Bicycle Mechanics - Presta Valve VS Schrader Valve

I just noticed today that my tire needs a little air, when i tried to inflate it i notice that it's not your regular valve, when to my local bike shop, they told me what i have is called "presta valve". What is the benefit of having this valve?? and can i go back to the regular valve (schrader valve)?

Presta: Primary the smaller hole in the rim, which makes the rim stronger... it's also a bit easier to pump up since the nut can prevent the valve from prairie doggin' in the rim.

Presta valves dont require as large hole in the rim as Schrader valves. Presta pumps can be made without a check valve which makes the lighter and more reliable (today most frame pumps are convertible so they don't take advantage of this). Converting to schrader requires that your rim be drilled to accept the larger valve, depending on your rim this may weaken it. You can always put an adapter on that will let you fill your tires with a Schrader pump.

Chances are that the hole in your rim is not big enough for a Schrader valve.
Presta valves seem normal to me.

http://www.sheldonbrown.com/brandt/presta-schrader.html

The presta valve is "regular" for high-pressure low-volume applications like narrow wheelchair and bicycle tires. The advantage is that the valve only opens when the pump is putting air into it. The pump pressure opens the valve, and when pressure is absent, the valve closes. You can achieve higher pressures with a hand pump that way. With a schrader valve, the valve opens when the pump head engages with it, so the pump is always at the same pressure as the tube. This makes it very hard to reach and maintain high pressures with a manual pump. Presta valves also happen to be smaller in diameter than schraders, making them more suitable to narrow rims; a smaller valve hole means less compromise of the rim's structural strength.

Usually what kind of bikes have Presta valves? Or is it random?

Presta valves main reason for success is due to the fact that they are easier to pump higher pressures of air into the valve because their is no valve spring to overcome as is with the Schrader.

The nut does help prevent the Presta valve from receding into the rim when attempting to pump a flat tire...BUT...I never used those nuts in over 35 years of using Presta valves! I simply hold my mini pump with 4 fingers at the base and loop my thumb over the rim and around the tire and hold press the tire into the rim (with the thumb) and pump, doing it this way also helps keep the valve straight while pumping so you don't accidentally tear off the valve or bend the valve core.

Along with that, as Electrik said it makes the rim stronger.

As a side note, you also do not need to use the plastic cap to put over the valve core nut like you do with the Schrader because when you tighten (just snug, not real tight) down the knurled little barrel nut serves as a cap, but I use the cap anyway so the little barrel nut doesn't accidentally get bent. I've had them get bent and not even know why, but a slight bend can make the valve useless, and bending it back sometime breaks it.


Schrader valves are sturdier though.

no its not random ..
Schrader on Low pressure tires , MTBs, for the Lumpen Prolo's and the bottom of the price-range.

no its not random ..
Schrader on Low pressure tires , MTBs, for the Lumpen Prolo's and the bottom of the price-range.

Actually Schrader valves are used daily in applications upwards to 15,000 PSI. So no, their not limited to low pressure. And 747 jumbo jets require 175 to 180psi on the nose tires and 200 to 205 on the main gear...and they use Schrader. And once, for a unrelated experiment, I put 210 psi in a MTB tire and Schrader held just fine...I was more worried about the rim and tire, the valve wasn't even a remote concern.

Presta valves are easier to fill and easier to take a smidge air out of when I need more traction in the winter.

Schrader = Pffft.

Actually Schrader valves are used daily in applications upwards to 15,000 PSI. So no, their not limited to low pressure. And 747 jumbo jets require 175 to 180psi on the nose tires and 200 to 205 on the main gear...and they use Schrader. And once, for a unrelated experiment, I put 210 psi in a MTB tire and Schrader held just fine...I was more worried about the rim and tire, the valve wasn't even a remote concern.

But airplane landing gear doesn't have in its design requirements the ability to be inflated with a frame pump.

But airplane landing gear doesn't have in its design requirements the ability to be inflated with a frame pump.
That's been irrelevant since the mid-70s when Zefal came out with their thumb-lock design for their frame pumps. Ever since then it has been equally easy to inflate the two valve types by hand. And the rim strength argument is also irrelevant except possibly for the very narrowest rims. I've drilled out quite a few rims to allow Schrader valves to fit and not one has ever failed at the valve hole. Rims fail at the braking track and at spoke holes - valve hole failures are really rare. The final argument raised has been about the nut on threaded Presta valves. But note that 1) many people avoid the use of this nut even when available, and 2) lots of Presta valve stems are smooth on the outside and don't include this nut.

