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Presta Valve: Proper Pump Attachment Thereto

All our bikes have Presta valves, which seem better suited for bike rims than the larger and more common automotive Schraeder valves:

Presta valve stem

Presta valve stem

For all these years, I’d been attaching the pump head so the obvious sealing ring near the nozzle opening lined up with the flat section adjacent to the valve core stem. The pump head never seemed stable on the stem, often leaked, and generally had a precarious hold:

Incorrect Presta pump head attachment

Incorrect Presta pump head attachment

Come to find out, more by accident than intention, that the correct way to attach the pump head involves ramming it all the way down onto the stem so that it can seal along the entire length of the threads. That’s nice and secure, doesn’t leak, and even looks like it should work perfectly:

Correct Presta pump head attachment

Correct Presta pump head attachment

I’d feel even more like a doof if I hadn’t learned to do it wrong by watching somebody else back in the day or if I haven’t observed many other people making exactly the same mistake. I think the fact that the short nozzles on the old-school Zéfal pumps I swore by back in my wedgie-bike days never got a good grip on Presta stems got me off to a bad start, but … dang do I feel stupid.

FWIW, the little tab sticking out under the latch handle makes up for a bit of slop in the valve head. When I got the pump, the Schraeder nozzle didn’t seal very well, either, and taking up a few mils of slack helped immeasurably. We don’t need that nozzle very often, but our bicycle touring guests frequently do; they know that they can top off a Schraeder-valved tube at any gas station or with any pump anywhere around the world.

[Update: I hate it when I misspell a word in the title…]

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  1. #1 by Aki on 2011-11-23 - 13:57

    “The Schrader valve (also called American valve)” (Wikipedia) Add umlauts: Schräder, and it sounds even more Germanish.

    A crashproof motorbike made in Germany.

  2. #2 by Sebastian Kuzminsky on 2011-11-23 - 21:17

    I like presta valves, and I carry a presta-to-schrader adapter in my tire patch kit for when a schrader pump is all I can find. The adapter costs about half a beer, weighs less than a pocket’s worth of pocket lint, and looks like it’ll last forever. And it works ok in a pinch!

    • #3 by Ed on 2011-11-24 - 07:56

      And it works ok in a pinch!

      My grossly excessive tool bag has one of those, too, Just In Case. I’ve never seen the reverse version that connects a Schrader stem to a Presta pump, which certainly indicates which problem is more likely.

      However, that adapter strikes me as one of those fiddly little things one would lose in the middle of a Kazakh sandstorm and not live to tell the tale…

  3. #4 by Aki on 2011-11-24 - 08:13

    How about the “Dunlop” valve? Still widely used in the countries where people came down from trees just lately i.e. Finland etc. .

    • #5 by Ed on 2011-11-24 - 20:34

      the “Dunlop” valve

      Good heavens! Talk about fiddly little parts, that thing has them all!

    • #6 by Frans on 2011-11-27 - 10:29

      That’d be the type I’ve got.

  4. #7 by eriq on 2011-12-13 - 09:13

    as for the fiddly things of the dunlop valve:
    schrader ones do have them too, but their valve core is screwed inside and you’ll need a special tool to remove it. Standard tool at car tire service stations for ages but the bike Industry just found out about it as no-tube tires came up: http://www.notubes.com/Core-Remover-Tool-P350.aspx
    There are replaceable valves/ cores tubes for presta too, but they become less available in modern ‘throw away’ times.
    As for the correct fitting of the pumps head:
    It depends on the head not the valve system, some do seal perfect with less valve threads, some do need to so many threads that the valve itself can be to short to be pumped correctly, especially with ‘V-type’ profile rims, it just depends on the pumps head, but in general: push it onto the valve until it goes no further.

    last not least:
    Strong advice to not screw the nut of the presta valve onto the rim. Its mostly useless just prevents the valve from slipping into the rim when pushing the pumps head onto the valve. But: Since most riders and shops don’t use talcum inside the tire to prevent the tube from wandering inside it, this nut is likely to cause a valve stripoff if tightened to the rim, as the tube will wander with tires that don’t fit that well. If you do need the nut anyway, screw it loosely so the valve can wander a bit. And use a good dash of talcum -or- baby powder to prevent the tire from wandering.
    god blog btw.

    • #8 by Ed on 2011-12-13 - 10:58

      schrader ones do have them too

      But those valve stems come out in one lump, rather than producing that handful of Dunlop parts!

      I’ve never seen a removable Presta valve, which is likely due to my habit of buying cheap-to-middlin’ tubes instead of fancy stuff.

      most riders and shops don’t use talcum inside the tire

      Some day I might have to buy another squeeze bottle of baby powder. The one I’ve been using all these years is getting nigh onto empty: those bed bug incidents put a real dent in my lifetime supply! [grin]

      After a couple of flats early in the season, we haven’t had any trouble accumulating 4000-ish miles on the bikes. This must be entirely due to Good Fortune, but it happened during my administration and I’ll take credit for it…

  5. #9 by eriq on 2011-12-16 - 04:41

    “This must be entirely due to Good Fortune, but it happened during my administration and I’ll take credit for it”

    That is the glorious return for the ones administrating – regardless of the sector, the one sentence: “no, it just works well, never noticed any problems” .
    cheers.

    • #10 by Ed on 2011-12-16 - 08:27

      And, of course, any bad events derive from the previous administration…

      [Note: I’ve been using that phrase for a very very long time and it was a political truism long before that.]