Which tubes

Alibran

Stupid question, but I've been looking on Wiggle and can't figure out which inner tubes to buy. I used to just go into my local bike shop (who sold me the bike) say I needed a couple more tubes, and they'd sell me the right ones, but that isn't an option now.

I'm using the standard wheels that came with the bike, 25c tyres, and I was going to buy a multipack of 5 or 10 tubes, like the Conti or Vittoria ones, but there seem to be so many options to choose from. How do I know which ones I need?

Erudin

Expect these will do: Continental Presta 42mm 700x18-25 Race 28

Presta 42mm is the type and length of the valve
700 = for 700c wheel size
18-25 = fits 18 to 25c tyres

Mad Roadie

Alibran
check out Absolute cycles - they are bundling 5 packs of Conti tubes for much less than Wiggle

crankycrank

OK, here are the basics to tube buying.
1. You need to know air valve/stem type. Presta or shrader.
2. Air valve length. Just measure what you have now and buy something within a few milimeters of the same length. Box section non-aero rims usually take around a 36mm length stem.
3. Tyre circumference and tyre width. Yours are 700x25c so 20-25mm, 25-28mm, etc tubes will work. If you aren't planning on switching to a wider tyre get the smaller 23-25 size as it will be slightly easier to mount the tyre without pinching the tube and also a few grams lighter :roll:.
4. Tube durablility. You can get superlight, thin walled "racing" tubes at around 65 grams which are more supple and lively but puncture easier or go with the super heavy duty types (emphasis on heavy) which of course will resist punctures a little better but feel less lively. Most manufacturers make 3-5 different weights of tubes which is usually listed on the box in grams. (note: Most of your puncture protection comes from the tyre.)
I'm not even going to get into "what's the best brand" as I've had good luck with most of them and everyone has a favourite.