At this point I think the continued popularity of Presta valves is more one of fashion than anything else. Light road bikes have traditionally used Presta valves and so they continue to do so. And they are marginally lighter than Schrader.

That's been irrelevant since the mid-70s when Zefal came out with their thumb-lock design for their frame pumps. Ever since then it has been equally easy to inflate the two valve types by hand. And the rim strength argument is also irrelevant except possibly for the very narrowest rims. I've drilled out quite a few rims to allow Schrader valves to fit and not one has ever failed at the valve hole. Rims fail at the braking track and at spoke holes - valve hole failures are really rare. The final argument raised has been about the nut on threaded Presta valves. But note that 1) many people avoid the use of this nut even when available, and 2) lots of Presta valve stems are smooth on the outside and don't include this nut.

At this point I think the continued popularity of Presta valves is more one of fashion than anything else. Light road bikes have traditionally used Presta valves and so they continue to do so. And they are marginally lighter than Schrader.


This is true to a point. Older generation of rims where not as good as the ones today and suffered from cracks and thus the Presta valve was developed. But presta valves are also lighter then schrader and roadies are mostly weight weenies and would cringe have to use a big bulky heavy schrader valve. So it's a little more then just fashion, but fashion is part of it. I never use the nut as I said earlier, and my current tubes didn't even come with one because the shaft is smooth.

At this point I think the continued popularity of Presta valves is more one of fashion than anything else. Light road bikes have traditionally used Presta valves and so they continue to do so. And they are marginally lighter than Schrader.

Not fashion but function. Presta valves are held shut by the pressure inside the tire/tube. To fill them, you only need to overcome that internal pressure by a small amount to open the valve. Any air that goes into the tube stays there. When you release the pump head, there is absolutely no leakage from the tube so the pressure inside the tube can be accurately read and maintained.

With a schrader valve, the valve has to be opened, and held open, to put air in it. If the pump head is improperly sealed on the valve stem, you can...and often do...lose air from from the tire/tube. If the point is to add air to the tire, why would you want to lose any to begin with? The seal around the stem is much more critical for schrader, too. Even with a good seal, there is going to be some pressure release when the pump head is removed.

There is also an issue...a slight one but it's still relevant...of damage. Schrader valves are much more prone to cuts from the valve hole than prestas are. Especially in low pressure situations. On a mountain bike, for example, the high torque and low pressure can lead to tube creep. If the rubber covered schrader valve creeps too far, it can cut the stem. Prestas can't suffer stem cuts in the same manner. The little nut on presta valves, by the way, helps prevent creep in those kinds of applications. Presta valves can be damaged from the pressure pushing the stem out of the rim but schraders can also suffer from this kind of damage.

Go to the LBS and ask for a Presta-Schrader adapter.
Probably cost a buck or two.
Then you can use any Schrader pump.

Not fashion but function. Presta valves are held shut by the pressure inside the tire/tube. To fill them, you only need to overcome that internal pressure by a small amount to open the valve. Any air that goes into the tube stays there. When you release the pump head, there is absolutely no leakage from the tube so the pressure inside the tube can be accurately read and maintained.

With a schrader valve, the valve has to be opened, and held open, to put air in it. If the pump head is improperly sealed on the valve stem, you can...and often do...lose air from from the tire/tube. If the point is to add air to the tire, why would you want to lose any to begin with?

True in principle, but as I stated above, this has been a non-issue ever since Zefal introduced their thumb-lock HP frame pump around 1976. It and similar pumps by others since then seal around the top of the valve just before depressing the little pin in the Schrader valve so the only air lost is a few ml that go into the very end of the pump - maybe you lose 0.1 psi before you start pumping. This used to be a big problem back when the Schader pin was depressed by a knob inside the tube you had to screw down onto the valve. You'd be frantically unscrewing the tube with the air hissing out and hoping you wouldn't lose too much pressure. With frame pumps designed in the last few decades this is a non-issue. Now there is far more air lost from the Presta valve since those frequently need to have the valve opened a bit manually before using a pump to avoid having the valve stick closed and refuse to let in any air from the pump.


