Schrader or presta?
 

This may seem like a naive question. I was bikeless for many years till I had to give up my driving because of age. I now use an electric trike to get around; but to get to the point, when I was young there were only shraeder valves. If there was such a thing as a presta I never heard of it. Can someone give me a quick tutorial on the advantages and disadvantages of each type?

Presta vs Schrader valves by Jobst Brandt

Schrader is probably "better" in general because it's more common, so they can be filled at gas stations or with Schrader only pumps.
Also, some people have trouble with presta valves which can break with a lot of sideways force.

However most higher quality bikes use presta, although most rims can be drilled to accept Schrader..

They've been around for decades. Started in Europe. FYI: All my bikes have had presta valves.
https://www.youtube.com/watch?v=9byRp9e2USU

About the only advantage that Schrader valves have over presta is that there chucks for filling the tires with the valves are widely and readily available. People are also familiar with them.

Prestas do have an advantage in the manner in which they work over Schraders. A Schrader valve has to be held open for air to flow past the valve. If the pump head doesn't mate properly with the valve stem, air can leak out of the hose being used to fill the valve but it can also leak out of the tire being filled. If you use a pump on a Schrader valve and hear any leakage of air, the air is coming out of the tire you are trying to fill. Air can flow in either direction as long as the valve is being held open. All your efforts to fill the tire are for naught until you stop the air leaking out of the valve.

And additional problem is that when you press on the Schrader valve with the chuck, the valve will backfill the hose to the pump if there is no pressure in the hose. This isn't a problem for compressor systems since the hose is pressurized. But for a hand pump with an unpressurized hose, you've just lost some of the pressure in the tire to fill the hose and any parts of the pump that are open to the tire. You have to pump more to make up that deficit.

Prestas only open when air pressure is pushing against them. If the pressure on the pump side is higher than the pressure on the tire side, the valve opens. But once the pressure on the pump side drops below the pressure on the tire side, the valve closes and preserves the pressure in the tire. It's a check valve that only allows flow in one direction. If you hear leaking at the hose, the air is coming out of the hose itself and not out of the tire.

You can make a Schrader valve act as a check valve but you have to put about 25psi more pressure on the pump side than the tire side to open the spring on the Schrader that holds the valve closed.

If you are using a compressor to fill your tires, it doesn't make much difference. If you have hand pumping your tires, it can make enough difference to make the presta advantageous.

Thank you for the helpful replies. That youtube link at least gives me the idea and Cyccommute pretty well covers the advantages and disadvantages of each type.

I like presta because I don't lose air when putting the pump head on/taking it off. Every bit of air matters with road bike tires since there isn't a lot of volume in them.

And if you have Presta valves, you can always get an adaptor for a couple of bucks.

I've noticed that most pumps come with an adapter as part of the package.

If you have very narrow rims (which are thankfully becoming rarer even on racing bikes) then presta valves are preferable because the hole is smaller and leaves more of the already minimal material. If you have rims wider than ~13mm, and especially if you don't have high pressure narrow tires, then there is no advantage to presta, and Shchreader is more convenient.

My winter beater has Schrader valves on its tires and my three-season bike has presta valves. My floor pump handles both without needing to make any changes, but my portable pump needs to be reconfigured for the different valves. That's about the only aggravation I have experienced, and I personally can't see any reason why I would go out of my way to select one valve over another if I were given a choice. It seems like a big-endian/little-endian war to me...

For me it depends on how I'm inflating the tire.

If I'm using my air compressor, Schrader wins in a walk. It's much, much faster and easier.

If I'm using any kind of a hand pump, I have to use a chuck that threads onto the valve stem. I have to be much more careful threading a Schrader valve so it will press the little finger that opens the valve. So when using a hand pump, I prefer Presta valves.

Presta can go in your larger Schrader/ Dunlop-Woods stem hole , but you have to enlarge a presta hole to do the reverse.


Race style bikes have narrow rims , So they have the smaller hole .

Presta is the stem type in the glued on Traditional sew up tires the Pros race on still.

Presta also makes it easy to take air out of your tires if you want to lower the pressure in them for some reason. (Extra traction.) While it's possible with schraeder, it's harder and often requires a small pointy object.

I've read that you can buy a Presta to Schrader adapter. Can you leave that adapter permanently on the Presta stem (and capping the valve with the Schrader cap?).

Schrader or presta?
 

You can leave the adapter on, but I don't think the cap will screw onto it.
I believe many roadies ditch the cap of presta valves, and only use them when folding empty tubes.
Those plastic caps weigh a ton too ;)

Yes, a Schrader cap on a from Presta to Schrader adapter* works Fine .

* in brass and aluminum.

Thank you gentlemen. Now I know what to do if I get a Presta valve drilled rim!

I guess that you're right but geeze.

Presta.

Nah, it's not the weight; they're not aero enough.

My personal preference is for Schrader, simply due to being more rugged. I've had stem and valve failures on Presta tubes, none on Schrader. With that said, I wouldn't go out of my way to drill out any of my rims that use Presta, and since I became conscious of being much more careful with them, I haven't had any failures.

Presta for high pressure low volume tires. Schrader works fine for other way around. Adapters okay for if needed at times.

I vote for presta.

Is this a vote, like in Vermont or more like a caucus, like Iowa?

I actually had to go down to check all of our bikes in order to be sure and discovered that the Grouch household is, at this moment, 100% Presta. My most recent bike purchase came with Schrader valves but I have installed rubber grommets to convert the rims to Presta. So if this is an Iowa style caucus, my vote could be changed real easily.

If there are any Schrader valve people who, like me, would like to change their allegiance, PM me and I'll send you a free pair of Presta valve Grommets.

My city bike has a Schrader front and a Presta rear (because I have a custom wheel on the back) and the difference, in real life, is zero. My Joe Blow has a simple adjustment so it is a breeze (pun intended) to fill both up to pressure. The Presta takes a second or two longer because it needs to be unscrewed.

I think Presta is preferred by the cycling community because in the past it was far superior for cycling use for a number of reasons. But with modern floor/frame pumps it has lost any advantages.

One thing that may give Schrader an advantage is for touring. Sometimes a long distance cyclist may need to replace a tube, and KMart/Walmart carries only Schrader. But for city types like myself that's not an issue.