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  1.  
    I've gotten a lots of flats from valves pulling through lately. It's a rabid pain in my ass. So I invested nearly thirty seconds into the problem and came up with this:

    That nearly useless nut that comes on the valve stem? Don't screw it on the outside of the rim. Screw it on the *inside*. That way, when you pull the pump head off, you're not pulling the rubber against the edges of the valve hole. You're pulling the nut, which is threaded onto the valve.

    If you want, you can screw another one on the outside so you don't push it in when you stick the pump on, which might be a little easier. Just make sure you've got really long valve stems.
  2.  
    Yay
  3.  
    Have you been having this problem too?

    I think I've been because I've been making sure my tire pressure's always up, which means attaching and detaching the pump every day.
  4.  
    I did that by accident once, never bothered to change it out and eventually ran over the spring from a clothespin. Upon removing my tube, an LBS mechanic told me that the valve collar can eventually wear a hole in the tube if installed inside the rim. I don't know how likely such a scenario is, but I thought I'd mention it. I do like the idea of using one on both sides.
    I'm curious Joshua, how are you managing so many pull throughs? I don't think I've ever had that happen to me. What do you use for pumpage?
    • CommentAuthorgreg
    • CommentTimeSep 4th 2009
     
    Maybe you need a pump that doesn't require as much violence to keep attached. The Joe Blow pump I have doesn't put that much pressure on the valve stem after the lever is released
    • CommentAuthorquidose
    • CommentTimeSep 4th 2009
     
    how is there any pulling happening when you take the pump head off? is the pump head somehow getting stuck on the valve stem when you're trying to take it off, thereby causing you all of these pull throughs? i also always like to keep my tire pressure up, putting in a little air before almost every ride, but neither hand pumps nor floor pumps face any resistance when being pulled from the valve stem. it seems more likely that you'd get a pinch flat of sorts if your tire pressure was too low when you tried to shove the pump head On to the valve stem, which is why the the threaded nut is intended to be on the outside of the rim (i.e. to prevent the valve stem from pushing into the tube when attaching the pump head). if i'm off track, feel free to redirect me, i'm just not sure how this could be happening.
    • CommentAuthorSkidMark
    • CommentTimeSep 4th 2009
     
    Maybe not be such a ham-fisted wrench monkey?

    A flat washer for a 6mm bolt would be a more realistic "solution". That nut is too thick and the outside is knurled, so when the tube deforms around it, it will eventually wear and blow out.
  5.  
    Skid, washers aren't threaded. And the amount of deformation is not substantially different from that around the bead. You may have noticed that tubes are stretchy. They can deform. It's not a problem. Pump one up outside of a tire and you'll see just how much.

    My pump sucks. It's a Blackburn from a couple of years ago. There's not much to like about it, but it's the one I have and, until I start getting more clients again, I'm not going to replace something that's minimally functional.

    What's odd is that twice now, the valve has crapped out during wholly unexciting activities. Once, riding down the street (fortunately, just before the turn into my driveway), and another time while it was just hanging there. I thought it might be a ragged edge on the valve hole, but it feels round and soft to my fingers, particularly given the presence of the tape.

    I think it's very likely that the best long-term solution is a new pump. Joe Blow has been recommended to me often, so I'll probably go that way when my clients are less spooked.
  6.  
    normally i would just say bleh i don't need those on either side. but as ive learned going going no rim strips, to electrical tape, to 50 cent a piece rubber to the canvas plastic adhesive rim strips, there is probably a reason that these products. and to add on to greg i love my rav-x blow-x pump decent price too
    • CommentAuthorgreg
    • CommentTimeSep 4th 2009
     
    Joe Blow Sport, $30 and worked fine for me on my stable of bikes

    • CommentAuthorRuffinit
    • CommentTimeSep 4th 2009
     
    Guys,
    The reason for he pull throughs is that IF you use the collar nut on the valve stem and you tighten it up each time it gets loose, what you end up doing is cutting the tube by pulling it against the inside of your rim (high pressure will do the rest). It's not from your pump. Most experienced riders and ALL racers know to throw that damn nut away as soon as you pull your new tube out of it's box. This is a very common occurance with presta valves (and very rare with schraders). IF you are pumping up your tire and the stem pushes in, just push back from the tire side with your thumb. The proper way to use a frame pump is to hold the tire/wheel and pump head with one hand while pumping with the other.
    And DON'T put it on the inside of the rim as it will cause abrasion to the tube if you are running high pressure. If you've ever had to replace rim strip/tape because the nipples have worn through it, you know what I mean. Same principle.
    • CommentAuthorSkidMark
    • CommentTimeSep 4th 2009
     
    Posted By: Joshua A.C. NewmanSkid, washers aren't threaded. And the amount of deformation is not substantially different from that around the bead. You may have noticed that tubes are stretchy. They can deform. It's not a problem. Pump one up outside of a tire and you'll see just how much.