There is also an issue...a slight one but it's still relevant...of damage. Schrader valves are much more prone to cuts from the valve hole than prestas are. Especially in low pressure situations. On a mountain bike, for example, the high torque and low pressure can lead to tube creep. If the rubber covered schrader valve creeps too far, it can cut the stem. Prestas can't suffer stem cuts in the same manner. The little nut on presta valves, by the way, helps prevent creep in those kinds of applications. Presta valves can be damaged from the pressure pushing the stem out of the rim but schraders can also suffer from this kind of damage.
Again, possible in principle, but I have yet to see a cyclist have this problem with a Schrader valve while I have seen quite a few Presta valve failures when they either bent the valve while pumping or had it pull out of the tube when removing their pump. The creep issue doesn't arise at the tire pressures that I use on my bikes. The Schrader valves appear to be considerably more durable and less subject to damage from abuse while pumping.

There is also an issue...a slight one but it's still relevant...of damage. Schrader valves are much more prone to cuts from the valve hole than prestas are. Especially in low pressure situations. On a mountain bike, for example, the high torque and low pressure can lead to tube creep. If the rubber covered schrader valve creeps too far, it can cut the stem. Prestas can't suffer stem cuts in the same manner. The little nut on presta valves, by the way, helps prevent creep in those kinds of applications. Presta valves can be damaged from the pressure pushing the stem out of the rim but schraders can also suffer from this kind of damage.

Really? I've never heard of this about schrader's unless the tire is flat. If this were true then all the MTB racers would be using presta. And I've had presta valved tubes pushing 130psi without using the nut and never had a stem "push" it's way out of a rim, and what about tubulars pushing 200psi using prestas? Nor I have I heard of schrader doing the same thing. All damage I've seen from Presta valves was due to operator air; I will admit that shraders are less likely to get damaged due to operator error but it could happen.

I love these threads.

I love reading the people who make monumental mountains out of miscule molehills. Usually somebody says something about presta valves holding air pressure better but that's already been de-bunked.

To me, Presta wins the "smaller hole in the rim is stronger" points. On the other hand, I've never seen a rim fail at the valve hole.

Schrader wins, by a mile, the valve stem tearing battle. If you're getting enough tire creep to cut a Schrader valve, a presta valve stem is going to tear loose from the inner tube. And frankly, I think that little nut causes lots more tube damage than it prevents.

Difficulty to inflate in the real world is a Presta win by a nose if you are using a hand pump and a Schrader win by a mile if you have an air compressor.

Now there is far more air lost from the Presta valve since those frequently need to have the valve opened a bit manually before using a pump to avoid having the valve stick closed and refuse to let in any air from the pump.

Again, possible in principle, but I have yet to see a cyclist have this problem with a Schrader valve while I have seen quite a few Presta valve failures when they either bent the valve while pumping or had it pull out of the tube when removing their pump. The creep issue doesn't arise at the tire pressures that I use on my bikes. The Schrader valves appear to be considerably more durable and less subject to damage from abuse while pumping.


Wrong, wrong, wrong. You don't understand the presta design. It's normal to tap the top to free-up the seal before trying to add air to a tire. If you don't it may take 150 psi just to break the seal. That is normal. There is ZERO air lost with a presta because the valve seals as soon as the pump pressure is the same as the what's in the tire. When you remove a presta head, all of the escaping air is in the pump.

To the OP, if there is a small black plastic rim around the base of the valve, then you can take that out and use a Schraeder ( car type ) valve. If not, you can drill out ( carefully ) the rim to accept the Schraeder, or get an adapter that will let you top up at a compressor.

Anyway, you should have a floor pump at home, they're not expensive, and they almost always do both types of valve.

Wrong, wrong, wrong. You don't understand the presta design. It's normal to tap the top to free-up the seal before trying to add air to a tire. If you don't it may take 150 psi just to break the seal. That is normal. There is ZERO air lost with a presta because the valve seals as soon as the pump pressure is the same as the what's in the tire. When you remove a presta head, all of the escaping air is in the pump.
Oh, I think I understand the Presta design just fine and have been using the things for the last 40 years.

But 'cycocommute' indicated that a problem with Schrader valves was "If the point is to add air to the tire, why would you want to lose any to begin with?" i.e. the tiny amount of air lost when first putting the pump head on the valve. Since that air loss is minimal compared to the amount lost when tapping the Presta valve to avoid the sticky seal issue this is a net win for the Schrader design - not that it's a big deal for either valve type. Yes, it is normal - but it still results in a loss of some air.

