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What type of valve is this? (Tubular tyres)
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What type of a valve is this on my Tubular tyre? See attached photo.

I noticed the air pressure dropped a bit lately. I am using a JoeBlow pump, not sure how to pump this up.

Also, I usually clean my tyres and brake rim with soap and hot water after every bike ride and wipe them up with a rag. Is this a good habit?


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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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Looks like a Zipp valve extension to me: example

edit: or equivalent, that is more of an 'L' than a 'Z'
Last edited by: OddSlug: Feb 25, 18 9:43
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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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That is a valve extender.
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Re: What type of valve is this? (Tubular tyres) [jimatbeyond] [ In reply to ]
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jimatbeyond wrote:
That is a valve extender.

But how do I pump it?

I got a JoeBlow with Schrader and Presta valves.
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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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http://www.slowtwitch.com/...der_How-To_3007.html

You should just pump it as normal with the presta head of your pump. If air isn't going in then maybe the valve inside is stuck. But maybe explain a bit more about the problem. Losing pressure too quickly ot can't pump it up or something else?
Last edited by: OddSlug: Feb 25, 18 12:47
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Re: What type of valve is this? (Tubular tyres) [OddSlug] [ In reply to ]
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OddSlug wrote:
http://www.slowtwitch.com/...der_How-To_3007.html

You should just pump it as normal with the presta head of your pump. If air isn't going in then maybe the valve inside is stuck. But maybe explain a bit more about the problem. Losing pressure too quickly ot can't pump it up or something else?

I am not sure I understood any of it.

Seriously, what do I need to pump the thing?
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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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Does the presta head of your pump fit? If it fits does it pump up?
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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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I had a very similar valve extender on my zipp 808. You would place the pump head on the valve extender like any other valve and pump away. The valve is kept open so that air can be added to the tire, the air pressure from inside the tire keeps the valve closed ensuring you have air while riding. Now, because the valve is opened there is the slight chance it can wiggle loose and screw back down, closing the valve and making it impossible to pump up the tire. If you try to pump up the tire and air is not going in then you will have to remove the tire, remove the valve extender, re-open the valve, and then replace the extender and glue the tire back on.
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Re: What type of valve is this? (Tubular tyres) [tridude93] [ In reply to ]
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tridude93 wrote:
I had a very similar valve extender on my zipp 808. You would place the pump head on the valve extender like any other valve and pump away. The valve is kept open so that air can be added to the tire, the air pressure from inside the tire keeps the valve closed ensuring you have air while riding. Now, because the valve is opened there is the slight chance it can wiggle loose and screw back down, closing the valve and making it impossible to pump up the tire. If you try to pump up the tire and air is not going in then you will have to remove the tire, remove the valve extender, re-open the valve, and then replace the extender and glue the tire back on.

Thank you.

How can you tell that the valve is opened? How can I try to avoid the scenario you just described (closing of the valve) when pumping up the tyre?

As you can see I am running Tubular tyres. I have no idea about the glueing process. Any problem will have me running to a shop ($$$$).
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Re: What type of valve is this? (Tubular tyres) [tridude93] [ In reply to ]
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tridude93 wrote:
I had a very similar valve extender on my zipp 808. You would place the pump head on the valve extender like any other valve and pump away. The valve is kept open so that air can be added to the tire, the air pressure from inside the tire keeps the valve closed ensuring you have air while riding. Now, because the valve is opened there is the slight chance it can wiggle loose and screw back down, closing the valve and making it impossible to pump up the tire. If you try to pump up the tire and air is not going in then you will have to remove the tire, remove the valve extender, re-open the valve, and then replace the extender and glue the tire back on.

Ok so I was able to pump the tyre up with the regular Presta valve, like you said.

My JoeBlow pump is not showing me the tyre pressure when I am pumping, so it's hard to say but they do feel well inflated.

Any suggestions on how to avoid the scenario when I am pumping them up in the future?
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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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If you are not able to put air in the tire then the valve is closed. This happens when riding and the valve is jostled enough for it to screw back down. To prevent this, before attaching the valve extender you would open the valve the same way if you were pumping up a normal valve/tire. The trick to keep it open for more air to be added is to keep turning the valve cap (probably the wrong term) until it 'clicks and or stays in the open position. Basically once this is done the valve cap won't fall in allowing air to be added. Remember, the pressure in the tire will prevent air from escaping through the valve.
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Re: What type of valve is this? (Tubular tyres) [tridude93] [ In reply to ]
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tridude93 wrote:
If you are not able to put air in the tire then the valve is closed. This happens when riding and the valve is jostled enough for it to screw back down. To prevent this, before attaching the valve extender you would open the valve the same way if you were pumping up a normal valve/tire. The trick to keep it open for more air to be added is to keep turning the valve cap (probably the wrong term) until it 'clicks and or stays in the open position. Basically once this is done the valve cap won't fall in allowing air to be added. Remember, the pressure in the tire will prevent air from escaping through the valve.

I did manage to put air through the tyre as the Presta side of the pump worked. So it does seem to be open.

