rock, Leeds <http://www.hard-rock.org.uk>
    Broadband, Dialup, Domains = <http://www.wytches.net> = The UK's Pagan ISP!
    <http://www.inkubus-sukkubus.co.uk> <http://www.revival.stormshadow.com>
     
    Tags:


  2. Ace

    Ace Guest

    On Wed, 18 Jul 2007 04:32:38 +0100, Pyromancer
    <[email protected]> wrote:

    >In my youth, pumps came with a short length of hose which screwed onto
    >both pump and valve. As long as you were careful not to let the pump
    >end unscrew they were great, all the air you pumped went into the tyre
    >and you could rest the end of the pump against the chainstays to make
    >pumping easier.


    Did you ever notice how hot they got? This was due to the forced
    compression of air to get through the narrow bore of these tubes, and
    is indicative of just how inefficient they were. Modern pumps of
    nearly all varieties, even little 15cm mini-pumps, take a _lot_ less
    human effort for the same resulting pressures.

    >Then there seemed to be a change, and all of a sudden pumps had these
    >built-in rubber contraptions which never seal properly to anything and
    >force you to have the end of the pump bearing on the valve stem, rocking
    >back and forth and trying to twist the wheel rim with every stroke, and
    >leaking air all over the place unless you clamp them to the wheel with
    >g-cramps.


    I've been using various types of these for many years and have never
    had the problems you describe. Clearly, if you don't hold them
    properly they'll flap about, but by putting your 'front' hand around
    the pump and rim it's not difficult to form a form anchor, as it were.
     
  3. Mark McNeill

    Mark McNeill Guest

    Response to Pyromancer:
    > can anyone recommend a track pump that
    > comes with screw-on hoses instead of those awful rubber monstrosities? I
    > know it's not just that I've a bad pump as I've had loads over the years
    > they were all the same in terms of wasted air and forces on the valve.
    >
    > NP: Queen - Bohemian Rhapsody


    IME, any way the wind blows doesn't really matter to me. <dies>


    --
    Mark, UK
    "That's 'Party Line' by Abbreviated Sealing, and of course whenever I
    criticize the name of a band somebody will write in and say 'Of course
    what you don't realize is that it's a quote from Jean Jacques Pissoir's
    "Vortex - A Threnody"?', and it may well be so.
     
  4. Membrane

    Membrane Guest

    Pyromancer <[email protected]> wrote:

    >The Gazelle seems to have slightly different valves to either the
    >traditional thin ones, or the car-tyre type


    Gazelle Roadsters come with Woods aka Dunlop valves:
    http://www.sheldonbrown.com/gloss_w.html#woods

    Can't help on the pump question, I use the Gazelle supplied pump for
    mine (rubber ring type pump).

    --
    Membrane
     
  5. Paul Boyd

    Paul Boyd Guest

    Pyromancer said the following on 18/07/2007 04:32:

    > NP: Queen - Bohemian Rhapsody


    Wrong: Queen - Fat Bottomed Girls ;-)

    --
    Paul Boyd
    http://www.paul-boyd.co.uk/
     
  6. Ace <[email protected]> wrote:


    > Did you ever notice how hot they got? This was due to the forced
    > compression of air to get through the narrow bore of these tubes, and
    > is indicative of just how inefficient they were. Modern pumps of
    > nearly all varieties, even little 15cm mini-pumps, take a _lot_ less
    > human effort for the same resulting pressures.
    >


    I don't think the tube bore is an issue - the bore is at least as big
    as the valve bore, and there's no reason why it shouldn't be
    considerably bigger. The tube gets hot because the air has been
    compressed (which heats it up) and then passes through the tube.


    I agree with Pyromancer about the stick pumps, especially on a bike
    with mudguards where there's hardly any point that you can clamp your
    hand around the valve/pump/tyre. I think these are just made for
    cheapness - they don't need to add the little tube, so it saves
    a few pence, but because it's no longer possible to twirl the
    pump onto the screw thread they came up with the rubber washer
    bodge.

    Worst still are the universal fittings where a tube is fitted over the
    valve and then compressed by a clamp. Admittedly I've used mostly
    cheap pumps, but the expanding/compressing tube things do seem to be
    awful, taking a lot of effort to push on (yes, I do release it first!)
    - I managed to rip the inner tube with the valve on one attempt.

