13
votes
Accepted
What air attachment screws onto a Presta valve with the core removed? High volume for seating bead?
Inflator heads with Presta fittings let you do this because they tend to (always?) seal down around the stem, not the core. I don't know any other way. I suppose you could also take a spare Presta ...
- 81.7k
10
votes
Are presta valve cores universal?
I always save the core out of blown tubes and have never had them not compatible. At the bike store you just see one jar. Might someone come out with non-standard - it could happen.
- 15.6k
8
votes
Accepted
Considering modern bicycle trends (2021), why are presta valves still the dominant design?
I think you are correct; there is no technical advantage of Presta. But many things are not used for technical reasons but rather for momentum reasons.
Personally I prefer schrader for all my bikes, ...
- 3,316
8
votes
Considering modern bicycle trends (2021), why are presta valves still the dominant design?
Presta (btw: we call it Sclaverand or simply road bike valve here in Austria) has one advantage: You can easily release air.
There could also be some small weight savings and aerodynamic benefits. I ...
- 26k
8
votes
Roadside repair: how to use a screw-on Presta pump on a tube with a removable valve core
I once saw someone riding out of a bike park with their minipump wedged in the front wheel and tied to the hub between the spoke planes with a clean poop-bag.
They'd had exactly this problem where the ...
- 121k
8
votes
Accepted
How does a Presta valve core work?
Working from left to right of your first example:
The black rubber gasket, when the brass nut is sufficiently tight, prevents air from passing through the core.
The white rubber gasket, when the ...
- 3,449
7
votes
stop air leak when disconnecting inflator from presta valve
In my experience there is always some air loss when you remove the pump from a Presta valve, but that air is lost from the pump side of the valve.
It's easier to see with a floor pump, since there's ...
- 23.3k
7
votes
Accepted
Can a bike have both Schrader and Presta tires?
Short answer, it's not common at all and probably wasn't like that when the bike was new.
The valve that you need is determined by the rim rather than the bike. If the rim is drilled out with a big ...
- 4,175
7
votes
Accepted
What is this valve and how do I fill it?
This is a Dunlop valve, also known as Woods. These valves always let air in but not out. The nut holds the valve in place, and you are supposed to unscrew it only if you want to deflate the tube.
...
- 21.8k
7
votes
broken presta valve confusion
The valve is broken. You need a new inner tube. A new tube will cost $5 to $10, and most bike shops will charge $5 or so to change it for you. It's something you need to be able to do anyway. They'...
- 131
6
votes
Putting a Presta stem nut inside the rim?
It is a commonly used quick and dirty fix when you don't have a purpose-built grommet to install in a rim cut for a Schrader valve. It may also not be a terrible idea if, for whatever reason, your ...
- 457
6
votes
Accepted
How can I tell if my presta valves have removable cores?
Have a close look.
On a presta valve there is a wide threaded part that the lock ring attaches to. And a narrower part with the valve lock nut above it that the cap threads onto.
If the narrow part ...
- 5,766
6
votes
Accepted
Presta Valve Core bent
It happens, especially if you remove the pump head not perfectly vertically or you move the pump head while pumping.
You can avoid this by using a bit of hose on the mini pump like on this mini pump
...
- 46.1k
6
votes
Accepted
How to repair a twisted Presta valve?
As noted in this old question there exist Presta tubes from which the valve core can be removed; in this case it might be possible to replace the valve core.
However, yours appears to be a single ...
- 5,044
5
votes
Accepted
Massive loss of pressure in my front tire but it still holds air
A tube is a sealed system. If the rubber isn't punctured and the valve is closed, there isn't anywhere that air could have gone all at once like that. The only thing I can think of is maybe you do ...
- 2,795
5
votes
Presta Valve Core bent
I wouldn't worry about it. Repeatedly bending the core could cause it to break, but as a one-off, it should be fine. I quite often end up with slightly bent cores, and don't normally bother bending ...
- 1,185
5
votes
Schrader inner tube gets cut by Presta sized hole in rim
The cheapest solution is to try and remove the burrs or sharp edges that are cutting the tube. This can be done with a small file or a piece of emery cloth cut into a small strip and pushed through ...
- 18.4k
5
votes
Accepted
How to keep Presta valve core from detaching after inflation?
I've had this happen with some tubes - Continental, maybe? Conti tubes are compatible with valve extenders, so the valve on them does come off like this. You're probably screwing the chuck on too ...
- 10.6k
5
votes
How to prevent a Presta valve core from unscrewing when disconnecting a pump
Threadlocker.
Or bring a valve core wrench with you. For example this high quality metal one from Schwalbe (don’t get their cheap plastic one):
Some multi tools also have a notch somewhere for presta ...
- 26k
5
votes
Roadside repair: how to use a screw-on Presta pump on a tube with a removable valve core
I know you weren't carrying one, but there are multi-tools that include valve-core wrenches. There are also standalone valve-core wrenches, although that would be a bit fussy to carry on a ride.
...
- 29.2k
4
votes
Presta valve inner tube issue: area around the valve does not fill up
When you fill up an inner tube outside of a tire, the area near the valve will look a bit constricted because the rubber is reinforced in that area:
However, when you fill it inside the tire, don't ...
- 29.1k
4
votes
Is there a work around to a presta valve not engaging a tire inflater pin?
You're using the wrong inflator valve on your compressor.
You're likely using this type of inflator valve (aka chuck). It requires the inner pin of the schrader valve of the tire to depress the ...
- 29.1k
4
votes
Locking pump dual nozzle on presta valve doesn't work
This really depends on the specific model and design of your dual head (i.e. two valve holes, one for presta and one for schrader).
I've seen at least three variations of dual pump head mechanisms:
...
- 29.1k
4
votes
Presta valve on new tube won't inflate
Perhaps its obvious, but maybe the tube has a leak? Is it an old tube that has perished and is just letting air out as fast as you pump it in?
Perhaps try taking the tube off the wheel, put it in a ...
- 1,335
4
votes
Putting a Presta stem nut inside the rim?
No, there is no reason for that type of installation unless the whole in the rim is sized for a Schrader valve, rather than a presta valve.
It is, as you found, unlikely to cause an issue though.
- 29.9k
4
votes
Schrader tubes in Presta configured Rims?
Actually, correct drill bit size is 21/64", not 3/8"
http://sheldonbrown.com/gloss_sa-o.html - search for Schrader
- 161
4
votes
Can a bike have both Schrader and Presta tires?
Why not? The bike will roll anyway. You would need two pump heads or an adapter to pump both tires, but other than that, it will work just fine.
- 14.4k
4
votes
Presta to Schrader valve adapters that don't screw on the valve core
Never seen one myself - there are pumps that have push-on "speed" adapters for presta, but they are part of the pump head and you wouldn't find one at the service station.
The best fix is to ...
- 121k
4
votes
Presta to Schrader valve adapters that don't screw on the valve core
SKS makes a press-on adapter. Unscrew the valve nut, push the adapter on, use the schraeder head on the air hose, pull the adapter off and thread the valve nut back down. Tell your shop it's p/n ...
- 131
4
votes
How to prevent a Presta valve core from unscrewing when disconnecting a pump
Like folks have said, locktite is great (use non permanent!) and it's a good idea to keep extra valve cores and core tool with you, although a couple small allen keys + pliers will do the trick, ask ...
- 41
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