One of my singles loses pressure faster - any clues?

Triathlon Forum
1

Hi there all,

First, confession: my training partner put me on to this site a while ago. I have now decided to end my lurking ways and show my face (at least in the cyber-sense!)

Second, praise: it is extraordinary to be exposed to a pool of knowledge with like-minded people on a forum like this. Awesome.

Finally, question (now that you’re all in a good mood!): I am running singles on my Zipp 440s and have noticed that the front tyre loses its pressure much more quickly than the rear (ie. ok when riding but a noticeable loss of pressure within 24/48 hours). The wheels are as new and my LBS re-glued the tyres for me a couple of weeks ago. Not a slow puncture as far as I can tell.

I have experienced this kind of problem in the past with clinchers (partially torn tube valve etc) but this is my first foray into the glued-on world so I am wondering what’s going on/whether this means anything?

Thanks in advance for any thoughts!

Matt

PS Tom D - my training partner and I often talk (at least half seriously) about coming out from behind the corporate veil and getting real jobs. If you are ever considering an Australian franchise and need a couple of bodies let me know!

2

Your problem is probably in hookng up the valve to the valve extender. When your LBS glued the tire on, they twisted the valve in the open position. Tires just don’t hold air very well that way.

There are valve extenders that replace the existing valve and move it beyond the rim where you can get at it, but I don’t know of one that is long enough for a 60 mm rim wheel.

My 404 deflates slowly, then it seems to get to a certain low pressure and completely deflates. I don’t like this, but it has never been a practical problem.

3

thanks Art,

Yeah I think I may have moved the extender a bit when pumping up the tyre (I need to be careful with the track pump - once I nearly cut my finger off on a bladed spoke trying to get the pump valve off the extender!)

Not a practical problem at this stage as it stays inflated for 48 hours or so - hopefully long enough for me to finish the 1/2 IM bike course I am doing this weekend!

Cheers