And sure, the Presta valve doesn't lose air when the pump is disconnected, but the point was that this is also essentially true for Schrader valves as long as you're using a decent pump designed sometime after the mid-70s. The head is designed so the pin in the valve is released thus sealing the tube simultaneous with or just before the seal to the pump head is broken, so there's no significant air loss at disconnection with either valve design.

I use both valves (not only have I used both valves about equally on several different bikes, over the last several years, the bike I currently ride has schrader on the back wheel and presta on the front) and I favor schrader. Schrader seems to be more "robust", I've torn a few presta valves near the stem which taught me to be more gentle with them (and to pull straight up more-so than side-to-side when disconnecting the pump-head). My schrader valve instantly blows the pump head (of my floor pump) off when I flip the engage/disengage lever when disconnecting. Disconnecting from presta takes a little tugging (my presta valves are not smooth on the sides so that may contribute to this slight stubborness to disconnect). The pumps I use have dual heads (one hole for schrader, another hole for presta) and I don't notice an obvious difference when pumping my tires to 100 + psi (at least that is what the gauge on my pump reads), I'm not saying there is no difference, just that I don't notice an obvious one.

Though I favor schrader, I don't plan on having my presta rims altered for schrader, it's not THAT big of a deal to use presta, I just handle presta valves more delicately. I carry a presta-to-schrader adapter in my flat-repair kit to keep my options open (like using gas-station air) but have never used it (since my floor-pump and mini/portable pump both have dual-heads). I have fine-tuned my mini-pump technique with presta so that I don't tear the valve-stems out (I never got around to getting one of the mini-pumps with the hose included, like a Topeak road morph, which would be cool to have).

I also use both. Presta on my bikes, Schrader on my car.

Oh, I think I understand the Presta design just fine and have been using the things for the last 40 years.

Since that air loss is minimal compared to the amount lost when tapping the Presta valve to avoid the sticky seal issue this is a net win for the Schrader design - not that it's a big deal for either valve type. Yes, it is normal - but it still results in a loss of some air.


.

Well that comment right there told me all I needed to know about your experience in the last 40 years with Presta valves. All you need to do is just a quick very short air burp that at the most will lose 1/2 to 1 pound of air psi at the most.

If you really want to learn something then read this from Jobst Brandt, google him if you want to know who he is, read this site in it's entirety unless you just want to set there and pretend you know something you know nothing about.

http://yarchive.net/bike/presta.html

Well that comment right there told me all I needed to know about your experience in the last 40 years with Presta valves. All you need to do is just a quick very short air burp that at the most will lose 1/2 to 1 pound of air psi at the most.
As I said - it's not a big deal with either valve type. But that short air burp from the Presta valve is still a loss of much more air than I get when putting the head of any decent thumb-lock pump on a Schrader valve.

I agree with Jobst's comments, but the two advantages he cites for Presta have lost their practical significance for all but the very narrowest of rims.
The first is the supposed weakening of the rim due to the larger hole. True in principle, but I've never seen a rim fail at the valve hole - and that includes narrow rims made for 23 mm tires that have been reamed out enough to fit Schrader valves. Even with the larger hole, that area is still strong enough to last for the life of the rim before it fails from other problems - typically due to thinning of the brake surface or cracks at the spoke holes.

The second is that you can use a simpler pump since you don't need to include a check valve. Again, a true statement, but not relevant in practice since almost all frame pumps are now made to accommodate both types of valve so you get the check valve in the pump whether or not you need it. The old Silca pumps were very simple mechanically and only work with Presta valves, but I don't see many of them around anymore because pumps by Zefal, Topeak, and Lezyne work better (and these all include the check valve and are equally easy to use with either valve type).

As I said - it's not a big deal with either valve type. But that short air burp from the Presta valve is still a loss of much more air than I get when putting the head of any decent thumb-lock pump on a Schrader valve.

The air burp is irrelevant, IMO. It might take one more pump stroke to fill the tire. The advantages of the presta outweigh the disadvantages.

The only wheels that are made with Schrader-holed rims are on cheap bikes.

The air burp is irrelevant, IMO. It might take one more pump stroke to fill the tire. The advantages of the presta outweigh the disadvantages.

The only wheels that are made with Schrader-holed rims are on cheap bikes.

1. I agree with you that the air "burp" is irrelevant. To me it's on the same scale as depressing the Schrader spring.

2. You said "advantages" plural. Other than the smaller rim hole, what might they be?

3. One week ago today my wife bought a $2,500 Greenspeed trike. It uses Schrader tubes. So what's your threshold value for not-cheap? (Incidentally, that thing is an utter gas to ride.)

