I headed off from my house one Saturday early in my biking career, drooling with excitement for the mountain bike ride I’d been awaiting all week. Then, before I had reached the trailhead, I noticed my rear tire was significantly low. I felt like I was riding through mud – on the pavement! Remembering a gas station with an air pump on my way to the trailhead, I figured I could easily pump up my tire without a wasted trip back to my house.
But, when I tried to inflate my mountain bike tire… AAACK! Foiled! The gas station had a standard car pump and, new biker that I was, I forgot my bike tires have a presta valve. A week of hungering for a mountain bike ride… RUINED! All because of a puny little valve. Oh, the angst. Do NOT let this happen to YOU!
Unless you grew up biking, most of us are so familiar with car tire valves, we assume it’s the only type of valve. In truth, car tires use what’s called a Schrader valve. It’s about the diameter of a pencil and has a tiny “button” in the center that, when pressed, allows air in or out, but holds air pressure relatively steady when not compressed.
Presta valves, on the other hand, are significantly skinnier than Schrader valves. They don’t have a button in the center of the valve and instead have an attached screw mechanism at the tip. When screwed closed, it holds air pressure in the tire. When unscrewed, you can pump air in or release air out.
Presta ValveCurrently, presta valves are the most common type of valve on high-end mountain bikes. Racers and high performance cyclists prefer them. They’re becoming increasingly common – even on mountain bikes on the low-end of the price spectrum.
Why, you ask. (Perhaps with a significant number of swear words as you kick your flat mountain bike tire or throw your useless Schrader pump.) Why use an uncommon, obscure valve that doesn’t fit a standard pump? Is it just to make mountain bike newbies suffer? Why? Why?
No, it’s not just to frustrate you.
Presta valves are generally more reliable and allow pumping your tires to a more precise pressure. By virtue of design, all Schrader valves release tiny amounts of air over time, requiring occasional “topping off”. Having a cap on the valve can significantly decrease the air loss, but it still means, at any given moment, your tire may not have the pressure you pumped it to.
A casual mountain bike rider may not know what pressure they should be riding or even notice when the pressure is off. But for high-speed riders, tire pressure can have a significant impact on speed, race performance and riding safety.
The screw on the tip of the presta valve allows a rider to close off the tube at the desired pressure and not require a cap. Barring an unnoticed leak or a puncture during a ride, the tire will now reliably hold the pressure you want.
You can inflate a presta valve with a common air pump, such as at a gas station or portable air compressor.
However, you need an adaptor that’s ridiculously small in size but huge in importance: a presta valve adaptor.
Here are the steps to inflate a presta valve with a standard pump:
Since more and more mountain bike tires use presta valves, most bike pumps are either universal (meaning one hole works on both presta and Schrader valves) or they have two separate holes, one for each valve type. However, you should always carry a valve adaptor when you ride for situations when a standard pump is the only option. Some cyclists do this by keeping a valve adaptor screwed on their tire valve all the time. Just make sure the valve is screwed closed before putting the adapter on!
Presta valve adapters are extremely tiny and portable.
This also means they’re easy to lose. The good news is they’re fairly cheap. I usually buy a handful at a time and keep one in my garage bike tools and one in my portable tool kit for rides. Having one in your glove box isn’t a bad idea, either!
All bike shops sell valve adapters and some general sporting goods shops and hardware stores carry them as well. You can also buy valve adapters online easily and cheaply.
This simple question actually does not have a straightforward answer. The simple rule is to refer to the tire manufacturer’s specs on tire pressure that are printed on the sidewall of your tires. Consensus of riders is that mountain bike pressure should be 30 psi on the front tire and 33 psi for the rear tire. This information should serve you well if you have only a casual interest in mountain biking and are doing entry-level to intermediate trails two or three times a month.
However, if you spend a significant amount of time on your bike (and an equally significant amount of time dealing with pinch flats, blowouts or skidding out on corners), you’ll want to dive deeper into the science of bike tire pressure.
DIY Mountain Bike has a fabulous, in-depth article and survey results examining appropriate bike tire pressure.
The fastest and easiest (and cheapest) way to check your tire is with your hand. When you squeeze it, it should be hard in the center with only a tiny bit of give farther out on the tire near the treads. A hand test, however, is – not surprisingly – not very accurate!
