Have you ever got up in morning and found your tire lacking air? If you use Schwalbe presta valve tubes check the removal core. It just may need a little tightening. I have a small but useful tool that was given to me many years ago by Dana at Bent Up Cycles. I use it to tighten loose Schwalbe valve cores without having to use pliers that may damage the threads upon which the valve cover screws onto.
|A Schwalbe presta valve core removed from the valve and the hard rubber valve core tightener.|
The tool is small. I keep a red string tied to it so I can easily find it without having to reach for my glasses which always seem to be where their not suppose to be.
The valve core tool is available at Amazon.