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Help.. cant pump air in tubular through valve extender
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I think my presta valve is shut... I cant pump air through the valve extender, and since its tubular I cant undo the tire to see whats going on.. It's hooked to a zipp 404 so I the deep rim is preventing me from fixing the issue too..

Any ideas or do I have to rip open the tubular tire?
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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Does the tire have any air in it right now? Sometimes I've have to let some out before trying to fill it again.

jaretj
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Re: Help.. cant pump air in tubular through valve extender [jaretj] [ In reply to ]
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Its completely deflated
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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Is it a "foreskin" style extender or the type with removable valve mounted externally?



Dick Chartier

"Get up on your bike" Luka Bloom
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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You can always twist off the valve exender and then rig up something to go in there and twist the valve open. I've done this using another extender that is just bigger than the valve.

Also sometimes the valved just get stuck. if you pull off the extender and push the valve down that could do the trick as well.

This is your life, and it's ending one minute at a time. - Fight Club
Industry Brat.
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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Did you put any sealant in that has clogged it?
If it is just the valve that has shut, use a straight pin to stick in the valve extender to turn the presta valve (be sure you figure out which way you want to turn the valve before you do it). Most of the time this will work,
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Re: Help.. cant pump air in tubular through valve extender [Ti T'war] [ In reply to ]
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Ti T'war wrote:
You can always twist off the valve exender and then rig up something to go in there and twist the valve open. I've done this using another extender that is just bigger than the valve.

Also sometimes the valved just get stuck. if you pull off the extender and push the valve down that could do the trick as well.

Yes, thats what Im trying to do.. But how do I twist the valve up? The hole in the zipp 404 is very small.. I tried to fit twizers in there but the hole is too small to grip the twist thing.
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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125mph wrote:
I think my presta valve is shut... I cant pump air through the valve extender, and since its tubular I cant undo the tire to see whats going on.. It's hooked to a zipp 404 so I the deep rim is preventing me from fixing the issue too..

Any ideas or do I have to rip open the tubular tire?

You're basically screwed and will likely have to remount the tire at which time you should go to some removable valve core or in-line extenders to avoid this in the future.

You might get lucky and be able to remove the extender from the outside and carefully open the valve if there's enough exposed but getting a good seal on the extender when you screw it back on will be a challenge. I helped a team mate with just this problem a while ago and he was able to pull it off by replacing his Zipp external extender with an aftermarket (Topeak or Problem Solvers, I don't remember which one) that had a small o-ring built in that allowed him to get a good seal without having to wrap teflon tape on the inaccessible threads buried down in the rim.

-Dave
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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Tubes with removable valve cores.

Go get them. You'll never have to deal with this crap ever again.

Also, how deep are your wheels? If up to 60mm, you can run 80mm stems and won't need extenders at all. If you got 808s well then it's tubes with removable cores and appropriate extenders. That's what I run and it's awesome. (I carry a traditional extender in my flat repair kit though.... just in case I borrow a tube with non-removable cores from someone else.)
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Re: Help.. cant pump air in tubular through valve extender [Dave_Ryan] [ In reply to ]
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topeak extender has end that lets you open or close what it is attached to
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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This has happened to me (Sunday at my race) I take out the extender and use a wooden kebob skewer to un screw the the presta thingie. Patience, it takes.

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Re: Help.. cant pump air in tubular through valve extender [jw67] [ In reply to ]
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jw67 wrote:
This has happened to me (Sunday at my race) I take out the extender and use a wooden kebob skewer to un screw the the presta thingie. Patience, it takes.

This.

For several seasons, I've have a sticky valve on my front 808 (tubular)... I have to jimmy it open far more often than not.

I took a small old L-shaped allen wrench, scuffed up the long end with some rough emery cloth, then apllied a dab of some sort of soft glue goop I had laying around in the basement - this give the tip a bit more grip. A wooden kebob skewer is a great idea - I'll try that out next time!

When the valve sticks, just shove in the wrench/kebob, press down, and twist it CCW a few spins - I've always been able to eventually get it to "catch" and free the valve.

Not the greatest thing to deal with, but not the worst... Just don't forget to pack the "device" in your flat kit on race day :)

Good luck, Chris

Do not taunt Happy Fun Ball
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Re: Help.. cant pump air in tubular through valve extender [jw67] [ In reply to ]
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jw67 wrote:
This has happened to me (Sunday at my race) I take out the extender and use a wooden kebob skewer to un screw the the presta thingie. Patience, it takes.