If you want to be precise, a tire pressure gauge will be necessary. But be warned: tire pressure gauges are notoriously unreliable and the sensitive sensors are easily broken. For my recommendation, read my tire pressure gauge product review.
If you’re in a pinch (perhaps literally!), and you don’t have a universal pump or a valve adapter, you can modify a tube cap to create a functional adapter using a presta valve CAP.
Find the place on the valve cap where it gets smaller. Cut at that spot with scissors or whatever you have that will do the trick. Throw the tiny tip away.Remember to screw the tire valve shut after inflating! I know you’re tired of hearing that, but it’s important.
Now that you know everything you need to about how to inflate a presta mountain bike tire, you’ll never find yourself hungering for a ride and find yourself deterred by a standard tire pump!
And don’t forget to screw the presta valve closed…
Professional writer Kat Jahnigen was 2 miles from the nearest village – and roughly 2,310 miles – from the nearest English-speaking town – when her bike tire burst. At that time, she was a college student on a bike trip across the desolate, rocky island of Crete. It suddenly occurred to her that it would’ve been good to learn some basic bike repairs before setting off on a solo bike trip.
Check out Kat’s website WriteHire at writehire.net.
Learn how to inflate presta valves in just a few simple steps.
Image Credit: Kelly-anne Leyman/Hemera/Getty Images
You'd think inflating a bike tire would be pretty simple. That is, until you take a look at your bike's valve. Enter, intimidation.
The most common type of bike valve is called a Presta, and it's a long, cylindrical piece of metal that sticks out from the bike's tire. It has a small tip at the end.
Fortunately, you can pump up a Presta in just a few simple steps, according to cycling coach Garret Seacat, CSCS. All you need to fill your tire is a compatible bike pump (more on that below).
Check out this video and step-by-step instructions to learn how to inflate a Presta valve. Then get ready to ride your bicycle flat-tire-free.
Find and Unscrew the Valve CapThe valve should be on the inside of your tire. Unscrew the small point (aka nut or cap) near the top of the valve. It will turn in a circle and move upward until it's at the top of the thread. Don't force it past this point, recommends Seacat.
Once the cap is in the top position, press the valve. If you feel a little air coming out, you're ready to go.
Connect the pump head to the top of the valve and lock it in place. (Some pumps require pulling a lever while others involve pressing a button at the end of the hose, he says.)
Start the flow of air, monitoring the tire pressure as it inflates. Continue pumping to the pressure measurement or PSI listed on the tires, Seacat says.
Unlock the head of the pump and remove it from the valve. (Reverse the motion you used to attach the pump.)
Make sure to screw the nut of the valve back into place, Seacat says.
Tap the top of the valve. If no air comes out, your job is done.
Misplaced your cap or need a new one? You can buy a replacement to keep your tires inflated and valve damage-free
While most bike pumps are compatible with Presta valves, some aren't. Scraders are another common type of pump and fit with (you guessed it) Schrader valves. (You can check your bike pump's manual or online product description to figure out which kind of pump it is.)
Fortunately, if you have a Schrader pump, you can still use it to inflate a Presta valve — you just need an adapter. These are super easy to install (generally all you do is screw them onto the valve) and inexpensive to buy online.
The Best Presta Valve Adaptors
com, $5.99 for 5)Related Reading
A nipple is a small part on a bicycle that is used to inflate bicycle wheels. When working with nipples, the main subtleties should be taken into account.
In cycling terms - and just to be very clear, those are the only terms we'll cover here - "nipple" is the word used for the little nut that attaches the end of each spoke to the rim of your wheel. . Each nipple is a small brass or aluminum cylinder with internal threads, a conical or spherical head that sits inside the rim, and flattened areas at the outer end of the cylinder (pointing inward towards the hub) so that they can be gripped and tightened with a special tool (spanner). spoked key or "key"). nine0005
Nipples work by applying tension to the spokes, the inner thread of the nipple corresponds to the thread of the screw at the end of the spoke. Tightening or loosening a nipple increases or decreases spoke tension, and achieving the correct tension to make the wheel spin "correctly" is one of the essential skills to build and adjust wheels.
