Sunday, March 2, 2008

The size of your tube doesn't matter that much. Really.

Once again, a reader has come to the authority and asked Cycledork.

Dear Cycledork,

We've had an exciting weekend of assorted flat tires and tube mishaps, so now is a good time to ask a question about tube sizing. The tires on my Giant OCR3 are 700 X 26C. On getting home from picking up a replacement tube (and CO2 canister) at my friendly neighbourhood bike shop today, I noticed that the box says 700 X 23/25C. Now they definitely heard me when I said "26" and they always know their stuff, so I'm assuming that this tube is the right size. But what's with the confusing numbers?

Curiously,

H. Trouser

Dear Mr. Trouser:

I'm sorry to hear about your flats and tube mishaps. The good news is your latest tube should fit your wheel and tire just fine. According to Giant, the OCR3 comes with 700x25 tires so a 700 x 23/25 tube should be fine, even in a 26 . Tirewise, the "700" refers to the diameter of the wheel in millimeters (it comes out to about 27 inches) and the "23/25" refer to width, also in millimeters (a hair less than an inch). Tubewise, the 2100, not terribly different than the OCR3, came with 25s. I've been using 23s for several years. You can probably go as skinny as 23 or as fat as 28 or so. No big deal. Ride and be well.

Yours in velophility,

Cycledork

2 comments:

Anonymous said...

Many thanks for the elucidation. As ever, your wisdom is much appreciated. I am proud to have changed my first road bike tube on the fly, in around 15 mins. Glad to hear that my new spare will work just fine.

Brian Rosson said...

Hi Cycledork,
I apologize for basically asking the same question but wanted to make sure I'm not throwing my money away. Similar situation as H. Trouser: I have 700 x 23 tires on my road bike and just bought new thorn resistant tubes. I realized that I purchased the 700 x 25-32c tubes. Can I still use them or would it be wiser to get the appropriate range?
Thanks for your help!
Brian