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42

The main thing is that the Presta valve is thinner, and takes less of a bite out of the rim. This is quite important as the rims get narrower. Further, the Presta works better with hand pumps in that there's no spring that the pump needs to overcome to get air into the tire. Also, the Presta always has the fully-threaded body (which is possible with ...


33

The cap keeps dirt and rocks away from the valve, particularly the fragile release mechanism. It's not the end of the world if the caps are missing, but I suggest leaving them on. They don't take that long to remove and replace.


24

This primarily comes up as the pressures in the tires get higher. With lower pressure wider tires, Schrader makes the most sense, if only because you can hit a gas station for some air pressure. Presta makes more sense on higher pressure tires, since it allows you to pump in higher levels with a floor pump. Per the comments let me try and clarify. When ...


17

Nobody has noted this yet, so maybe I'm particularly clumsy. The caps prevent you from bending the somewhat delicate presta valve stem if, like me, you're fitting a fairly beefy lock between your spokes every day. I smacked mine pretty good after a groggy morning commute, and it bent the valve stem pretty severely. They're somewhat known for snapping off ...


15

smaller hole in the rim is good (presta +) schrader has piece that inserts into the valve (screws in) with a spring mechanism to seal it - these parts sometimes fail (schrader -) presta uses tire pressure to seal it (presta +) rocks can lodge in uncapped schrader and cause leaks (schrader -) presta does not need a valve cap to keep rocks out (presta +) ...


15

Those valve stems are too short for those deep deep rims you've got on there. You can tell just from the photos that the valve stem isn't sticking out far enough from the rim for the pump to fit all the way on it. Hence, it's not contacting the valve enough for you to inflate your tires.


14

That's a very hard area to patch properly (if its even possible), and I'd recommend putting a new tube in instead of trying to patch it. . I'd also check that the rim tape on the rim is intact and in good condition, cause otherwise if its busted, you're going to get another cut. Also, as pointed out by ChrisH in the comments, rough edges on the rim hole ...


13

Presta's main benefit is more about how the valve functions, in regards to getting pumped up to higher pressures. Because the stem of the valve needs pressure in the pump head to get high enough before it pushes the valve stem in, and start flowing air into the tire, when you try to get to 120 to 160 lbs of pressure it works better than a Schrader valve ...


13

It's a "dunlop" valve. Also called "woods". I used to see this years ago in BMX bikes. For best results we'd use to have a schrader adapter (google: dunlop to schrader adapter) so we could inflate with schrader pumps.


11

It should be straight out, perpendicular to the rim. Otherwise you risk damaging the tube. When the valve stem is at an angle the valve isn't free in the hole – it is trapped by the edges of the hole where they bind the stem. The edges of the hole may cut the stem which will be moving a little bit as the tire and tube flex over bumps and the like. There ...


10

That is a Presta Valve. Your pump, I am going to guess, is a Schrader Valve. You can buy a Presta pump from a shop or buy a $2 adapter.


9

I used to skin my knuckles every time I took the chuck off the valve. Then I figured it out (pain is a learning curve accelerator). Position the wheel so the presta valve is closest to you and pointed away from you. Use your thumbs on either side of the wheel to push the chuck straight off (toward the hub of the wheel). This prevents the presta stem from ...


8

They have one big benefit on road / commuting bikes - they stop the valve corroding and seizing due to the salt and crap they get exposed to. On a mountain bike, this isn't such a problem, as the salt gets washed off by puddles and mud (and you tend to wash your mountain bike more). That's been my experience in the muddy, wet UK, when the roads are salted ...


7

My conclusion after many years of using not two, but three types of valves is that the best is the one that results most practical for you, acording to type of riding, type of pumping methods available and of course the type of bike/tire/rims you are using. Neither valve type is absolutely better than other, but one of them may result better for your ...


7

It is for adjusting the suspension on a medium to high-end mountain bike (fork), hence the lack of 'Presta' option. Since you will be returning it, to keep the shop happy and get what you really need, consider getting: A track pump with gauge and aluminium body. Look for one with a well engineered head that does Presta and Shrader valves. The easiest ones ...


