My son recently got a really nice specialized bike used. It came with presta tubes on it, and a few extras. Last night he called me in the middle of the night to come pick him up because he had a flat and he could not get the pumps on campus to work with his tubes.

He said he could have probably ridden home on the low tire, but he was trying to fill it up but instead the pump kept releasing more and more air.

I personally see no benefit to presta valves, but there has to be some... right?

For casual riding there's no benefit to a presta valve over schrader. If he were using the bike for heavy intensity MTB, the only benefit would be a smaller valve hole in the rim, creating a stronger hoop.

If the rim is wide enough, you can simply drill the valve hole open and use a schrader valve, assuming he's got a rim diameter that schrader tubes are made for.

Presta valve cores are removable, so you can remove the core to put sealant in through the valve without unseating the tire bead, and can connect a pump to the valve stem without the core in to inflate quickly to seat tire beads on diffucult-to-seat tires/rims.

https://sheldonbrown.com/brandt/presta-schrader.html

In the past, sports and racing bicycles used Presta valves because they are slender and enabled racers to inflate tires with a simple pump with attached chuck (pump head) and no hose. Presta valves are easier to pump than Schrader, because they have no valve spring to overcome. Although a valve depressor for Schrader valves can alleviate this, it requires a check valve, impractical to house in lightweight pump heads.

The small diameter of the Presta valve requires a smaller hole in the rim, whose size is important for narrow rims where cross sectional strength of is significantly reduced by a stem hole. In narrow rims, clincher tires also leave insufficient space between tire beads for larger Schrader valves.

Schrader cores are also removable.

casual rider ? drill the hole out and replace it with Schrader tubes, or just carry an adaptor, they screw on, use then screw off.

i assume it has tubes though ?

very narrow rims on road bikes mainly

mine are all presta

It's marginally easier to let air out the tire with a Presta valve which is handy if you're a mountain biker who likes to mess with tire pressures.

I'm a mountain biker who likes to mess with tire pressures and I've drilled all my rims and use Schrader valves instead as needing a tool to let out some air is a fair trade-off considering it's a superior valve in every other way.

Everything here is true of schrader valves too.

I never thought of the rim hole being a different diameter. I think for now we will invest in a presta specific pump for him.

Very casual rider. He only uses it as transportation to and from school/work.

It is a Specialized Sirrus X2.0, it does have tubes. Looking at the images of the product page I am not certain the rims he has are the stock rims, I think his are more narrow.

There are none in my opinion

The main one for me is: when running low tire pressure on my 26er mtb, I had more than a few incidents where the Shrader valve got pulled into the rim or the side was cut by it. Presta is not necessary for casual.

You have some options. First, you could just thread these adapters onto the presta valve(after opening the presta valve stem cap) and use a schrader-style pump, that's your cheapest option but I've come across a very few schrader pumps that don't work with this. They were unable to pass air to the tube. Tell him to be sure to close the presta valve after filling.

If he carries a backpack or has a free bottle cage mount on his bike, , he can carry a compact pump , they often will work with either valve. Full disclosure that it can take quite a few pumps to get the tire to the proper pressure.

My favorite thing about Presta valves is that you can remove the cores, and swap in Clik valves. Those are better than either Presta or Schrader with the minor downside that it's even harder to find a pump that fits.

Clik valves are backwards compatible with presta compatible pumps. They might feel very spongy while pumping because you have to pump past the spring tension, but in a pinch any presta pump should work.