Sorry if it’s a dumb question

Can I use a 27.5x2.125 tube in my 27.5x3 tire in a pinch? I don’t do any crazy stuff just light trails and if I can do I put in the same amount of air? I only want to use this if I happen to get a flat…

In my experience, yes, it will work. Tube quality varies a lot, so buy a good one. (I’ve been running a 2.125 tube in my 3" tire for several years with no issues.) I use the same pressure as always. (Although this is kind of low, since this tire is ridden exclusively off road. Between 15 and 16 psi, typically.)
My opinion/experience only. As always, “your mileage may vary.”
Good luck! :slight_smile:

Tubes are pretty flexible when it comes to sizing. You should be fine but it wouldn’t hurt to get the correct size.

Not a dumb question at all, but not a great subject line for the future. The question itself would have been better.

3" tubes can be heavy, especially if they’re made to be puncture resistant. So I bet a lot of people use skinnier tubes and carry patch kits. :slight_smile:

People stretch 29" tubes onto 36" wheels. Tubes are stretchy.