# Why do road bicycle tire valves have to be such a pain in the ass? **URL:** \ **Category:** Factual Questions\ **Created:** [August 17, 2014, 3:38am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738 "2014-08-17T03:38:22Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Dog80](https://avatars.discourse-cdn.com/v4/letter/d/6bbea6/32.png) [@Dog80](https://boards.straightdope.com/u/Dog80)\ **Post date:** [August 19, 2014, 12:12pm UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/41 "2014-08-19T12:12:24Z")
> [@Machine\_Elf](#): > > Let’s compare your bike tire to a car tire. There are a few key differences that explain why your bike tire can lose several PSI per day while your car tire may lose just a couple of psi per year. > > First, the inner tubes are porous. Butyl rubber has relatively low permeability (compared to other polymers that could be used in this application) for O2 and N2, but it’s not zero. Cars have a nice thick layer of it on the inside of their tires to limit the egress of air. OTOH, the inner tubes on your bicycle are paper-thin to keep weight to a minimum. For a given psi, the mass flux (mass per unit time per unit of tube surface area) through your bicycle tires will be substantially higher on this basis alone. > > The shape is different, too. Take a car tire and a bike tire, and for each one, divide its surface area by its enclosed air volume. The bicycle tire will have a _far_ higher ratio, which tells you that for a given amount of air mass escaping, the bicycle tire will experience a greater psi drop. > > And then there’s the fact that car tires are tubeless - meaning about half of the surface area exposed to compressed air is the impermeable steel or aluminum of the rim. So take your car tire’s surface-area-to-volume ratio, calculated in the previous paragraph, and cut it in half again. > > Finally, the pressure. The permeation of air through the tire is driven by air pressure - specifically, the difference in pressure between the inside of the tire and the outside. You car tire has about 35 psi in it, but your bike tire, depending on model, could have well over 100 psi. That alone guarantees about 3X the mass flux for the bicycle tire versus the car tire. > > So if you want your bicycle tires to lose less psi per day, be prepared for some changes: > > -a thicker, heavier inner tube > -a larger tire volume > -a lower pressure in the first place > > In short, what you want is a [balloon tire.](http://en.wikipedia.org/wiki/Bicycle_tire#Balloon) This. Also a road bike tire actually carries a very small amount of air. That means that it doesn’t take much air loss to have a dramatic drop in pressure. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [August 19, 2014, 3:06pm UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/42 "2014-08-19T15:06:04Z")
> [@Mister\_Rik](#): > > One of my primary reasons for switching from mountain bikes to a road bike was to get away from those fat tires. You might still try 28mm tires, or even 32mm, if they fit your bike. They improve ride quality, allow you to use lower air pressure, and lose air at a slower rate. The difference in speed is usually negligible. ---
**Author:** ![cmdrpiffle](https://avatars.discourse-cdn.com/v4/letter/c/b4bc9f/32.png) [@cmdrpiffle](https://boards.straightdope.com/u/cmdrpiffle)\ **Post date:** [August 19, 2014, 5:59pm UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/43 "2014-08-19T17:59:12Z")
Just wow, an entire thread all to explain to Mister Rik how to put air in a tire. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [August 19, 2014, 9:14pm UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/44 "2014-08-19T21:14:30Z")
> [@cmdrpiffle](#): > > Just wow, an entire thread all to explain to Mister Rik how to put air in a tire. **Moderator Warning** **samclem** has already cautioned you not to be insulting to other posters in this forum. This is an official warning. Do not do this again. Colibri General Questions Moderator ---
**Author:** ![Mr.Nylock](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Mr.Nylock](https://boards.straightdope.com/u/Mr.Nylock)\ **Post date:** [August 20, 2014, 4:29am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/45 "2014-08-20T04:29:26Z")
The purpose of the presta valve is that it does not lose as much PSI when pulling the chuck off compared to a schrader - having as close to the exact right PSI is important to performance oriented riders, but no big deal to anyone else. They are a pain in the ass though, it has to be the most frequent problem that people have asked me about in the years I’ve worked in bicycle shops, I don’t think I’ve encountered anyone who is new to cycling who found them simple and easy to use. Some people use nitrogen to fill their tires so that their is less rapid loss of PSI. I don’t know anyone personally that does that though. ---
