Presta valve...

[Catrin]

Last night I decided to check the air in my tires before my practice session today, more for practice than anything else. It turned out to be a rather lengthy process - and probably would have been hilarious to watch - as somehow I managed to let most of the air out of the tire... It was something like this:

1. Unscrew Presta Valve and connect floor pump to the valve (wheww, first step complete :)

2. Check gauge on valve - hmmmmm, no reading at all. Must be doing something wrong

3. Play with valve connector....hiss of escaping air.

4. Ok, pump a little, see what happens (the experimental method)

5. S*$&* the gauge isn't showing much pressure... what I am doing wrong?

6. While commenting to myself on the situation the gauge keeps dropping... time to start pumping!

7. pump pump pump pump pump pump pump pump

8. Man this is going slow! What is going on here? Pinched the tire and noted very little air was left in it.... Language immediately became...errrr... colorful!

I did manage to air the tire back up but it took a little time. From what I could tell, air was escaping the tire between pumps from the floor pump no matter how I had the valve connector set from the floor pump. Is this normal? I figure that I just need more practice - and I did manage to at least get the tire back up to 100 psi (the tire is rated for 100-120 psi).

Obviously I've never done this before - and I DO have a hands-on class scheduled at my LBS in mid-January to learn how to change an inner-tube\patch a tire\etc.

The tire seems ok this morning, hopefully there will be no surprises when I go out to practice this afternoon :o

Wheww... no problems with the tire (my very first tire-checking/airing). I haven't said that I am not exactly mechanically inclined...but I want to cycle so badly that I am working on learning the basics :)

[tzvia]

Air should not escape from the valve as you pump. The stem of the presta valve should go quite far into the chuck of the pump, I would say around 3/4 of an inch. Also, there is some resistance from the valve; I like to tap the end of the valve after unscrewing it to break the seal (a small puff of air will escape) before putting on the chuck. Usually the gauge will read the pressure after putting on the chuck, but not always, and I have to pump till pressure opens the valve and then I can get a reading and get it pumped up.

Yea it takes a bit to get used to presta, but once you do, you will never go back to schrader valves. It is so much more elegant and doesn't leak air like schrader can.

[Catrin]

Thanks for the tip. Someone suggested that either I didn't have the pump valve on all of the way, or that the floor pump valve wasn't closed properly. I figure practice makes perfect... I will keep your comments in mind this afternoon when I have another practice session. It's too cold to practice riding, so I can practice with my tires :)