True in principle, but as I stated above, this has been a non-issue ever since Zefal introduced their thumb-lock HP frame pump around 1976. It and similar pumps by others since then seal around the top of the valve just before depressing the little pin in the Schrader valve so the only air lost is a few ml that go into the very end of the pump - maybe you lose 0.1 psi before you start pumping. This used to be a big problem back when the Schader pin was depressed by a knob inside the tube you had to screw down onto the valve. You'd be frantically unscrewing the tube with the air hissing out and hoping you wouldn't lose too much pressure. With frame pumps designed in the last few decades this is a non-issue. Now there is far more air lost from the Presta valve since those frequently need to have the valve opened a bit manually before using a pump to avoid having the valve stick closed and refuse to let in any air from the pump.

I've been using thumb-lock pumps since I start bicycling. I've never used threaded on pumps (other than shock pumps but that's a different issue)...didn't see the sense in them. Schrader does have the problem of proper sealing that presta does not. Since you have to open the valve on a schrader to fill it, there is always a chance of leakage if the seal around the valve is poor. My experiences with schrader valves using hand pumps is that the seal is often poor.

Prestas only require over-pressure to open them. The only reason to burp them is to avoid having to pump to very high pressures as DaveSSS alludes to above.


Again, possible in principle, but I have yet to see a cyclist have this problem with a Schrader valve while I have seen quite a few Presta valve failures when they either bent the valve while pumping or had it pull out of the tube when removing their pump. The creep issue doesn't arise at the tire pressures that I use on my bikes. The Schrader valves appear to be considerably more durable and less subject to damage from abuse while pumping.

The presta stem can be damaged by ham-handed use. But I've seen...and experienced...far more cut valve stems on schrader valves than bent stems on presta valves. If you ride a presta stem on a tire that is going flat slowly or in low pressure applications (with the stem nut in place), the tube will not creep. If you ride a scrader valve on a tire that is going flat slowly or in low pressure applications, you always risk stem creep and a cut stem.

There are lots of people out there who use bikes where pressures are intentionally kept low. For uphill off-road riding, a pressure of less than 45 psi is almost required. Often pressure of 10 to 15 psi less than that are used. Just because you might not use low pressure doesn't mean that other's might not.


Really? I've never heard of this about schrader's unless the tire is flat. If this were true then all the MTB racers would be using presta. And I've had presta valved tubes pushing 130psi without using the nut and never had a stem "push" it's way out of a rim, and what about tubulars pushing 200psi using prestas? Nor I have I heard of schrader doing the same thing. All damage I've seen from Presta valves was due to operator air; I will admit that shraders are less likely to get damaged due to operator error but it could happen.

I'll bet most MTB racers do use presta.

The stem/rubber interface can be damaged in prestas...or schraders...if the rim tape is poor and the edges of the valve stem hole are sharp. Of course the stem is pressed up into the rim. It's a pressure system and that's the only place where the pressure can escape. Think of what happens if the rim tape allows the tube to sneak past a spoke hole. The valve stem hole just happens to have a valve plugging it.

The nut on a presta doesn't keep the stem from being pressed out. It does keep the tube from creeping if you happen to ride on a flat(ish) tire.

...
I'll bet most MTB racers do use presta.

The stem/rubber interface can be damaged in prestas...or schraders...if the rim tape is poor and the edges of the valve stem hole are sharp. Of course the stem is pressed up into the rim. It's a pressure system and that's the only place where the pressure can escape. Think of what happens if the rim tape allows the tube to sneak past a spoke hole. The valve stem hole just happens to have a valve plugging it.
...


They do, but for the majority of flats i've have due to valve-stem to tube interface have been presta and at the very bottom of the valve(often look like cracked rubber)... i'm not sure if there is more torque or what - but these tires were at lower psi than normal though at the same psi as the schraders.

Since you have to open the valve on a schrader to fill it, there is always a chance of leakage if the seal around the valve is poor. My experiences with schrader valves using hand pumps is that the seal is often poor.


A leaky seal or a faulty hose on a Schrader valve could lead to losing whatever pressure you already have in the tube due to the fact that the valve has already been opened. On a presta valve since the valve itself is a check valve this is not an issue.

As I said - it's not a big deal with either valve type. But that short air burp from the Presta valve is still a loss of much more air than I get when putting the head of any decent thumb-lock pump on a Schrader valve.