**Author:** ![Clawdio](https://avatars.discourse-cdn.com/v4/letter/c/d07c76/32.png) [@Clawdio](https://boards.straightdope.com/u/Clawdio)\ **Post date:** [August 20, 2014, 4:04pm UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/46 "2014-08-20T16:04:30Z")
I’m still confused about having to hold the pump on the stem while you pump, if you pull the stem through and lock the pump onto it, you shouldn’t have to hold it with one hand. Anyway, something i don’t think anyone has mentioned, if 125 psi is the maximum listed on your tire, you are probably over-doing it it by inflating to 125 psi all the time. You would probably be better served somewhere between 105-115. ---
**Author:** ![cmdrpiffle](https://avatars.discourse-cdn.com/v4/letter/c/b4bc9f/32.png) [@cmdrpiffle](https://boards.straightdope.com/u/cmdrpiffle)\ **Post date:** [August 20, 2014, 4:14pm UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/47 "2014-08-20T16:14:51Z")
> [@Colibri](#): > > **Moderator Warning** > > **samclem** has already cautioned you not to be insulting to other posters in this forum. This is an official warning. Do not do this again. > > Colibri > General Questions Moderator Guess I’ll have to take my encyclopedic knowledge of how to put air in a tire elsewhere… I’ll be the envy of all who struggle with such Herculean tasks… :smack: ---
**Author:** ![Mr.Nylock](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Mr.Nylock](https://boards.straightdope.com/u/Mr.Nylock)\ **Post date:** [August 21, 2014, 2:12am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/48 "2014-08-21T02:12:43Z")
> [@Clawdio](#): > > I’m still confused about having to hold the pump on the stem while you pump, if you pull the stem through and lock the pump onto it, you shouldn’t have to hold it with one hand. > > Anyway, something i don’t think anyone has mentioned, if 125 psi is the maximum listed on your tire, you are probably over-doing it it by inflating to 125 psi all the time. You would probably be better served somewhere between 105-115. That is usually an acceptable range. If you want to get super technical about ideal PSI you have to factor in body weight and look at a chart, and maybe consider road conditions as well. Your pump head seems to be worn, the pump should just lock on. It is very common for people to not press the head on enough before trying to lock it on, so you might want to try pushing it on a little harder before locking it. I would actually consider just drilling the hole to accept schrader valves(as mentioned by another poster earlier), there would be no down side to doing this, any decent LBS can do it in a few minutes if they are not busy. ---
**Author:** ![Spiderman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spiderman/32/230_2.png) [@Spiderman](https://boards.straightdope.com/u/Spiderman)\ **Post date:** [August 21, 2014, 2:21am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/49 "2014-08-21T02:21:32Z")
> [@Mr.Nylock](#): > > I would actually consider just drilling the hole to accept schrader valves(as mentioned by another poster earlier), **there would be no down side to doing this** , any decent LBS can do it in a few minutes if they are not busy. (Bolding mine) Depending upon the rim (both composition & design - are they aero rims, width, etc.) you could undermine the integrity of the wheel. I sure as hell wouldn’t want that as my front wheel on a pothole-strewn downhill. ---
**Author:** ![Mr.Nylock](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Mr.Nylock](https://boards.straightdope.com/u/Mr.Nylock)\ **Post date:** [August 21, 2014, 2:33am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/50 "2014-08-21T02:33:36Z")
> [@Spiderman](#): > > (Bolding mine) Depending upon the rim (both composition & design - are they aero rims, width, etc.) you could undermine the integrity of the wheel. I sure as hell wouldn’t want that as my front wheel on a pothole-strewn downhill. Based upon the wheel he has(assuming it is the original that came with the bike) I would disagree with that statement. When redrillling from presta to schrader it is such a small amount being taken away it would not have an effect on the strength. I have never seen or heard of such an issue as you describe arising from redriiling, do you happen to have a cite that discusses this? I would not want to inadvertently give unsafe advice. ---