I used a baby screw driver to twist the presta all the way up... but now all the air I pump in fizzes out.. I think the seal is not tight...
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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it is difficult to apply teflon tape when valve is in the hole.

if you pump fast enough you can still inflate it :)
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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At the end of the day, you'll likely find that the presta valve is a bit bent and is rubbing against the extender holding it open and/or closed. This will frustrate you until you pull it off and fix or replace it. Better to pull it apart now than to have a problem on race morning.

My choice is the Vittoria system where you can swap out various length valve stems that have the valve on the end.

May go without saying, but make sure you keep the right length valve on your spare.
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Re: Help.. cant pump air in tubular through valve extender [BookemDanO] [ In reply to ]
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Ripped off the tire.. using the valve extenders that you use with removal cores now... sux!!!
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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This happens to me all the time. I use a Zipp valve extender and turn it 180 degrees and use the other end to twist the valve open (i.e. the end you normally attach the pump to). I also use teflon tape on the valve thread bit to make sure I always have a good seal when I use the extender. I use Vittoria tires but use valve stems that are not as long as my rim is deep figuring I don't need to have something sticking out the rim if I don't need to. Of course, using a valve stem longer than the depth of your rim is more convenient though.
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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I never trusted those kind of extenders. Thanks for diving on that grenade and proving my suspicions confirmed. These work like champs:


/kj

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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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Removable valves (not just extenders and cores) are great, but you can only use them on certain Vittoria Tyres



http://www.vittoria.com/product/accessories/
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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This happened to me once, on my Easton EC90TT rims, and I made an 'instrument' to open the presta valve through the valve extender.

Took an old spoke, and cut a small slit in it to 'grab' the valve at the bottom of the extender and twist to open it up. Works beautifully. :)

I'm a dentist, and cut the slit in the spoke using a high speed handpiece and a 1/2 mm round carbide bur. Do you have any buddies who are dentists or have access to dental equipment?? There may be other ways to cut a small slit into an old spoke using household tools, but this was what I came up for cutting such a small slit into a small spoke. :) Ended up making some for a few bike mechanics after they found out about this, and have had buddies use this little 'instrument' when they have come into this same predicament.

With that being said, I switched over to using the extenders where the core is placed at the end (what others mentioned on this thread) after this situation. :)

pic (close up of the end of a cut spoke):



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Re: Help.. cant pump air in tubular through valve extender [toothpick] [ In reply to ]
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That's impressive :)
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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TRY THIS!

Use the valve extender itself as the tool to loosen/open the valve.

Remove valve extender (Zipp, I assume); flip extender upside-down; insert into valve hole making contact squarely with presta-valve knurled nut; using slight pressure against the nut, turn counter-clockwise loosening the knurled nut; this should open the presta valve. Gently re-install valve extender as designed, tighten. Inflate tire.

A temporary fix until tire replacement/re-glue, but it has worked for me dozens of times.
Last edited by: Brushman: Mar 27, 13 5:15
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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ive had a valve just close a bit....i used a longer allen wrench(or something really thin) to stick up there to open the valve a bit. Then it aired up fine. If that doesnt work, you are gonna have to do what all these others said.


Rattlesnake Blake
With the "Venom Enom"
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Re: Help.. cant pump air in tubular through valve extender [Brushman] [ In reply to ]
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Quote:
Use the valve extender itself as the tool to loosen/open the valve.


This has definitely gotten me out of a jam before. If you aren't anticipating having the valve close up on you the valve extender itself is pretty much the only thing you're guaranteed to have around that even has a prayer of temporarily fixing the problem.

Pro tip (if it hasn't been mentioned already): if you are using a tire that doesn't have a removable valve core, unscrew the tiny nut all the way and put some thread locking compound on it (i.e loctite). If you don't have loctite you can just crush it with some pliers. Think about it...you want it to stay open. Do what you have to to make it stay open permanently--it will save you a lot of heartache on race morning (because per Murphy's law that will most likely be the first time this problem would otherwise reveal itself to you).

edit to add emphasis.

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Last edited by: ZackCapets: Mar 27, 13 6:29
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Re: Help.. cant pump air in tubular through valve extender [125mph] [ In reply to ]
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I twist my valve core about 1/2 turn too far open with pliers to lock it in place. 25 + years on tubies and have yet to have any kind of valve issue. The LBS where I worked in college some crusty old dude showed me that when I was learning tubie mounting.
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