I agree with Jobst's comments, but the two advantages he cites for Presta have lost their practical significance for all but the very narrowest of rims.
The first is the supposed weakening of the rim due to the larger hole. True in principle, but I've never seen a rim fail at the valve hole - and that includes narrow rims made for 23 mm tires that have been reamed out enough to fit Schrader valves. Even with the larger hole, that area is still strong enough to last for the life of the rim before it fails from other problems - typically due to thinning of the brake surface or cracks at the spoke holes.

The second is that you can use a simpler pump since you don't need to include a check valve. Again, a true statement, but not relevant in practice since almost all frame pumps are now made to accommodate both types of valve so you get the check valve in the pump whether or not you need it. The old Silca pumps were very simple mechanically and only work with Presta valves, but I don't see many of them around anymore because pumps by Zefal, Topeak, and Lezyne work better (and these all include the check valve and are equally easy to use with either valve type).

Again your incorrect. When you hook up a pump to a schrader valve there is an air loss that goes on. Your pump has to overcome a spring in the schrader and when that happens there is air loss. You could argue that there's more in the presta, but you would be wrong if you look at the precentages. With a Presta your dealing with at least 95psi in a road clincher vs 65 in a mtb clincher, thus the greater pressure would stand for reason that their would be a bit more air loss, but over all if all psi was the same you would lose more air with the Schrader then a presta solely due to having to overcome the spring despite burping the Presta.

And I have older Silca Imperio with the Campy head and an older Zefal HPX, and neither leak any less or more then the modern pumps I have irregardless of check valves. And both, the old and the new, are just as easy to use.

A leaky seal or a faulty hose on a Schrader valve could lead to losing whatever pressure you already have in the tube due to the fact that the valve has already been opened. On a presta valve since the valve itself is a check valve this is not an issue.

I believe I already said this.

With a Presta your [sic] dealing with at least 95psi in a road clincher vs 65 in a mtb clincher, thus the greater pressure would stand for reason that their [sic] would be a bit more air loss, but over all if all [sic] psi was the same you would lose more air with the Schrader then [sic] a presta solely due to having to overcome the spring despite burping the Presta.

And I have older Silca Imperio with the Campy head and an older Zefal HPX, and neither leak any less or more then [sic] the modern pumps I have irregardless [sic] of check valves. And both, the old and the new, are just as easy to use.
Actually on the bikes I currently use, the Schrader valve gets used with 125 psi on our tandem and the Presta gets used at 80 psi on my touring bike. I also use a Zefal HP (and HPX) pump on the Schrader valve on the tandem and there is no noticeable loss of air when putting the pump head on the valve since the seal is in place when the pin in the pump gets depressed. My pump forms a good seal even before I throw the thumblock - the lock just acts to keep the pump head solidly attached. In contrast, I always hear a momentary hiss of escaping air when freeing up the Presta valves on my touring and road bikes. And yes, I agree that this little bit of air loss is normal and not a problem, but the lack of this little air loss is also normal and not a problem for the Schrader valves when used with those same pumps.

So with these pumps both valve types are easy and convenient to pump. The Silca also works reasonably well, although only with Presta - but it's not nearly as easy to get up to the 125 psi pressure I want to use on the tandem. So these days I've quit using that style pump and stick with ones (like the Zefal and Topeak) that are easier to use to get to high pressures. And those pumps work just as easily with Schrader valves and with the little bonus that they don't require the 'burp' ritual that is needed with Presta. As for cyccommute's pumps with leaky seals all I can suggest is to get the seals fixed. Haven't encountered that problem myself, but if the seal is leaking air out then you aren't getting the best efficiency with either valve type even if it might be less critical with Presta.

And those pumps work just as easily with Schrader valves and with the little bonus that they don't require the 'burp' ritual that is needed with Presta. As for cyccommute's pumps with leaky seals all I can suggest is to get the seals fixed. Haven't encountered that problem myself, but if the seal is leaking air out then you aren't getting the best efficiency with either valve type even if it might be less critical with Presta.