**Author:** ![Busy\_Scissors](https://avatars.discourse-cdn.com/v4/letter/b/d78d45/32.png) [@Busy\_Scissors](https://boards.straightdope.com/u/Busy_Scissors)\ **Post date:** [August 21, 2014, 9:17am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/51 "2014-08-21T09:17:42Z")
> [@Spiderman](#): > > (Bolding mine) Depending upon the rim (both composition & design - are they aero rims, width, etc.) you could undermine the integrity of the wheel. I sure as hell wouldn’t want that as my front wheel on a pothole-strewn downhill. **Mr. Nylock** has the right of it - it’s a tiny amount of metal you’re removing. Make no diff to 99% of wheelsets. You wouldn’t do it to an aero rim, mind, as the schraeder valve is too short and you can’t typically get long schraeders [I’m sure they exist but I’ve never seen them available on bike inner tubes]. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [August 21, 2014, 11:46pm UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/52 "2014-08-21T23:46:07Z")
**Mister Rik** ,[a pump for you.](http://silca.cc/collections/floor-pumps/products/silca-superpista-ultimate-floor-pump) ---
**Author:** ![Mister\_Rik](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mister_rik/32/491_2.png) [@Mister\_Rik](https://boards.straightdope.com/u/Mister_Rik)\ **Post date:** [August 22, 2014, 2:11am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/53 "2014-08-22T02:11:17Z")
> [@running\_coach](#): > > **Mister Rik** ,[a pump for you.](http://silca.cc/collections/floor-pumps/products/silca-superpista-ultimate-floor-pump) As soon as I win the lottery. ---
**Author:** ![Mr.Nylock](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Mr.Nylock](https://boards.straightdope.com/u/Mr.Nylock)\ **Post date:** [August 22, 2014, 2:30am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/54 "2014-08-22T02:30:28Z")
> [@Busy\_Scissors](#): > > **Mr. Nylock** > You wouldn’t do it to an aero rim, mind, as the schraeder valve is too short and you can’t typically get long schraeders [I’m sure they exist but I’ve never seen them available on bike inner tubes]. You bring up a good point. If your tire is 700x28 or above you will have no problem finding a long valve schrader tube(they started becoming much more common after Target started selling Schwinn hybrid bikes with deep dish “Swift” rims that come with schrader valves). If you have a 700x25 or lower width tire it will be difficult to find tubes with a long enough stem for an aero rim. It is possible to use a 700x28 tube with a 700x25 tire, but it is very difficult to avoid bunching the tube. You should really go to a bike shop with your bike and ask them before you do anything; this forum kind of leads us all to make assumptions about the equipment you have in order to simplify things. ---
**Author:** ![Mister\_Rik](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mister_rik/32/491_2.png) [@Mister\_Rik](https://boards.straightdope.com/u/Mister_Rik)\ **Post date:** [August 22, 2014, 4:19am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/55 "2014-08-22T04:19:04Z")
I wish my digital camera hadn’t died, so that I could post a photo of my rims. I don’t even have a smartphone. If I simply need to pump up an already-mostly-inflated tire, it’s not much trouble to get the pump chuck to grab on. But if the tire is completely flat, the whole valve stem wants to disappear into the rim and tire, and it’s a bunch of work to get enough of it out so that the pump can get a grip. And the tires go completely flat because I don’t ride as much as I should. I haven’t gone for a ride at all this summer, which is what prompted me to start this thread. I said, “Damn, I need to get on this bike and go”, but first I had to go through all the convolutions of getting air back into the tires. This is the first bike I’ve ever owned that was equipped with presta valves, so to answer Mr. Insult up there ( **cmdrpiffle** ): Nobody fucking explained to me the differences between Schraeder and Presta valves. I’ve ridden bicycles since I was a child, and inflating a tire was always a very straightforward process, thanks to Schraeder valves. Nobody, even at the bike shop where I bought the damn thing, mentioned the additional steps necessary for working with a Presta valve. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [August 22, 2014, 5:02am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/56 "2014-08-22T05:02:53Z")
What additional steps? The only additional step is loosening the valve, but then you don’t need a valve cap on a presta so it’s not exactly additional. Any other problems you are having are to do with stem length, not stem type. I have the same problem with schrader valves on my mountain bike, they’re not long enough when the tyre is flat. Get some new tubes with longer valves and/or with stem nuts and it will once again be a very straight forward process. ---