7

Schrader valves are more robust, this is the reason why you see them universally in use for vehicle tires. With Presta, you have to be more careful when putting in or taking off the pump nozzle or you might bend or even break either the rotating (locking) tip of the valve. You could also go to literally any gas station to pump air to your tires if you are ...


7

Schrader valves are stronger, for one. Breaking a weaker, smaller valve that has a (perhaps just in my experience) frustrating attachment mechanism for pumps on a $1,000+ fork would be unacceptable. Road Bicycles Schrader valves have at least one valid disadvantage on a road bicycle: their larger diameter is a deterrent for use because it reduces the ...


7

Yes. Slime makes some valve extenders for Schrader valves , and if you have a Presta valve you can use a Presta to Schrader valve adapter (and if you really want, you can attach a Schrader valve extender to that, since you can buy the Schrader valve extenders at Walmart or whatever) . Some companies (like Topeak) make Presta valve extenders as well: ...


6

I've also had fewer issues with crap clogging the valve with presta valves; as long as you remember to spin the valve closed you don't need a valve stem cap. This is particularly important if you're riding in mud or dirt. I run presta on both my road and mountain bikes for this reason.


6

Because you only fill one tire at a time. The adapter screws off and can be used on either tire if needed. It can also be easily stored with your patch kit, so it doesn't need to be on the bike. I only keep one around in case I get stuck with only a schraeder pump at my disposal.


6

You could always buy some new tubes with the valve set at a 45 degree angle. Schwalbe sell them for £5/6 depending on the size you need. Easiest way I'd say and saves you faffing about drilling holes or screwing valve extenders on and off.


6

You don't need the nut, really (and its rather abnormal on Schrader valve tube) -- a lot of people just throw it away. The point of the nut is so that the tube's stem doesn't go into the rim when you're trying to inflate the tube and the stem doesn't move around when you're trying to pump the tire. Note that the tube can only go significantly into the rim ...


5

Keep the cap on to protect the valve from accidental damage, dirt, salt and oxygen. There is a bit of rubber inside the Presta valve: Leave the valve cap off and oxygen in the air gets to the rubber causing it to perish. This problem will take time to develop, however it will do regardless of where you live, where you ride and how often you clean your ...


5

On my MTB I leave them on to keep mud from crudding up the works. On road and commuter bikes they are useless and I toss them.


5

There is a valve in the floor pump, yes, so it is supposed to press in the presta valve the whole time it is attached to it. I too have seen the problem you refer to in the comment on @Useless's answer - diagnosis has always shown this to be down to the presta valve either catching on the side of the pump fitting or just being stiff and refusing to budge. ...


5

I swapped out both tubes on my mountain bike with Presta (less chance of crap getting in to the valve and it means I can carry the same CO2 inflator as I do on my road bike) and got the bushings - once they were in I've had zero issues with the valve stem. I'd definitely recommend putting one in since there's the chance that the valve stem could rub against ...


5

Yes, the holes are different sizes. 6mm and 8mm, from memory. The hole size matters if you have skinny rims as 8mm out of a 20mm rim is a lot compared to 8mm out of a 40mm rim. But you already have valve holes. In theory putting a presta valve in a Schrader-size hole matters, in practice it doesn't. The base of the valve is where you'll see any effect from ...


5

What you need is a valve core (provided the stem is threaded to take a removable valve core) [The question is, what happened to the original one?] The cheapest option and easiest option is to just buy a new tube.


5

Get a Dremel (rotary tool) with a cone shaped sander (e.g., the 3/8 in bit shown below). The sander will need to be wider than the diameter of a bicycle Schrader valve stem. You will use this to form a hole in an appropriately sized patch (i.e., a patch larger enough to have sufficient material on all sides of the hole). The hole needs to be the perfect ...


5

Answer: Yes you can. Woods/Dunlop valves have a nominal hole size of 8mm, identical to a Schrader/Auto valve. For completeness, a presta valve uses a 6mm hole. Reasons not to - authenticity of an antique bike, or maybe having to carry a second pump head/fitting if both tubes have different valves.



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