As you can see in the photo, there is no cap or any adjustment mechanism on the valve extender.
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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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As long as air is getting in then the valve then all is well. Sometimes readjusting or taking the pump head off and pumping a second time provides a better seal allowing you to read the amount of air put in the tire. Im sure you know this but all tires lose air after a while and if there are latex tubs in your tires then it will lose air much faster. But latex tubes are faster ;)
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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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gazoome wrote:
tridude93 wrote:
If you are not able to put air in the tire then the valve is closed. This happens when riding and the valve is jostled enough for it to screw back down. To prevent this, before attaching the valve extender you would open the valve the same way if you were pumping up a normal valve/tire. The trick to keep it open for more air to be added is to keep turning the valve cap (probably the wrong term) until it 'clicks and or stays in the open position. Basically once this is done the valve cap won't fall in allowing air to be added. Remember, the pressure in the tire will prevent air from escaping through the valve.

I did manage to put air through the tyre as the Presta side of the pump worked. So it does seem to be open.

As you can see in the photo, there is no cap or any adjustment mechanism on the valve extender.

The adjustment mechanism is on the valve attached to the actual tire, the extender is threaded over this original valve to provide more length for deep section wheels.
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Re: What type of valve is this? (Tubular tyres) [tridude93] [ In reply to ]
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tridude93 wrote:
As long as air is getting in then the valve then all is well. Sometimes readjusting or taking the pump head off and pumping a second time provides a better seal allowing you to read the amount of air put in the tire. Im sure you know this but all tires lose air after a while and if there are latex tubs in your tires then it will lose air much faster. But latex tubes are faster ;)

Thanks a lot for the advice!

I run Continental Gatorskin Sprinter Tubs on all my wheels. Not sure what kind of tube it is.
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Re: What type of valve is this? (Tubular tyres) [gazoome] [ In reply to ]
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gazoome wrote:
As you can see in the photo, there is no cap or any adjustment mechanism on the valve extender.


The tube/tire has a normal presta valve on it (you cannot see it right now). If you are familiar with a presta valve, it just has a little hand operated nut on the top. This opens and closes the valve. You unscrew it prior to pumping and then screw it down tight after pumping. When it is unscrewed, the valve is open. If you were to press on the valve you would let air out. When the nut is screwed down, the valve is closed and pressing on the valve would not let air out.

What you have is a zipp valve extender screwed onto your presta valve. The zipp valve extender is essentially a straw that screws on top of the presta valve. This extender however makes the presta valve inaccessible (it is in the middle of your rim anyway which is why you need the extender). Because you cannot access the presta valve and the nut on the top of it, when installing the zipp valve extender, the valve is left open. This is fine because nothing can bump it causing the valve to leak air. When you pump air into the zipp extender, the air pressure pushes the open valve down and the air flows into the tube. When you stop pumping, the air in the tube pushes the valve closed retaining the air in the tube.

It does not seem like you have any issues right now. You put your presta pump on the zipp valve extender, pump away, and air is going to the tube. If this is the case, great, keep doing what you are doing. What others have speculated is that the little nut on top of the presta valve "jiggled" closed. This can happen while riding over time. This is a problem because once it closes the only way to open it is to remove the tire/tube, remove the zipp valve extender, and re-open it.

I do not use this type of extender. I recommend the removable valve core type extender where you take out the valve core (the part with the little hand operated nut that opens and closes the valve), add a different type of extender, and reinstall the valve core on top of the extender. For this you would need a new extender and a tube with a removable valve ccore. With the zipp valve extender you have, I believe the recommendation is to essentially break the valve core open. You do this with a plyers by over unscrewing the little nut on the top till you hear it click. In doing so you will have essentially stripped the nut to a permanent open position. I have never done this so take that with a grain of salt. For all you know, this was done when the extender was initially installed.

Regardless, if air is going to the tube right now, there is no reason for you to make any changes. Pump the tube and enjoy your ride!
Last edited by: TennesseeJed: Feb 25, 18 14:52
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Re: What type of valve is this? (Tubular tyres) [tridude93] [ In reply to ]
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tridude93 wrote:
If you try to pump up the tire and air is not going in then you will have to remove the tire, remove the valve extender, re-open the valve, and then replace the extender and glue the tire back on.
No need to remove the tire. Just remove the valve extender (unscrew it), then turn it around and use the other end (the one that you normally takes the pump head) to open the valve. It's designed to grab onto the valve head so you can unscrew it. Then put the valve extender back the correct way and pump up your tire.

Oh and if your carbon rim is hollow (like on Hed Jets), be careful not to drop the valve extender inside the rim. If you do it' s a real PITA to fish it out through the valve hole (tip: use the curved end of a spoke).
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Re: What type of valve is this? (Tubular tyres) [TennesseeJed] [ In reply to ]
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"I run Continental Gatorskin Sprinter Tubs on all my wheels. Not sure what kind of tube it is."


Continental tires have butyl rubber inside of them.
Last edited by: jimatbeyond: Feb 26, 18 9:51
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