bike problem - advice please

[jazzactivist]

Hi all bicycle riders. I have what might seem to be a laughable problem in that I can't seem to inflate my bike tyre. I remember doing this as a child with no problems. However, in trying to pump up my rear tyre I first had trouble fitting the nozzle of the pump onto the valve, and then have managed to deflate it rather than inflate it! Looking on the internet I see that there are two types of valve and mine seems to be a Presto valve as it is a road bike. Please can any of you provide some tricksy advice on how to get it right so that I can be out on my bike again before the weather breaks? Thanks X

[Clunkshift]

Jazz,

I imagine you are using a car tyre pump. If so you need an adaptor or a proper bicycle pump. see link:
http://www.matthewsbikes.com/techcorner/prestavalve.htm


If you buy a good stirrup type pump - they have double outlet heads which fit both types:

http://www.cyclexpress.co.uk/categories/Bike_Accessories/Bicycle_Pumps/Floor_Pumps.aspx


happy peddaling,
Clunk x.

[jazzactivist]

Thanks clunk. I do have a bicycle pump, two in fact, as I thought that the initial problem was the pump and went and bought another one! The problem seems to be that when I fit the bike pump nozzle onto the valve it lets air out instead of pumping it in. Is there a knack to fitting them together?

[Clunkshift]

I'm assuming that your Presta valve has the little collar on the top and that when you want to inflate the tyre you unscrew the collar first.

Then if you have a traditional telescopic plunger, you pull out a flexible adaptor tube from the handle end and screw it into the bottom of the pump, then screw the other end of the adaptor onto the valve.

If this is the case, try putting the flexible tube onto the valve first, then screw the pump onto the adaptor.


If you are all modern and have a pump which attaches directly to the valve, it has a housing, with a rubber sleeve inside the housing (and a locking lever if it is a posh one). Sometimes, the rubber sleeve is reversible and has a large bore end for Schrader valves and a smaller bore end for Presta valves and the rubber insert is retained by a knurled collar. So if the rubber is a very loose and sloppy fit (or fits on your car tyre valve) it needs to be turned round so that it is a tight fit on the valve body.

If you have a locking lever, this also depresses the end of the little bar sticking out of the valve. this will make the valve sound like it is leaking, until you pull the lever and lock it in position.


I can't help you with which way to turn the lever because they vary, so you have a 50/50 chance, but the pump should be a tight fit on the valve when it goes on and the locking lever is to stop the pressure blowing it off.

By now you can see why little brass adaptors are best sellers at cycle shops!

I recommend valve adaptors and floor pumps (2 handed stirrup type).