    Do whatever you want. I'll bring you flowers when your 120 psi front tire blows out.



    A 6mm washer would fit over the threads, a presta stem is m6 x .8. It would be held in place between the rim and the tube. It would work the same as the stepped washers they make when you are using presta tubes on a rim drilled for shraeder.

    All you need to do is not use tools like you are a badly trained orangutan, and you'll stop pulling valve stem off tubes.
  7.  
    Read the post, dude. My 120 psi front blew out the other day. That's the problem I'm trying to solve. Fitting over the threads is the *problem*. A washer puts the pressure at the base of the valve stem. A nut puts the pressure on the stem itself.

    I shoved some grease into my pump head today. It made it go on and off much more easily. I suspect that's the issue and the real solution.

    Ruffinit, you point something out: I didn't have this problem for a long time. I started having it recently when I started using the nuts again.

    SkidMark thought it would be a good idea to say:
    All you need to do is not use tools like you are a badly trained orangutan, and you'll stop pulling valve stem off tubes.


    I don't know what your problem is, but you can keep it to yourself.
  8.  
    Ruffinit nailed the problem and the solution here really. The secret is don't yank the pump head off without holding onto your valve stem with the other hand to keep it in place. Now personally I use tubes with smooth stems so the pump head just pops right off with little effort but if you're using tubes with threaded stems you may need to just use your left hand to keep the thing in place while gently removing the pump head.
    It seems like all this extra effort you're going through (grease on the stem, putting the locking nut on backward, etc..) is kind of a waste of time. Just be a tad more cautious with the thing and it'll be fine.
    • CommentAuthorscruggle
    • CommentTimeSep 5th 2009
     
    Posted By: Joshua A.C. NewmanA washer puts the pressure at the base of the valve stem. A nut puts the pressure on the stem itself.


    How does the nut put any pressure on the stem? The point of the nut is to help keep the valve stem from dropping through the rim when putting the pump head on and during inflation. It's never for bolting the tube and the rim together tightly. As you inflate the tube, it's fine to loosen the nut. After tube/tire installation, the nut should be just barely snugged up against the rim to stop it from vibrating loose. Unless someone knows better than me, anyway.
  9.  
    I've never used the "nut" on any of my wheels/tires and have never had a problem.
  10.  
    fuck those stupid valve nuts ! the only use I ever found for them is putting one on the inside when you have to use a presta tube on a shrader rim.If you don't want to spend the cash for a new pump try putting a little silicone grease on the rubber seal in the pump head . Don't use petroleum based grease ,it will dissolve the rubber. check for burs around the valve hole and sand smooth if needed.cut a little circle of cloth rim tape and slip it over the valve of your tube (sticky side down ,so it sticks to your tube)before you install it.if you are not useing cloth rim tape on your wheels START.it helps prevent flats more than people my think.
    • CommentAuthorheadydude
    • CommentTimeSep 6th 2009
     
    why would you ever think putting a nut INSIDE the rim was a good idea? that = way more flats than you were getting than before when you were just ripping the valve off.
  11.  
    Ruffinit, thanks.

    Jaiden, I prefer smooth valves, but can't seem to find them and can't remember what brand they were. What do you like?
  12.  
    Posted By: Joshua A.C. NewmanRuffinit, thanks.

    Jaiden, I prefer smooth valves, but can't seem to find them and can't remember what brand they were. What do you like?


    I've been using the Novara Light Long Valves (REI's house brand, they're down the street from my house). They work. Someone at the shop told me that because they were light they were more prone to punctures. While this may be true I've got Conti Gators front and rear so if something's getting through those it's getting through my tube no matter how thick or light it is.
 
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