    I'm looking for a decent track pump to replace the one I got from
    Lidl. Or maybe just a better fitting for the valve, since that's
    really the only problem with it. Must be screw-on .. I don't see
    that the push-and-clamp type are any quicker or more convenient.

    -adrian
     
  7. Ace

    Ace Guest

    On Wed, 18 Jul 2007 10:27:35 +0100, Adrian Godwin
    <[email protected]> wrote:

    >Ace <[email protected]> wrote:
    >
    >
    >> Did you ever notice how hot they got? This was due to the forced
    >> compression of air to get through the narrow bore of these tubes, and
    >> is indicative of just how inefficient they were. Modern pumps of
    >> nearly all varieties, even little 15cm mini-pumps, take a _lot_ less
    >> human effort for the same resulting pressures.
    >>

    >
    >I don't think the tube bore is an issue - the bore is at least as big
    >as the valve bore,


    But it's much longer, so the amount of compression required to force
    it through the tube is _much_ greater than that needed for the valve
    stem, which , in any case, is actually wider than the inside bore of
    the old-fashioned tubes. Plus you've got the flexing effect of said
    tubes, which will lead to yet more pressure loss and heating.

    I learned this when I was about twelve, when I noticed that longer
    tubes took much more effort than shorter ones. The physics is not
    difficult, but it's not my area of expertise, so I'll leave it to
    someone who CBA.


    --
    Ace in Alsace - brucedotrogers a.t rochedotcom
    Ski Club of Great Britain http://www.skiclub.co.uk
    All opinions expressed are personal and in no way represent those of the Ski Club.
     
  8. Paulmouk

    Paulmouk Guest

    "Pyromancer" <[email protected]> wrote in message
    news:[email protected]
    >
    > Something (well, several somethings) I've wondered about for a while all
    > seem to have come up at once in different threads:
    >
    > Pumps, and particularly the connections from them to the tyre valve.
    >
    > I've seen various recommendations for people to get track pumps, and
    > always meant to ask just what a track pump was, from a recent thread I
    > now know and can see why they're recommended! Planning to acquire one
    > from a decent LBS soon - but I gather some of them also have those
    > horrid "rubber ring" connectors that seem so common nowadays?
    >
    > In my youth, pumps came with a short length of hose which screwed onto
    > both pump and valve. As long as you were careful not to let the pump
    > end unscrew they were great, all the air you pumped went into the tyre
    > and you could rest the end of the pump against the chainstays to make
    > pumping easier.
    >
    > Then there seemed to be a change, and all of a sudden pumps had these
    > built-in rubber contraptions which never seal properly to anything and
    > force you to have the end of the pump bearing on the valve stem, rocking
    > back and forth and trying to twist the wheel rim with every stroke, and
    > leaking air all over the place unless you clamp them to the wheel with
    > g-cramps.
    >
    > The Gazelle seems to have slightly different valves to either the
    > traditional thin ones, or the car-tyre type we had in the days of
    > Choppers (which were IMO the best as you could use garage air-lines or a
    > car foot-pump to get some decent pressure in), so I'm not sure what kind
    > of screw-on hose I need, but can anyone recommend a track pump that
    > comes with screw-on hoses instead of those awful rubber monstrosities? I
    > know it's not just that I've a bad pump as I've had loads over the years
    > they were all the same in terms of wasted air and forces on the valve.


    http://www.wiggle.co.uk/ProductDetail.aspx?Cat=cycle&ProdID=5360006664
    I bought one of these quite a few years ago and move it around to electric
    pumps, foot pumps and an old large dia track pump (originally from a Lada
    car tool kit).
    It came with a variety of screw fittings for use at the pump end, so it will
    fit quite a few.
    Paul.

    It's quite the most useful accessory I've ever bought.
     
  9. Clive George

    Clive George Guest

    "Pyromancer" <[email protected]> wrote in message
    news:[email protected]

    > so I'm not sure what kind
    > of screw-on hose I need, but can anyone recommend a track pump that
    > comes with screw-on hoses instead of those awful rubber monstrosities? I
    > know it's not just that I've a bad pump as I've had loads over the years
    > they were all the same in terms of wasted air and forces on the valve.


    Having had loads of pumps over the pump doesn't necessarily mean they
    weren't all bad. Have you for example tried a zefal HPX or a Topeah morph
    pump? Neither have a screw on hose, both work very well IME.

    For a track pump, get one with a head suitable for the valve (eg presta)
    rather than one which has a car-type valve and an adapter. Topeak ones work
    IME - eg the twinhead ones. Again not screw-on, but that doesn't seem to be
    a problem.