But you do have to do a 'burp' ritual with the schrader...it's just slightly different. You have to depress the valve which will fill the pump from the head to whatever check valve the pump has in it. If that's a floor pump, you could be talking about a significant amount of air to fill the hose of the pump. A presta valve, since it is a natural check valve, doesn't require the same amount of air release into the pump mechanism. The presta will work without the 'burp' but you might need a significant amount of overpressure to open the valve. I've had presta valves that are sticky and won't release until you have pressurized them to several atmospheres (1 atmosphere = 14 psi). If you wiggle the pump chuck on the valve, you can often get it to release but you haven't lost any air inside the tire. The same can't be said of schrader. If you hear air leaking from a schrader tube, you are losing air from the tire because the valve is held open.

As for leaking seals, it's not the seals themselves that are the problem but how far onto the schrader stem they are placed. They are more difficult to seal around the stem and, if the seal is bad, they tend to leak more around the seal. And, as I said before, if air is leaking from a chuck on a schrader stem, air is leaking from the tire. I can pump up a schrader tube but I tend to avoid schrader valves if I can. Presta are just a more efficient and more elegant mechanism. I'd use them on my car if I could.

Actually on the bikes I currently use, the Schrader valve gets used with 125 psi on our tandem and the Presta gets used at 80 psi on my touring bike. I also use a Zefal HP (and HPX) pump on the Schrader valve on the tandem and there is no noticeable loss of air when putting the pump head on the valve since the seal is in place when the pin in the pump gets depressed. My pump forms a good seal even before I throw the thumblock - the lock just acts to keep the pump head solidly attached. In contrast, I always hear a momentary hiss of escaping air when freeing up the Presta valves on my touring and road bikes. And yes, I agree that this little bit of air loss is normal and not a problem, but the lack of this little air loss is also normal and not a problem for the Schrader valves when used with those same pumps.

So with these pumps both valve types are easy and convenient to pump. The Silca also works reasonably well, although only with Presta - but it's not nearly as easy to get up to the 125 psi pressure I want to use on the tandem. So these days I've quit using that style pump and stick with ones (like the Zefal and Topeak) that are easier to use to get to high pressures. And those pumps work just as easily with Schrader valves and with the little bonus that they don't require the 'burp' ritual that is needed with Presta. As for cyccommute's pumps with leaky seals all I can suggest is to get the seals fixed. Haven't encountered that problem myself, but if the seal is leaking air out then you aren't getting the best efficiency with either valve type even if it might be less critical with Presta.


I used the Silca Imperio (a frame pump) when I use to use tubulars and never had a problem getting the tires to 140psi, so I'm not sure which Silca you had that couldn't do that.

But I believe all the valves lose some air when either burping the presta or attaching the pump to a schrader. However when you release the pump the air loss your hearing in a presta is not coming from the tube but rather the air that's pressurized in the pump.

And cyccommute is correct, but I rather burp the presta valve by just giving a fast tap and it will burp for about a 10th of a second, not no where near enough air escaping to even amount to a 1/2 a pound. But really who cares how much air is released by either valve?? Your hooking up a pump to do one thing...PUT AIR INTO THE TIRE!! So your already hooking up the pump to put air in so what if you have to pump one time more to make up for the air that was lost? This all seems like a mute point to me. It's the same reason I went with latex tubes because every day I had to top of the tires when I used butyl tubes anyways, so why not go ahead and add another 15psi...I'm already pumping everyday anyways!! And latex feels more supple on the road then butyl.

But you do have to do a 'burp' ritual with the schrader...it's just slightly different. You have to depress the valve which will fill the pump from the head to whatever check valve the pump has in it. If that's a floor pump, you could be talking about a significant amount of air to fill the hose of the pump. A presta valve, since it is a natural check valve, doesn't require the same amount of air release into the pump mechanism. The presta will work without the 'burp' but you might need a significant amount of overpressure to open the valve. I've had presta valves that are sticky and won't release until you have pressurized them to several atmospheres (1 atmosphere = 14 psi). If you wiggle the pump chuck on the valve, you can often get it to release but you haven't lost any air inside the tire.


Nope, no 'burp' needed with the Schrader valve. The pin is depressed by a little knob inside the pump head that pushes on it *after* there's already a seal between the pump and the valve. The amount of space that fills with air when the pin is depressed is probably a couple ml - totally insignificant and certainly a tiny fraction of the air lost when the Presta valve is 'burped' - which is itself still an insignificant amount of air loss. I quit trying to inflate Presta valves without doing the ritual 'burp' after I had several where I got up to the 220 psi limit of my floor pump gauge and they still hadn't released (and the wiggle trick doesn't always work).

And yes - "If you hear air leaking from a schrader tube, you are losing air from the tire" - but the point is that I *don't* hear any air leaking from the Schrader valve connected to my pumps - I suggest you fix yours and you won't have that problem.


