Tube size issue?
 

Recently went from a 700x23 to a 28 tire (Gatorskins). Rides great. Went to check on the box from the set of tubes I've been using and they are Michellin Airstop butyl 700c 18-23cm. Is this dangerous? Should I buy replacements?

Thanks

No. Not dangerous. If you have ever pumped up a tube outside of a tire to check for a leak you can see that tubes will expand a lot without any damage. What might happen is that you will have to top off the tire pressure in the tire slightly more often but not enough to be a concern.

I ended up replacing them with 28-32s. Noticeably thicker rubber. Little heavier. May go back but I was curious and wanted to give my LBS some business.

https://www.giant-bicycles.com/nz/70...-48mm-threaded

Your running gatorskins and you are worried about a heavier tube?

I found the tubes made for 28 tires were needing topping off as much as the originals. I went back to the originals to save weight and I prefer Michellin Airstop tubes, even though I'm using Gatorskins :)