Brass nipples are stronger. Some nipple manufacturers will tell you otherwise and they will have data to back it up. The problem with this data is that it measures brand new nipples in a lab setting. The problem is that when assembling the spoke does not rub against the rim, and there is no dynamism in this. We pre-prepare the discs to prevent the nipple from being abraded by a sharp protrusion, lubricate the nipples with grease and use a spoke preparation agent to lubricate and insulate the spokes and nipples, but the corrosion resistance of brass is better. nine0005
How to choose spoke nipples? Brass or alloy, which is better? This is a common question asked by both novice and experienced riders. Generally speaking, brass nipples are stronger and heavier, while alloy nipples are lighter and come in a variety of colors.
Brass nipples typically weigh about 1 gram each, while alloy nipples weigh about ⅓ grams. It may not seem like much, but some wheelsets have up to 72 nipples, and these are located near the outside diameter of the wheel, where rotational weight is more critical. nine0005
Brass nipples are not alloy-coloured, but are available in black and silver. You will notice that the black brass nipples don't look as bright as the black alloy nipples and they discolor more easily. On the other hand, alloy nipples can be anodized, so they come in a wide variety of colors.
If you use standard 12 mm long nipples with a traditional head, the brass nipples are more durable. Raised head alloy nipples (such as double square or hex heads) have significantly greater shear strength due to the large head (and no groove). Most oversized 16mm nipples can achieve full thread engagement, while traditional nipples can only get engagement at best. nine0005
Alloy nipples have less friction when turning onto steel spokes than brass, so they tend to build up more easily and builders don't have to struggle with spoke winding (twisting).
The alloy is slightly softer than brass, so the nipples round more easily. 4 way external nipple wrench or internal nipple tool when using hex, double square or DT Squorx nipples is very useful to prevent damage to nipples during construction
In most cases, brass nipples do not corrode as much as alloy nipples. There is more galvanic corrosion between carbon and alloy, so only high quality alloy nipples should be used. The high quality alloy nipples are given a special anti-corrosion treatment and salt spray tests show better results than nickel plated brass nipples.
It is often easier to rebuild a wheel with brass nipples because over time they don't warp or become as brittle as alloyed ones. Alloy nipples can work well, but look for higher quality tools and raised head nipples if you want more trouble-free building. nine0005
When building wheels from scratch or replacing broken spokes, there are a few things to keep in mind when it comes to choosing nipples, namely thread diameter, materials and nipple length.
Take a flathead screwdriver with a blade that fits the spoke nipples well (blade width and blade thickness).
Use a tool with a cutting disc to cut a slot in the middle of the blade so that the blade can fit into the slot on the spoke nipple above the projecting end of the spoke. Apply a drop of penetrating lubricant to the threads on the protruding end of the spoke and another drop to both the broken part and the other end of the spoke to help unscrew the broken nipple. nine0005
Step-by-step instructions:
While most of you almost certainly know how to inflate tires on your bike, this is another one of those simple tasks like changing the inner tube or using clipless pedals that can be quite confusing to a beginner. nine0005
There are many different types of pumps, inflators, valves, pipes and tires - all of which can be a real nightmare if you come to this for the first time.
If you ride a road bike, the Presta valve is pretty much the only type of valve you need to worry about.
Presta valves are easier to inflate than Schrader valves, especially with small capacity hand pumps, and this also means smaller pumps do not require the built-in spring depressurizer in the Schrader valve. nine0005
One of the clever parts of the Presta valve design is that even when the top section is open, no air will escape from it unless it is pressed down. This means that even if you forget to re-start the tire after you've filled it up, you shouldn't find yourself with a hole again 500 meters down the road.
The first step is to unscrew the head of the Presta valve. It unscrews counterclockwise and you can see it move up along the small central spindle. Make sure it is fully open. nine0005
Then attach the end of the pump to the valve head. As I mentioned earlier, make sure you are using a Presta.
In addition, you need to make sure that the pump head is securely attached to the valve, otherwise the air will not enter the tube properly.
It must be a sealed system to be most effective. How you create this seal depends on the pump. Many will have a lever that you raise to secure the pump head, some will have a screw chuck. nine0005
Watch your track pump gauge while you inflate your tires. If you exceed the recommended maximum pressure, the results can be harsh, explosive and costly.
After that, simply inflate the tire while watching the pump gauge and make sure you don't over-inflate the tire (most tires will have a recommended pressure range printed on the side).
