How to fill a mountain bike tire


How to Inflate Mountain Bike Tire with Presta Valve

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!


What is a Presta Valve? Are Presta Valves Common on Mountain Bike Tires?

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 Valve

Currently, 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?

Benefits of Presta Valves:

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.


How Do You Inflate a Presta Valve with a Common Air Pump (Gas Station)?

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.

Presta valve adaptor

Here are the steps to inflate a presta valve with a standard pump:

  • Unscrew the screw on the tip of the presta valve.
  • Place the valve adaptor on the tip of the valve.
  • Engage the pump to inflate your mountain bike tire to your chosen pressure.
  • Remove the adaptor and screw the presta valve closed.

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!

Where Can I Get a Presta Valve Adapter?

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.


What Pressure Should You Inflate Your Mountain Bike Tire?

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.


How Do You Check the Pressure of Your Mountain Bike Tire?

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.


How Do You Inflate a Presta Valve without an Adapter?

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.

  1. Remove the 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.
  2. Unscrew the valve on the tire.
  3. Place the modified cap upside down on the tire and screw it down a few twists.
  4. Attach the pump and inflate.

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.

How to Pump Bike Tires

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All bike tires slowly leak air every day. Even if you’re an occasional rider, and you only take your bike down from the bike rack once a week, the tire pressure will still decrease. Before you ride, you should always check your tires’ PSI and, if needed, inflate them with a floor bike pump or a handheld pump.

What PSI should bike tires be?

On the sidewalls of your tires, you’ll see the manufacturer’s recommended pressure range for PSI (pounds per square inch). Different bike tires have different ranges, and narrow tires need more pressure than wide tires. The recommended PSI for different tires are:

  • Road bike tires: 80–130 psi
  • Mountain bike tires: 25–35 psi
  • Hybrid tires: 40–70 psi

Experienced cyclists can often estimate whether their tires need to be pumped by pinching the tire between their thumb and forefinger. The more accurate way of knowing when your tire should be pumped is by measuring its pressure with a pressure gauge; if the air pressure is measured below the recommended PSI, it’s time to pump.

First pump your bike tire to the middle of the range for the recommended PSI. You also need to take your body weight into account. Tires that bear a heavier rider need more PSI. Weather conditions and terrain also affect how a bike rides, so you’ll need to experiment with different PSIs to feel what’s most comfortable to you.

How to pump a tire with a Schrader valve

A Schrader valve is the type of valve you’ll find on car tires, older bike tires and mountain bikes. It consists of a metal pin in the center of a threaded valve, and a rubber cap that’s screwed onto the valve. Most bike pumps like those we reviewed have a dual head to accommodate both Schrader and Presta valves or a single head with an adapter.

If your tire has a Schrader valve

  1. Unscrew the rubber cap and put it someplace where it’s easy to find (like your pocket).
  2. Check the tire’s PSI using a pressure gauge or a bike pump with a built-in gauge, like the Topeak – Road Morph G.
  3. The pump’s Schrader head is the larger of the two openings. (It’s usually marked with the letter S.) Put the opening onto the tire valve, pressing down so the opening covers the valve.
  4. The pump head will have a lever that either pushes up or to the left or right. The lever closes off the Presta opening and locks the Schrader opening onto the valve.
  5. Keeping your eye on the gauge, pump until desired PSI is reached. As the pressure increases, it will take more effort to pump.
  6. Open the lever, pull up on the head, and screw the valve cap back on.

How to pump a tire with a Presta valve

A Presta valve is found on road bikes and some mountain bikes. It’s a slender valve with a nut at the top that is loosened and tightened before and after inflation. Almost all new bike pumps have a head with openings for both Schrader and Presta valves, or they have an adapter for switching from Schrader to Presta, like one of our top picks, the Topeak – Road Morph G.

If your tire has a Presta valve

  1. Unscrew the valve cap.
  2. Loosen the brass nut at the top of the stem. Press down on the stem, and if you hear a short burst of air escape, it’s loosened enough.
  3. Put the smaller opening of the pump head on the valve. If your pump has an adapter, switch the opening from Schrader to Presta.
  4. Flip the pump head’s lever to close off the Schrader opening and attach the Presta opening to the valve.
  5. Pump until the gauge registers the desired PSI.
  6. Flip the pump’s lever open and remove the head from the valve.
  7. Tighten the brass nut, and screw the dust protector back on.

Pumping bike tires at a gas station

If you’re out riding and your tires need air, you could give them a quick inflate with a CO2 injector, like the one we reviewed. But if you don’t have a CO2 injector in your bag, and you forgot your mini pump, then you can pull into a gas station and inflate your tires there.

If you don’t have a pressure gauge, ask the station attendant for one. Inflate your tires to optimal pressure in short bursts; a gas-station air pump has very high pressure, and you run the risk of popping your tire.

A gas-station air pump will only fit a Schrader valve. But if your tires have Presta valves and you don’t have a Presta valve adapter, there’s still a way to inflate them.

  1. Unscrew the Presta valve cap.
  2. Use scissors or a knife to cut off the pointed tip at the rim.
  3. Unscrew the valve stem.
  4. Turn the cut valve cap upside down, and place it on top of the valve stem.
  5. Screw the cap onto the stem.
  6. Put the pump head over the now-modified valve, and inflate your tire in short bursts.
  7. When your tire is at optimal pressure, remove the pump head, and unscrew the cap. You’re ready to ride again!

