Hi, apologies if it may seem that this thread would be more at home in the "Cyclocross" Forum... but I use my cross bike for commuting and am not much of a racer, so after much deliberation I decided to post here.
I recently bought my first "real" bike. I've been using an old 40+ lb tank of a MTB for commuting for the last 5 years or so, and after borrowing a road bike from a buddy for a few days I finally decided to treat myself to a new bike a bit more suited to my riding conditions. I settled on an '07 Lemond Poprad (mostly for the steel frame + disc brake options) and I absolutely love it.
BUT... I'm getting ready for a 100k ride that is coming up in a few weeks, which will be about twice as far as I've ever ridden in one ride before--so I want to make sure I'm prepared. Amongst other preparations I decided now would be a good time to pick up a few spare tubes.
I've never had ANY problem finding tubes for any bike I've owned in the past so I didn't pay a lick of attention to the availability of tubes for the tires on my new Poprad when I made my decision to buy it. Now that I've started looking for them I'm realizing that they are an unusual size and I don't know where to find tubes. The tires are 700x34 and the stock tubes have a long-stem presta valve. I've checked 3 local bike shops and it seems like all of the major brands of presta tubes that they stock are 700x28-32 or 700x36+. There seems to be a gap between 32 and 36, which, unfortunately, is where my tire falls. I've also spent a bit of time poking around the web looking for online bike shops, and the tubes I've found on those sites seem to be sized in the same way (i.e. nothing available that says it'd fit a 34).
Now, the guys at 1 LBS tried to sell me a 32 tube and said it'd be fine, and the guys at another LBS tried to sell me a 35 and said it would be fine. Maybe either would be fine but I'd feel much better if I'd gotten a consistent recommendation, or if I could just fine some that claimed to fit a 34. It seems like there are a fair number of cyclocross tires out there that are 700x34 so it doesn't seem like this ought to be that hard.
So... long rambling preamble having been completed, here are some questions that I have, the answers to any of which I would be tremendously grateful for:
1) Does anyone know where I can find a tube that is actually rated for a range that includes 700x34?
2) Regardless of #1, Is it OK to use a 700x??-32 or 700x36-?? tube on a 700x34 tire?
3) If so, is there a reason why going with the undersized would be wiser than the oversized, or vice-versa?
4) While I'm seeking tube advice--does anyone have any affinity for a particular brand or style of tube? I'm probably looking for something in the "intermediate" range between minimum weight and maximum durability. I'm commuting and not racing so obviously avoiding flats is the most important concern, but I'm also still relishing the performance difference between my new bike and my old MTB so I don't want to go over the top on tube durability.
Greatly appreciate any insight anyone can share... and if I ought to have posted this to the cyclocross forum instead, please let me know!