Clincher tube size question

[Kingfisher]

25's are the largest i've run in over 40 years of cycling, so want to try out these in 28 for added comfort.

Just received a couple of the vittoria corsa g+ clinchers in 28 width.
Stupid question, but gotta ask....all my tubes say 700x18-25. I suppose it is necessary to get the larger 28 size tubes in order for this tire to fit properly?

[oldpotatoe]

25's are the largest i've run in over 40 years of cycling, so want to try out these in 28 for added comfort.

Just received a couple of the vittoria corsa g+ clinchers in 28 width.
Stupid question, but gotta ask....all my tubes say 700x18-25. I suppose it is necessary to get the larger 28 size tubes in order for this tire to fit properly?

No, 25 tubes will be fine. A wee bit thinner when inflated but no big deal. Inflate a tube outside of a tire and see it get hhhhuuuuugggge.

[palincss]

I use ultralight 18-25s on the bikes that have 25mm and 28mm tires. I use tubes marked 28-32mm on the bike that has 32mm tires. I've actually tried those tubes with 28mm and found them very difficult to install because the tubes are so large it's easy to accidentally catch a portion of the tube under the bead. The 18-25s are much easier to fit correctly.

[tumbler]

Will be perfectly fine for 28s.

[Brian Cdn]

On my gravel / cross bike, I've been running 18-25s tubes in 30mm cross tires.
No probs with mounting, pinches or flats.

[Cicli]

I carry a road tube in my 29er seat bag because its much smaller. I flatted about 10 miles out and threw in the tube. Road tube in a 29x2.4 tire. No biggie. Well I dont mountain bike much. A long time (year or so) later I was putting on some new tires and discovered the road tube still in there. It survived fine.

[thwart]

No, 25 tubes will be fine. A wee bit thinner when inflated but no big deal. Inflate a tube outside of a tire and see it get hhhhuuuuugggge.

Hey, we're trying to avoid political comments here...

;)

[carpediemracing]

My experience seems contrary to those above but I found that if I used undersized tubes they flatted pretty quickly. Not sure why but tubes are cheap enough that I tried with various set ups. With 18-25c in a 28c probably okay. I was trying 18-21c in a 23c and it didn't hold up, and I tried 1.25-1.5" tubes in 1.95/2.0/2.35/2.5" tires and they definitely didn't hold up. Even 1.75-2.0 tubes didn't work in the 2.35/2.5 tires (pre suspension). Pity because the tubes made a huge weight difference.

[Gsinill]

Hey, we're trying to avoid political comments here...

;)

He didn't say YUUUUGE!

[smontanaro]

Someone somewhere else (internet-BOB?) mentioned the Schwalbe tube finder, so I thought I'd pass the reference along:

https://www.schwalbetires.com/bike_tires/tubes/finder

In my experience, the part of the tube which is most problematic when trying to use it in a larger tire than the stamped size, is that transitional section between tube and valve. While you might be able to go to 28 with a cheap tube stamped "18-25," I wouldn't get carried away with it. Schwalbe's tubes are much more flexible in that region than most others I've encountered, so fit a wider range of tires, and probably tolerate use in a too-big tire a bit better.

[ColonelJLloyd]

Will be perfectly fine for 28s. +1 I always err on a smaller size if they don't match up well. Sometimes a larger tube than is necessary is like trying to stuff the sausage back in the casing. Very frustrating with snake bites, etc.

[icepick_trotsky]

A slightly too small tube is fine.

Do not try it the other way around. I've blown some tires off the rim.