6

My hybrid bike tire measurement says 700x35c. I ordered a replacement inner tube stating it was 700x35-40c but when it arrived it is actually 700x38-45c. Could I still use this or will it cause a problem, e.g. with my brakes?

PeteH
  • 9,733
  • 5
  • 33
  • 53
Cesky
  • 61
  • 1
  • 1
  • 3
  • 4
    Any larger and I would worry, but that much of a mismatch isn't likely to be a problem. I would be suspicious of your supplier, though, if they can't supply the right sized tube. – Daniel R Hicks Nov 05 '15 at 12:05
  • 4
  • 2
    You're only slightly over the speced size but to be extra cautious you might dust the tube with cornstarch to keep it from sticky-binding to the tire, and after installed pump it up about 3/4 the way up, then deflate it, then pump it up to full desired pressure - you want to work out any kinks and folds from the tube. – obelia Nov 07 '15 at 18:02

1 Answers1

9

It won't cause a problem with your brakes – the tire casing will prevent the tube from "over expanding."

Your tire is a bit smaller than the small end of the range for the tube. You may find it a little harder to fit in the extra material and it would be good to take a bit of extra care to make sure you don't pinch the tube if you use tire levers.

Be careful to avoid any twists, but it should work. This question, Using a wider inner tube, explains in more detail what can go wrong if the tube is significantly too large, and also points out that inflating the tube slightly will ease installation – especially in a case like this.

dlu
  • 7,046
  • 2
  • 23
  • 50