How can you tell, when buying Presta Road Tubes, if the valves are long or short?
Reason I ask is I got 2 flats yesterday and one of the tubes I used didnít have a long enough valve to get a C02 cartridge or pump onto it.
What do you recommend when buying tubes? My tire size is 700x23
1) Many tubes carry the presta valve length marked on the box. If they're not, you can literally just measure them;
2) The proper stem length is NOT a function of your tire size, but rather a function of your rim depth.
A 'standard' (is there such a thing with bikes?) Presta stem is about 35mm. For deep-section ("aero") rims, valves are available in lengths up to 60mm. Several intermediate lengths are available. You really need the one that fits your rim, leaving enough valve available for your pump to 'bite.'
There are also extenders....if you need long valves it's not a bad idea to get one of these and toss in the saddle bag. That way, if you are having a really bad day and ruin your back-up tube, and all your riding partner has is a short valve tube.....well, need I say more? Nothing worse than having a good tube in hand, and no way to pump it up.....