**Author:** ![Mr.Nylock](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Mr.Nylock](https://boards.straightdope.com/u/Mr.Nylock)\ **Post date:** [August 22, 2014, 8:25am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/57 "2014-08-22T08:25:27Z")
> [@Mister\_Rik](#): > > This is the first bike I’ve ever owned that was equipped with presta valves, so to answer Mr. Insult up there ( **cmdrpiffle** ): Nobody fucking explained to me the differences between Schraeder and Presta valves. I’ve ridden bicycles since I was a child, and inflating a tire was always a very straightforward process, thanks to Schraeder valves. Nobody, even at the bike shop where I bought the damn thing, mentioned the additional steps necessary for working with a Presta valve. You could get 60mm presta valves to replace what you have and also use an adapter. If it makes you feel any better, the problems you are having are extremely common. You should be able to go into a shop and they can explain everything to you; the best time to go is mid afternoon or when it is overcast; at other times shops can be way too busy to spend much time with you. ---
**Author:** ![Mister\_Rik](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mister_rik/32/491_2.png) [@Mister\_Rik](https://boards.straightdope.com/u/Mister_Rik)\ **Post date:** [August 22, 2014, 11:36am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/58 "2014-08-22T11:36:19Z")
> [@Richard\_Pearse](#): > > What additional steps? Specifically, “burping” the tire - the bit in the video posted earlier about letting a bit of air out before attaching the pump. That’s not something that would have occurred to me, and nobody mentioned it. So all this time, I’ve been “forcing” the air into the tire, assuming it was just an annoying characteristic of Presta valves. On another note, I just realized that the first sentence of my final paragraph in my previous post looks like _me_ being insulting in GQ. I apologize, and blame my exhaustion after a long day. ---
**Author:** ![cmdrpiffle](https://avatars.discourse-cdn.com/v4/letter/c/b4bc9f/32.png) [@cmdrpiffle](https://boards.straightdope.com/u/cmdrpiffle)\ **Post date:** [August 22, 2014, 11:42am UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/59 "2014-08-22T11:42:03Z")
> [@Mister\_Rik](#): > > I wish my digital camera hadn’t died, so that I could post a photo of my rims. I don’t even have a smartphone. > > If I simply need to pump up an already-mostly-inflated tire, it’s not much trouble to get the pump chuck to grab on. But if the tire is completely flat, the whole valve stem wants to disappear into the rim and tire, and it’s a bunch of work to get enough of it out so that the pump can get a grip. > > And the tires go completely flat because I don’t ride as much as I should. I haven’t gone for a ride at all this summer, which is what prompted me to start this thread. I said, “Damn, I need to get on this bike and go”, but first I had to go through all the convolutions of getting air back into the tires. > > This is the first bike I’ve ever owned that was equipped with presta valves, so to answer Mr. Insult up there ( **cmdrpiffle** ): Nobody fucking explained to me the differences between Schraeder and Presta valves. I’ve ridden bicycles since I was a child, and inflating a tire was always a very straightforward process, thanks to Schraeder valves. Nobody, even at the bike shop where I bought the damn thing, mentioned the additional steps necessary for working with a Presta valve. Sorry for your angst and deep butt hurt at the world being so cruel so as not to explain how to pump up a bike tire. Must be rough being you ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [August 22, 2014, 12:22pm UTC](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738/60 "2014-08-22T12:22:53Z")
> [@Mister\_Rik](#): > > But if the tire is completely flat, the whole valve stem wants to disappear into the rim and tire, and it’s a bunch of work to get enough of it out so that the pump can get a grip. > > And the tires go completely flat because I don’t ride as much as I should. I haven’t gone for a ride at all this summer… A tire shouldn’t go _completely_ flat in one season. You probably have a leaky tube. Take it as an opportunity to replace it with a new tube _with a longer valve_. That should alleviate both problems. [Previous page](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738.md?page=2) [Next page](https://boards.straightdope.com/t/why-do-road-bicycle-tire-valves-have-to-be-such-a-pain-in-the-ass/695738.md?page=4)