I recently got new tyres 'Bridgestone Turanzas' and decided to check the pressure on them at my local Sainsbury's petrol station (UK). When I connected the nozzle of the tyre inflator machine air began to leak out the tyre. Previously I would stop this by pressing the nozzle in further at which point the leakage would stop. Unforunately on my new tyres the air continued to leak out at a rate faster than the tyre inflator machine could replace it. I then gave up, went home and used a bicycle pump instead which did the trick and confirmed the tyres are not faulty per se.

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However, it seems this schrader valve is not compatible with the nozzle on the air inflator commonly in use at petrol stations in the UK.

What can I do about this? Is there some kind of adaptor that would help solve this problem?

  • Have you tried the machine at another garage? May 24 at 16:51
  • This is most likely an operator error - even the comment from the OP says it is a schrader valve not Presta.
    – Solar Mike
    May 24 at 21:00

The petrol station air hose terminates in a fitting that fits onto a Schrader valve stem. The valve stems on your new tires are of the Presta type, more usually found in bicycles. The two types are dissimilar. Here's a pic:

enter image description here

The Presta valve stem is on the left, and the Schrader valve stem is on the right.

The two types are dissimilar, and don't directly connect. When you tried to fill your tires (with Presta stems) using the petrol station's hose (designed to fit on Schrader stems), it didn't work.

Most auto tires use Schrader stems; I've never before heard of Presta stems on a car. Still, adapters are commonly available in bicycle shops and online. They look like this, and are not expensive:

enter image description here

(both images taken from images.google.com)

  • Thanks for your reply. The tyres have schrader valves.
    – egg
    May 24 at 20:03
  • @egg if, as you say in your comment here that the tyres have schrader valves, why would you clearly state in the question that the tyres have Presta valves? Do you know the difference?
    – Solar Mike
    May 24 at 20:59
  • @SolarMike my mistake.
    – egg
    May 24 at 22:05
  • I've never seen a petrol station air hose that terminates in a Presta fitting; they're always Schrader. Thus, either a) the hose fitting was defective, b) the tire stem fitting was defective, or c) the user's manipulation of the hose was incorrect. May 25 at 15:18

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