Advertise on Bikeforums.net



User Tag List

Results 1 to 10 of 10
  1. #1
    Newbie
    Join Date
    Oct 2007
    Posts
    2
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    tubes for 700x34 cyclocross tires?

    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!

  2. #2
    Perineal Pressurized dobber's Avatar
    Join Date
    Oct 2003
    Location
    In Ebritated
    Posts
    6,556
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    This one has a range of 20mm http://aebike.com/page.cfm?PageID=30...ils&sku=TU9209 - Good tubes by the way, I run em on both my Cross-Checks.

    Them there inner tub things is stretchy. A 32 will work fine in a 34. And a 36 likewise. Now too big a tube will give ya some problems stuffing it all in there. And too small of a tube might stretch out a bit and be more prone to flatting. But in general if your within 2-3mm you'll be fine.

    Fact is, there is no guarantee that your 34 tire actually measures 34mm in some way.

    And I usually get what ever is on sale. They all come from China anyways.
    Last edited by dobber; 10-06-07 at 06:01 PM.
    This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.

  3. #3
    M_S
    M_S is offline
    All Mod Cons M_S's Avatar
    Join Date
    Dec 2006
    Location
    Face down in a snowbank
    My Bikes
    K2 Enemey Cyclocross franken build; Redline D660 29er, Volpe SS Cross
    Posts
    3,694
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I've gotten by using a 23 tube in my 28 road tires, and a 28 tube in my 35 'cross tires. If you pump up a tube quite a bit while it's outside of a tire, you wil see that it flexes a LOT, as the poster above said.

    As far as long valve stem...do you need it? I didn't think that the Poprad had wheels with a deep rim.

  4. #4
    Senior Member
    Join Date
    Mar 2006
    Posts
    944
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    It really does not matter too much. I have had students who had 26 inch tubes in their 28 (700c) wheels.

    Rubber stretches.

  5. #5
    Senior Member
    Join Date
    May 2007
    Posts
    152
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Using the 36 will give you a bit more rubber and puncture protection. A bit. not a lot, just a bit.

  6. #6
    Been Around Awhile I-Like-To-Bike's Avatar
    Join Date
    Oct 2004
    Location
    Burlington Iowa
    My Bikes
    Vaterland and Ragazzi
    Posts
    20,027
    Mentioned
    8 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by cprice404 View Post

    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!
    1) http://schwalbetires.com/bike_tires/tubes
    2) Yes. Marathon brand AV17 (Schraeder valve) or SV17 (Presta Valve) fit 28-40 mm tires. $5.85 each
    3) See 2)
    4) Yes. See 1) and 2)

  7. #7
    Newbie
    Join Date
    Oct 2007
    Posts
    2
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    sweet, thanks for all the advice.

    i don't think the poprad's stock wheels would actually require a long valve stem, but the tubes that it came with have one. they stick out quite a ways so i think i could get away with the regular ones.

  8. #8
    ♋ ☮♂ ☭ ☯ -=(8)=-'s Avatar
    Join Date
    Feb 2005
    Location
    40205 'ViLLeBiLLie
    My Bikes
    Sngl Spd's, 70's- 80's vintage, D-tube Folder
    Posts
    7,870
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Ive used a 23 in a 32

    No problems of the real, non-hypothetical variety, either
    -ADVOCACY-☜ Radical VC = Car people on bikes. Just say "NO"

  9. #9
    Seņor Miembro JustBrowsing's Avatar
    Join Date
    Mar 2007
    Location
    DC
    Posts
    603
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Tubes are stretchy. Hell, I've put a 20" BMX tube on a 26" wheel. Seriously, you should be fine with either the 32 or 36 tube. Or if you really want to make sure you're okay, get some of these Vittoria tubes rated for 28-47 tires.
    Hey! Get your mouse off my text!

  10. #10
    Senior Member sumguy's Avatar
    Join Date
    Aug 2007
    Location
    nw ohio
    My Bikes
    08 Novara Safari; 06 Schwinn Super Sport DBX
    Posts
    564
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Is tube size dependent on rim or tire size? Hybrid has 700x28/35 rims (according to the sticker) but 700x40 tires. Carry a 700x35-38 tube for emergency flat. Just curious.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •