Valve Caps

[SnappyPix]

Does anyone know if leaving the valve caps on inner tubes increases the likelihood of damaged valves?

I seem to be experiencing a bout of flats caused by problems with the valves, rather than p*nctures.
I'm using long valve presta tubes, as my wheels are quite deepset. I'm really carefully when pumping up the tyre (ie making sure the valve isn't bent when unscrewed, etc and use a track pump to inflate).
The problems seem to occur when doing a lot of hill work/steep, windy bendy descents and have heard that leaving the caps on can cause damage to the valve as it pushes against the cap.
I make sure the tyres are aligned properly in the rim, that the inner tubes aren't pinched or the valve skewed, but have now had 4 flats in the past 6 months from the same problem.
Does anyone have any ideas? It's not the base of the valve that seems to be the problem, rather the whole thing fails. And I've tried 3 different types of tube!

[Grog]

Really I do not think there will be a big impact on flats, but I don't leave the caps on the valves anyways. They seem quite useless (unless you ride in the dirt I guess?)...

So nothing to loose!

[SadieKate]

What do you mean by the whole thing fails? Where is the damage? If you put the tube under water, where do you see the leak?

I only leave caps on my mtbike tubes. Never heard of them causing damage. It's mostly an image thing with roadies.

[annie]

I leave my caps on because they are yellow and they match my bike. Vanity.

I've never found any reason to believe they caused flats.............. whenever I have a flat, it's for a defined reason. The only time I've had problems with valves has been using a BAD excuse for a frame pump. Or a bad batch of tubes from the LBS, and they exchanged them gladly. I've actually never heard of valve caps causing flats........ maybe it's an urban myth.

annie

[SnappyPix]

The valves seem to fail at the top end, rather than at the base. Once they go, I can't pump them up at all, let alone put them in water to hunt for the hole!
Perhaps it's an urban myth about the valve cap - it was on a UK cycling forum, and I usually only take things that I read here as gospel!

[singletrackmind]

Valve caps are on millions of cars, atvs, motorcycles and bikes, to name a few. They don't intrude on the airtight part of the tube and if anything protect the valve from being depressed.
Look elsewhere for your flats, find out where the puncture is using water, as has been said, and match the hole with wherever it is on the tire or rim of your bike. If you are getting multiple flats in the same place find the problem and fix it, if the holes are in varied places in the tread area and you don't like flats get a liner.
Ok, just saw that last post.....could your source for tubes have a bad batch? I'm assuming you are able to pump up the new tubes with no problem so it's prolly not your pump? Sometimes there is also problems with pumps damaging the valves when they are tugged off but that is usually at the bottom of the valve.
Good luck with your flat eliminating!