3

I am switching from 700cx40 to 700cx32. I have a bunch of inner tubes that I bought for the old tires and are in the 40mm range, but I don't know anymore what the range is for each (I didn't keep the packages). Is there a way to tell? Or, if no, what can happen if I use a wider tube (say, a 35-xx or 37-xx tube on a 32mm tire)?

EDIT: OK, I see, the dimension is written on the tube. So, I have a 700 x35/43 tube. Is it safe to use it on 32?

  • Normally the size range of the tube is printed on the side of it. – Daniel R Hicks May 28 '15 at 11:02
  • It can fold on you . Give it light pump and put it in the tire to test. – paparazzo May 28 '15 at 11:04
2

Yes, it's perfectly safe to use the next larger size tube in a smaller tire. It's a common trick used by bike messengers to reduce the chance of flats. The only downside is a slightly heavier wheel since you're using more tube that you really need.

1

Probably fine - if you're really worried, buy new inner tubes and carry one of those bigger ones as your spare. Remember you're talking about 3 mm in size, in something made of rubber that

Even if its not race-perfect, will be good enough to get you home, or give away to a fellow cyclist.

Could also run them on a stationary trainer if you use one.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.