As for leaking seals, it's not the seals themselves that are the problem but how far onto the schrader stem they are placed. They are more difficult to seal around the stem and, if the seal is bad, they tend to leak more around the seal. And, as I said before, if air is leaking from a chuck on a schrader stem, air is leaking from the tire. I can pump up a schrader tube but I tend to avoid schrader valves if I can. Presta are just a more efficient and more elegant mechanism.
I'm puzzled as to why you seem to encounter such difficulties with the seals on your pumps. My experience is that I have no trouble inflating either type of valve with my frame pumps or floor pumps - so there is no efficiency advantage and the 'elegance' is in the eye of the beholder. It doesn't appear in mine.

I rather burp the presta valve by just giving a fast tap and it will burp for about a 10th of a second, not [sic] no where near enough air escaping to even amount to a 1/2 a pound. But really who cares how much air is released by either valve?? Your [sic] hooking up a pump to do one thing...PUT AIR INTO THE TIRE!! So your [sic] already hooking up the pump to put air in so what if you have to pump one time more to make up for the air that was lost? This all seems like a mute [sic] point to me. It's the same reason I went with latex tubes because every day I had to top of the tires when I used butyl tubes anyways, so why not go ahead and add another 15psi...I'm already pumping everyday anyways!! And latex feels more supple on the road then [sic] butyl.

I agree completely (although I think if you measure it the pressure loss will be much more than 0.5 psi). Cycommute was the one who raised the issue of losing some air before starting to pump as a supposed advantage of Presta valves and I was merely responding to that claim. I have always said that the amount of air lost is insignificant. But it's even less significant when I pump up my Schrader valves where I never notice any air loss.

Nor did I ever claim that I couldn't pump my tires to full pressure with the Silca pump - only that I found it easier to do so with the Zefal and Topeak ones. The Silca pump is larger in diameter than the Zefal and therefore requires more force for a given pressure and it doesn't have the 'mini-floor pump' style of the Topeak that makes it easier to exert the necessary force.

Nope, no 'burp' needed with the Schrader valve. The pin is depressed by a little knob inside the pump head that pushes on it *after* there's already a seal between the pump and the valve. The amount of space that fills with air when the pin is depressed is probably a couple ml - totally insignificant and certainly a tiny fraction of the air lost when the Presta valve is 'burped' - which is itself still an insignificant amount of air loss. I quit trying to inflate Presta valves without doing the ritual 'burp' after I had several where I got up to the 220 psi limit of my floor pump gauge and they still hadn't released (and the wiggle trick doesn't always work).

And yes - "If you hear air leaking from a schrader tube, you are losing air from the tire" - but the point is that I *don't* hear any air leaking from the Schrader valve connected to my pumps - I suggest you fix yours and you won't have that problem.

Depressing the pin on the valve is the burp. Air loss to the pump with a schrader is far greater than the air loss to burping a presta valve. If you are using a floor pump, the air loss is much, much greater.

The issue of air leaking from the pump head is that it happens with either valve for various reasons. You are in a hurry. The valve stem isn't clean. The threads on the valve may be buggered. The chuck is old and/or cracked. There's a ton of reasons why you might have leakage around the stem seal. The point being that if you hear leaking around the stem seal of a presta valve, there's no reason to worry about the seal. Any air that goes into the tube will stay there. With a schrader, you have to either pump faster or reposition the chuck to get a better seal. If you reposition the chuck, you lose any more air.


I'm puzzled as to why you seem to encounter such difficulties with the seals on your pumps. My experience is that I have no trouble inflating either type of valve with my frame pumps or floor pumps - so there is no efficiency advantage and the 'elegance' is in the eye of the beholder. It doesn't appear in mine.

I don't encounter a lot of problems with the seals on pumps but it does happen. No concern with a presta if it does. You'd better fix the problem if you use schrader.

I use whatever the rims I have are drilled for. Meh, I couldn't care less if I were using presta or schrader valves. I just wish they were all the same so I didn't have to keep so many different tubes "in stock" ;)

I use whatever the rims I have are drilled for. Meh, I couldn't care less if I were using presta or schrader valves. I just wish they were all the same so I didn't have to keep so many different tubes "in stock" ;)

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For those new to Presta Valves, here's a good YouTube vid explaining how they work. http://www.youtube.com/watch?v=9byRp9e2USU