While you might consider lowering the bottom number a bit to soften the ride or add a bit more grip, going over the top number can cause the tire to come off the rim, which can result in tire, tube, or tube scrapping. and rims. nine0005
You can usually find a happy medium between the two through experimentation and depending on your weight, where you ride and how much cushioning you want the tire to provide.
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The nipple, at its core, is a nut, the essence of which boils down to the ability to pump up the wheels.
And, oddly enough, it is he who is the undeniable link between the cyclist and the motorist. Why? The roots of this story go back to the 19th century.
Initially, all vehicles had wooden wheels. And only at the end of the 19th century, a certain John Dunlop came up with the idea that inflatable rubber wheels are much more practical and convenient. Therefore, he developed special protectors for his son's bicycle, inside of which there was air. Periodically, the wheels required pumping, for which the nipple was invented. Thus, a new word appeared in the history of transport development. nine0005
These parts began to be used not only for bicycle, but also for car wheels. Over time, varieties of these miracle nuts appeared. We will talk about them.
In some information sources, a bicycle nipple is also referred to as a spool valve. However, these are slightly different concepts. The spool is that part of the nipple that directly supplies air to the tires, moving in a straight line.
But for convenience, in this article we will identify these concepts. nine0005
| Automotive | A.k.a Schroeder Nipple. As the name suggests, this spool valve can be used on both bicycle and car wheels. Moreover, the automobile spool greatly facilitates the task of pumping up the wheels - the auto pump tube fits perfectly into the cap. The diameter of the spool in the standard is 8 mm. It is put mainly on mountain bikes and downhills. |
| Bicycle nipple nine0125 | Also known as Presta. The most popular among his fellows. Such a spool valve keeps the pressure in the tires better, better designed. However, it is almost impossible to use a car pump with it, you must have either a special nozzle or a pump designed for bicycles. Yes, and this type must be handled with the utmost care: the Presta bicycle valve is equipped with a very fragile valve that is easy to break even when pumping the chambers. Therefore, manufacturers often make it screw-in. Diameter - 6 mm. nine0125 |
| Dunlop | A cross between the other two types of spool valve. Outdated model. It is installed only on children's bicycles and on retro bikes. The hole diameter, like that of an automobile counterpart, is 8 mm. |
In everyday life, a cyclist pays attention to bicycle nipples only when the wheels need to be pumped up. Therefore, the topic of correct handling of the spool valve and the pump should be given special attention. nine0005
Automotive nipple
If this piece of technical thought is installed on your iron horse, then inflating a tire will not be difficult either in the garage or on the road (if required). The fact is that the valve on such a device is universal and any pump that is at hand can be used for it.
What are we doing. The autonipple is equipped with a special cap that keeps the pressure in the tires. It must be unscrewed and put in a conspicuous place.
Now we install the pump head and fix it with a clip (the clip is parallel to the nipple). Now gently blow air into the tire. The wheel rim always indicates what pressure is acceptable for a given bike. Try not to go beyond these designations, watch the pressure gauge on the pump. Ready! We release the clamp, remove the pump and twist the cap into place. Everyone, you can move on. nine0005
Presta
This spool is found on all sport type bikes. It is slightly smaller in diameter than the autonipple, but its length is much longer - from 42 to 80 mm versus 40. The main feature of Presta is that the valve stem is outside, not inside. And a special nut is also attached to the cap, which additionally traps air in the tires. You should be aware that for pumping air you will need either a bicycle pump or a car pump with a special hole. The standard entry is no longer suitable. nine0005
How to inflate a wheel. We start, as always, by unscrewing the cap and putting it in the tactile zone (so as not to lose it).
Now you need to unscrew the lock nut. And here you need to make a reservation: there is no need to completely remove it from the rod. It is enough just to achieve the release of the rod. It's easy to check - press the valve with your finger and if at the same time air comes out of the wheel, then the job is done. Well, then the process is absolutely similar to the previous, automobile nipple: we install the pump, fix the clamp and in portions, following the monometer, we supply air to the tire. Made! nine0005
Dunlop
Surprisingly, this type of valve looks very similar to an autonipple, but functionally it looks like Presta. Dunlops are almost non-existent on modern bikes, but if you're the lucky owner of a retro bike, you should follow the instructions for the Presta valve to inflate the wheel.