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Gene Gerrard, Writer

Gene has written about a wide variety of topics for too many years to count. He's been a professional chef, cooking-appliance demonstrator, playwright, director, editor of accountancy and bank-rating books, Houdini expert and dog lover (still is). When he's not writing for Your Best Digs, he's performing as a magician at the Magic Castle in Hollywood.

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Inflating bicycle wheels

Hello everyone! In this article, we will tell you how to pump up a wheel on a bicycle. We'll give beginners tips on getting the right tire pressure, talk about different pumps, and cover all the challenges you might run into. Go!

Tire pressure

To begin with, let's deal with tire pressure, since a lot depends on it, for example:

  • The quality of wheel adhesion to the road. nine0012
  • Freewheel
  • Driving comfort.

Bicycle manufacturers usually list the optimum bead pressure range, which can vary greatly depending on wheel width. For example, for fat bikes, the optimal pressure is from 0. 5 to 2 atmospheres, for mountain bikes from 2 to 4 atmospheres. Well, for road models, suitable pressure ranges from 5 to 8 atmospheres.

Based on this, it can be concluded that the minimum pressure is used where it is necessary to ensure good grip on uneven surfaces. Well, the maximum pressure increases the roll on a flat surface. Therefore, we recommend that you inflate the wheels according to how you plan to ride. If you don't have a particular preference, inflate at a medium setting for good rolling and traction. nine0003

The weight of the cyclist should also be taken into account - if you weigh little, then it is better to choose a pressure closer to the minimum, and vice versa.

Types of nipples

There are three standards of nipples used on modern bicycles. This is:

  • Shredder.
  • Presta.
  • Dunlop.

Schroeder is the best known type of nipple, which is also used in cars. Therefore, you will meet him on most bikes. nine0003

Presta is a thin nipple often referred to as a French nipple. These nipples are most commonly found on high-end bikes. As for the Dunlop standard nipples, they are very rare.

Some may think that each nipple requires a special pump. But this is not so - it is enough to purchase a regular car pump and an adapter for your type of nipple.

Bicycle pump options

If you don't have a car pump, you can purchase a bicycle pump. Most of the models on sale are universal, and support all nipple standards at once. Bicycle pumps are:

  • Compact.
  • Floor standing.

Compact pumps pump the wheels for a long time, but they take up little space. They can be mounted directly on the frame, and always carry with you, which is very convenient.

Floor pumps are more comfortable to use as they blow in more air with one push. In addition, they are equipped with a pressure gauge that allows you to control tire pressure. These pumps are an indispensable tool for road bike owners. nine0003

That's all for today. Thank you for your attention, if this article was useful to you, please like us or share it with your friends. See you again.

How to properly inflate bicycle tires

CONTENT OF THE ARTICLE:

    1. The first method. Schrader valve
    2. Second method. Presta valve
    3. Third method. Woods valve
    4. How to properly inflate a bike tube - video

No special effort is required to properly inflate bicycle tires. The only thing you need is the right tools. Using these techniques, you can easily find your valve type and choose the pump that is exactly right for your bike model, respectively, and learn how to properly inflate your tires. nine0003

Related: How to choose a bicycle pump?

First method. Schrader valve

1. Schrader valve, sometimes you can see the name American valve or automobile valve. The stem in this type of valve is surrounded by threads, you just need to press down on the stem with your thumbnail or other object such as a pen cap. If we compare Schrader valves with other types, then it is short and wide in diameter. Most often they can be found on cars, inexpensive or mountain bikes. To open this type of valve, you just need to unscrew the rubber plug. nine0003

2. Determine the recommended tire pressure for your bike. Often this indicator is located on the sidewall of the tire. Be vigilant and watch the pressure when you inflate your tires. It is recommended not to bring the readings to the lower line, as well as to the highest.


3. Position the pump. If you don't have your own yet, use the pump at the gas station, or borrow one from a friend.


4. Pump up the chamber. To do this, unscrew the rubber cap on the top of the valve and hide somewhere so as not to lose it. nine0003

  • Place the pump in the valve. If the lever is near the nozzle, make sure it is in the open position (parallel to the nozzle), snap the lever down all the way (perpendicular to the nozzle) when it is inside the valve. Be careful when you inflate tires.
  • Turn the lever up to remove the pump, then quickly screw the rubber cap onto the valve.


5. To deflate a tire with a Schrader valve, simply press the springy valve stem with your fingernail or other small object until all air is expelled. nine0046

Second method. Presta valve


1. French valve (Presta) or you can also find the name Sclaverand is usually found on road bikes with high functionality. Compared to a Schrader valve, this one is longer and narrower in diameter, and has an outer stem that is capped instead of being surrounded by a core.


2. Valve opening. Unscrew the dust cap to open the Presta valve. Then you need to loosen the brass cap on the valve stem a little, it will not be able to come out completely, and you will have to lift it up a little. If you want to check if the cap is loose, you just need to press on the valve stem, and if you hear that the air comes out in sharp gusts, then this is a sign that you can stop. nine0003


3. Calculate the recommended tire pressure for the bike. This is usually a relief mark that is located on the sidewall of the tire. Most often, these readings are written in bars or PSI. Do not let the pressure go to the bottom line, and also to the highest, which exceeds the maximum.


4. Pump installation. You can use the pumps of any gas station stations or take them from friends. And as an option - buy in the store "everything for bicycles".


5. Inflate tires. Open the Presta valve by unscrewing the dust cap and loosening the smaller brass cap.