    If you can't make them work with your woods valves, you could always change
    the tubes to prestas - you may well end up doing that eventually anyway due
    to availability.

    cheers,
    clive
     
  10. vernon

    vernon Guest

    "Ace" <[email protected]> wrote in message
    news:[email protected]
    > On Wed, 18 Jul 2007 10:27:35 +0100, Adrian Godwin
    > <[email protected]> wrote:
    >
    >>Ace <[email protected]> wrote:
    >>
    >>
    >>> Did you ever notice how hot they got? This was due to the forced
    >>> compression of air to get through the narrow bore of these tubes, and
    >>> is indicative of just how inefficient they were. Modern pumps of
    >>> nearly all varieties, even little 15cm mini-pumps, take a _lot_ less
    >>> human effort for the same resulting pressures.
    >>>

    >>
    >>I don't think the tube bore is an issue - the bore is at least as big
    >>as the valve bore,

    >
    > But it's much longer, so the amount of compression required to force
    > it through the tube is _much_ greater than that needed for the valve
    > stem, which , in any case, is actually wider than the inside bore of
    > the old-fashioned tubes. Plus you've got the flexing effect of said
    > tubes, which will lead to yet more pressure loss and heating.
    >
    > I learned this when I was about twelve, when I noticed that longer
    > tubes took much more effort than shorter ones. The physics is not
    > difficult, but it's not my area of expertise, so I'll leave it to
    > someone who CBA.
    >

    I'm afraid that you have been misinformed the heating effect is almost
    independent of the bore of the tube i.e. for normal lengths encountered
    there is not much variation in pressure needed to force air through the
    connector. The gain in heat is purely due to the gain in energy of the air
    molecules. When compressed they gain in kinetic energy which is then
    converted converted into heat energy. The flexing of the connector does
    nothing to affect the heating effect of compressing the air. A pressure
    loss would lead to a cooling effect.

    Trust me, I'm an ex-physics teacher.
     
  11. vernon

    vernon Guest

    "Clive George" <[email protected]> wrote in message
    news:[email protected]
    > "Pyromancer" <[email protected]> wrote in message
    > news:[email protected]
    >
    > If you can't make them work with your woods valves, you could always
    > change the tubes to prestas - you may well end up doing that eventually
    > anyway due to availability.
    >
    > cheers,
    > clive

    Clive, you've beaten me to it. I too think that Pyromancer's bike has woods
    valves and that a change of tubes would be an easy solution to the inflation
    problem. I think though, that I have seen bike pumps with woods connectors
    in Wilkinsons.
     
  12. On Jul 18, 4:32 am, Pyromancer <[email protected]>
    wrote:
    > I've seen various recommendations for people to get track pumps, and
    > always meant to ask just what a track pump was, from a recent thread I
    > now know and can see why they're recommended! Planning to acquire one
    > from a decent LBS soon - but I gather some of them also have those
    > horrid "rubber ring" connectors that seem so common nowadays?


    Decent ones of these are fine. Most track pumps have a flip up thumb
    lever that clamps the head onto the valve. Some have a schraeder haed
    and a screw on adapter that sizes up presta valves to fit

    > The Gazelle seems to have slightly different valves to either the
    > traditional thin ones, or the car-tyre type we had in the days of
    > Choppers (which were IMO the best as you could use garage air-lines or a
    > car foot-pump to get some decent pressure in), so I'm not sure what kind
    > of screw-on hose I need, but can anyone recommend a track pump that
    > comes with screw-on hoses instead of those awful rubber monstrosities? I
    > know it's not just that I've a bad pump as I've had loads over the years
    > they were all the same in terms of wasted air and forces on the valve.


    it will be a woods (or dunlop) valve. Despite being shit, they are
    popular on the continent. They work adequately if sealed with some
    spit. They take the same fittings as presta valves

    hth
    james
     
  13. Rob Morley

    Rob Morley Guest

    In article <[email protected]>, Pyromancer
    [email protected] says...
    >
    > Something (well, several somethings) I've wondered about for a while all
    > seem to have come up at once in different threads:
    >
    > Pumps, and particularly the connections from them to the tyre valve.
    >
    > I've seen various recommendations for people to get track pumps, and
    > always meant to ask just what a track pump was, from a recent thread I
    > now know and can see why they're recommended! Planning to acquire one
    > from a decent LBS soon - but I gather some of them also have those
    > horrid "rubber ring" connectors that seem so common nowadays?
    >
    > In my youth, pumps came with a short length of hose which screwed onto
    > both pump and valve. As long as you were careful not to let the pump
    > end unscrew they were great, all the air you pumped went into the tyre
    > and you could rest the end of the pump against the chainstays to make
    > pumping easier.


