Originally Posted by Longfemur

I have to wonder how much some people who post on these forums actually cycle. Presta valves come on bikes that benefit from them. You don't need them on comfort bikes, hybrids or mountain bikes because the pressures aren't so high that you can't manage with automobile schraeder valves. You absolutely do need them on high pressure road bike tires. They are very simple to use. If you are having problems, you just haven't figured it out by yourself. Ask someone who knows to show you how.

Sometimes, on pumps with a head that locks onto the valve (the ones that have a little lever), the rubber in the pump head is compressed too much, making it difficult to remove it from the valve. If that's the case, try to untighten the plastic screwcap so that it's compressed a little less. Cheap tubes often have difficult valves. Get better tubes. Good technique also helps. Put two fingers under the pump head, one on each side (like a V with your fingers, around a spoke and under the valve). Put your other hand above just to catch your other hand as it comes up (to avoid any scrapes). Then just push up. If it doesn't come off fairly easily (with a bit of pressure), something is wrong.

Schraeders are for kids and people on bikes, Prestas are for cyclists. By the way, I very highly recommend using only Michelin tubes that don't have a thread on the valve body. These threads are useless since you neither need the cap on the valve or the valve nut. The smooth valve body is easier to deal with and it doesn't gradually chew up the rubber in the head of your pump.