If you are having problems inflating your tire using a Presta valve, chances are you are getting frustrated and looking for answers…
Why won’t my Presta valve inflate?
If your Presta valve is not inflating, the first thing to do is to check how it is interfaced. Is the pump head seated well on the valve? Also, hold a finger close to make sure that air isn’t leaking out as you attempt to pump.
If it is, then it’s either not securely fitted, or there may be some sort of obstruction or a broken valve. Finally, it could also be a serious leak, so that the air is going into the tire but coming right back out of it.
You can put a little soap on suspected leak areas and when you pump, bubbling will confirm if the air is coming out that way.
Why can’t I pump air into my bike tire?
There are lots of reasons why pumping might not work. It could be the head that you are using, for instance, as the wrong head will not be properly compatible.
Beyond this, the valve stem could be broken, the pump might also be damaged, or the tire might be compromised enough that the air is going back out of it. Usually, it’s going to be a matter of the fitting, however, so check the head to make sure that air isn’t coming out when you pump.
More often than not, unless the tire is damaged, it’s usually just a poor fit from the head, which you can easily switch and fix.
Why are Presta valves so difficult?
It’s not so much that they are difficult, but simply very specialized. Presta valves for bike tires have a very small diameter for you to work with, so if you are trying to use anything besides a standard bike pump, then it may well be slow-going if it works at all.
Keep in mind, however, that the cap is quite important after you air it up – if you’ve lost this, then that will cause the air to escape quite quickly and your tires will not stay aired.
How tight should a Presta valve be?
The best option is ‘finger tight’ and we’ll explain this. When you are inflating the tire, tighten the nut just barely enough so that it feels secure, but not overly so. After you’ve inflated it, then go ahead and tighten it with your fingers again, as hard as you can without making it difficult to remove later.
This is why it is best to use your fingers – unless you have a grip of steel, this shouldn’t overtighten them so that if you need a roadside repair you won’t have to worry about the nut being stuck.
Do all Presta valves have removable cores?
No, some Presta valves will have removable cores, while others will not. Schraders do, but with Presta, you will only see them some of the time. The ones that DO have removable cores, however, can be quite handy.
You can use them with a tubeless setup if you like, just be sure to add a little sealant to secure them in place.
Are all Presta valves the same size?
While the valve portion will be uniform across the board, you will run into different lengths of Presta valves. This is not a problem, with the exception that you’ll want to make sure that the valve is long enough to go through the rim and to allow you to attach the pump to it.
In most cases, this won’t be a problem, and aside from the length variations your Presta valves are all the same. This provides the versatility of use, while still maintaining a standard for pumping air wherever the Presta is situated.
Can you pump the Presta valve at a gas station?
Not without ‘hacking’ your Presta valve, unfortunately. Gas station air pumps are designed to fit Schrader valves, but you could conceivably use one anyway – but you’ll need something sharp. The trick is to cut off the pointed tip end of the valve on your rim.
This would allow you to inflate the tire, but after that, the cap isn’t going to fit, so you’ll eventually end up losing air fairly quickly. So, while you could technically do it, filling your tires at the gas station is not a good idea unless that particular station advertises compatibility with Presta valves.
What is the screw on the Presta valve for?
The screw on the Presta valve is called a ‘jam nut’ or an ‘installation nut’. The way it functions is that it keeps the valve from sinking when you go to pump air in the tire.
Once the pump is in place and working, then the air pressure will keep it up and you can remove it, but don’t do this beforehand or you’ll have problems – it’s there for a reason, after all!
Do Presta valves hold air better?
Yes, Presta valves hold air very well, as the growing air pressure inside the tire will actively help it to seal itself. They are also quite lightweight, which helps to maximize the performance of your wheels, as this reduces the overall rolling resistance.
Another Presta perk is that these same valves will work with adaptors so that the tire will work well on other rims as you like, should you decide on a rim upgrade. All in all, Presta is very good at what it was designed for, and that’s why it’s a cycling standard.
Are all Presta valve cores the same?
Yes, at the core, all of the Presta valves are the same. While you can find them in a wide range of configurations that look very different, the core itself is designed to be a standard variety, so that it may be used and interchanged in several different valves.
So, if you want to change out a Presta core to another Presta valve, then you don’t need to worry. They are all designed to the same standard when it comes to the core. As long as you’re using it in another Presta valve and you do the swap correctly, then you shouldn’t have any trouble.