    Actually some of the air that you compressed stayed in the hose on each
    stroke, so that was effort wasted. The push-on pumps ahift nearly all
    the air into the tyre with each stroke, so are more efficient.
    >
    > Then there seemed to be a change, and all of a sudden pumps had these
    > built-in rubber contraptions which never seal properly to anything and
    > force you to have the end of the pump bearing on the valve stem, rocking
    > back and forth and trying to twist the wheel rim with every stroke, and
    > leaking air all over the place unless you clamp them to the wheel with
    > g-cramps.


    I think maybe you need to work on your technique - push-fit pumps are
    fine as long as you use them properly.
    >
    > The Gazelle seems to have slightly different valves to either the
    > traditional thin ones, or the car-tyre type we had in the days of
    > Choppers (which were IMO the best as you could use garage air-lines or a
    > car foot-pump to get some decent pressure in)


    Car foot pumps aren't much good for high pressure bike tyres, they're
    designed for a highish-volume lowish-pressure application.

    > so I'm not sure what kind
    > of screw-on hose I need, but can anyone recommend a track pump that
    > comes with screw-on hoses instead of those awful rubber monstrosities? I
    > know it's not just that I've a bad pump as I've had loads over the years
    > they were all the same in terms of wasted air and forces on the valve.
    >

    If you don't have Schraeder or Presta valves then you probably have
    Woods valves - these have the same connecting thread as a Presta and the
    same stem size as a Schraeder. The easy solution is to get a Schraeder
    adaptor (a little knurled brass collar with a Presta/Woods thread inside
    and a Schraeder thread outside) and use a Schraeder pump.
     
  14. Dicicco

    Dicicco New Member

    Joined:
    Apr 29, 2019
    Messages:
    3
    Likes Received:
    0
    The screw on pumps unscrew my Presta valve so I thighten the knurl nut on the valve but it seems to damage the valve in that it no longer holds air. Did I just over tighten? But will the screw in pump then unscrew my valve when I try to detach the pump from the valve if it’s not really tight??/
     
  15. dabac

    dabac Well-Known Member

    Joined:
    Sep 16, 2003
    Messages:
    2,182
    Likes Received:
    111
    You’re doing it wrong.
    Some Presta valves have removeable cores. It seems like yours are that kind. They can be identified by the tool flats that are machined into the threads for the valve cap/screw-on pump.
    If your valve cores are coming unstuck, this is where you engage a tool to tighten the core to the valve stem.
    You DON’T do that with the small knurled nut. The small knurled nut is ONLY to keep the valve shut.
    If you find this difficult, switch to tubes w/o removable cores.
    It is POSSIBLE to overtighten the knurled nut to the point where it snaps the moving part of the valve that actually controls air movement in/out. If you do, that part falls off into the tube and is lost.
    Since it seems like you have removeable cores, simply replace the core and you should be able to keep using the tube.
     
  16. Dicicco

    Dicicco New Member

    Joined:
    Apr 29, 2019
    Messages:
    3
    Likes Received:
    0
    Thank you very much this is so helpful. I was referring to the "core" and mistakenly called it the knurled nut since I did not know what the "knurled nut " was. Now I do, thanks again.

    I must have over tightened it. If I just make it snug I will see if it doe s not come unscrewed. This seems a little tricky.
     
  17. dabac

    dabac Well-Known Member

    Joined:
    Sep 16, 2003
    Messages:
    2,182
    Likes Received:
    111
    I can’t see how it’d be possible to overtighten the core unless you’ve used a tool. For its size, it’s quite robust. All that could possibly happen is that you strip the threads either in the valve stem or on the core. If it’s the stem threads that are damaged, the tube is probably beyond repair.
     
  18. Dicicco

    Dicicco New Member

    Joined:
    Apr 29, 2019
    Messages:
    3
    Likes Received:
    0
    Sure did, a needle nose pliers...When I tried hand tightening the pump would unscrew the valve every time..
     
    #18 Dicicco, Apr 30, 2019
    Last edited: Apr 30, 2019
Loading...
Loading...