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Just ordered some deep dish wheels and wondering how the valve extenders work. Will the presta tip screw itself down when attaching the valve extender or do I need tubes with removable cores (or tubes with LONG stems)?

I have quite a stockpile of short, non-removable-core tubes. Assuming I DO need removable cores because attaching the extender will close the presta valve, is there a workaround for this? Like crimping the tip with it open to keep it from screwing it down? Breaking the tip off once its open?

I always carry a spare tube but if I were to flat that one too, just trying to think of how I'd address the situation if I was out in the wild and had to "bum" a tube from someone else and it didn't have a removable core. Hope that all makes sense.
 

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Never used them on presta, but have on schrader years ago (mtb). If they work the same then you'd just undo the valve then screw the extender on, then the extender when you use it just presses down on the normal valve to work. Well thats how the valve adapters seem to work presta->schrader for different pump heads. Could be completely wrong.
 

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With non removable core valves you just unscrew the top part and leave it loose while you screw the valve extender over the top of it. The valve extender shouldn't catch on it and do it up again.

Personally I like using tubes with long valve stems (including my spare regardless of which wheels I'm running, deep or shallow profile etc), but carry a valve extender with me in case I need to bum a tube off someone in an emergency
 

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With non removable core valves you just unscrew the top part and leave it loose while you screw the valve extender over the top of it. The valve extender shouldn't catch on it and do it up again.

Personally I like using tubes with long valve stems (including my spare regardless of which wheels I'm running, deep or shallow profile etc), but carry a valve extender with me in case I need to bum a tube off someone in an emergency
this. plus you'll likely need some plummer's tape to wrap around the valve threads to make the seal tight. Mavic used to sell valve extenders that included small o-rings but I haven't been able to find these in awhile.
 

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Just ordered some deep dish pizzas and wondering how the valve extenders work. Will the presta tip screw itself down when attaching the valve extender or do I need tubes with removable cores (or tubes with LONG stems)?

I have quite a stockpile of short, non-removable-core tubes. Assuming I DO need removable cores because attaching the extender will close the presta valve, is there a workaround for this? Like crimping the tip with it open to keep it from screwing it down? Breaking the tip off once its open?

I always carry a spare tube but if I were to flat that one too, just trying to think of how I'd address the situation if I was out in the wild and had to "bum" a tube from someone else and it didn't have a removable core. Hope that all makes sense.
ftfy...


'Dish' is how the rim is centered over the hub. 'Section' describes the rim shape.

Tubes w/ cores that can be removed are the best. If you can't get those I'd recommend opening the valve all the way then forcing it a bit more so it will stay or even crimping it a bit w/ pliers.

And posting in the correct section of the forum is always good too.
 

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Just ordered some deep dish wheels and wondering how the valve extenders work. Will the presta tip screw itself down when attaching the valve extender or do I need tubes with removable cores (or tubes with LONG stems)?

I have quite a stockpile of short, non-removable-core tubes. Assuming I DO need removable cores because attaching the extender will close the presta valve, is there a workaround for this? Like crimping the tip with it open to keep it from screwing it down? Breaking the tip off once its open?
I've had them vibrate closed on me. I put a dab of Loctite on the valve nut threads to prevent it.

I always carry a spare tube but if I were to flat that one too, just trying to think of how I'd address the situation if I was out in the wild and had to "bum" a tube from someone else and it didn't have a removable core. Hope that all makes sense.
I carry a spare with a long stem so I don't have to bother with the extender. I also carry an extender with o-ring in case I have to borrow a tube.
You could put a few wraps of Teflon tape on your spare tube valve. If you had to, you should be able to remove it and put it onto the new tube. (Also helps to ride with friends who have deep wheels)

Mavic used to sell valve extenders that included small o-rings but I haven't been able to find these in awhile.
There are other brands that make them. I have a few but can't remember the brand.
 

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Right, so they are removable core extenders, so you need removable core valves on your tubes to use ones like that.
You don't HAVE to use ENVE extenders, can use whatever you want.
Just get Conti Race 28 tubes with 80mm valves. So. Much. Easier.
 

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Discussion Starter #14
Right, so they are removable core extenders, so you need removable core valves on your tubes to use ones like that.
You don't HAVE to use ENVE extenders, can use whatever you want.
Just get Conti Race 28 tubes with 80mm valves. So. Much. Easier.
Wouldn't that not work with a 70mm rear wheel depth? Only 10mm for the pump to grab?
 

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It would be close, and I guess that's up to you to work out what you can live with.
It would actually be closer to 20mm as I assume the 70mm wheel depth is measured including the brake tracks, the valve only has to go through from the base of the tyre bed so you gain a bit there. As an example on my Zipp 404's (58mm deep wheel) I have 25mm of valve to the top of the threads showing and 30mm to the top of the knurled nut that you unscrew on an 80mm Conti tube. I use a Lezyne floor pump that screws onto the valve head so I don't have to seat a bigger clip on pump head to the valve either.
 

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Discussion Starter #16
It would be close, and I guess that's up to you to work out what you can live with.
It would actually be closer to 20mm as I assume the 70mm wheel depth is measured including the brake tracks, the valve only has to go through from the base of the tyre bed so you gain a bit there. As an example on my Zipp 404's (58mm deep wheel) I have 25mm of valve to the top of the threads showing and 30mm to the top of the knurled nut that you unscrew on an 80mm Conti tube. I use a Lezyne floor pump that screws onto the valve head so I don't have to seat a bigger clip on pump head to the valve either.
Good call, forgot about the brake track. I was wondering how a 48mm valve on my other tubes left me with ~28mm left over on my 35mm deep wheels.

The ENVE extenders are rubberized so they don't knock around in the wheel so I'll try those at first. If I don't like them I'll get 80mm tubes. Thanks for the help.
 

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Ok, I'm in the same boat here - have a stack of new 42mm presta Race 28 Continental tubes - Do they have removable cores? (I'm not at home to look at them for a couple days) ENVE 4.5s will be here Monday and they come with ENVE supplied extenders, so it sounds like I may need to get a different extender or different tubes to go with them.
 

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...'Dish' is how the rim is centered over the hub. 'Section' describes the rim shape...
I think we're losing the battle on that one. I guess wheels can have dish, and pizza can be be deep dish, so why not deep dish wheels? After all, we do have tacoed wheels, to continue with the fast food analogies.
 
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