Inner tubes.. Am I going mad?

[crE]

 

[crE]

Well. I fitted it anyway. And it worked fine

 

[stevew]

looks like it maybe a 700c tube in a 26" box

700c = 622mm bead seat diameter
26" = 559mm bead seat diameter

 

[crE]

Ahhh. I took it for a test ride and it works fine. No bumpiness or anything. Any problems if it is actually the wrong tube? The one that was in there originally looked the same size when compared

 

[stevew]

Bit hard to be sure. When inflated outside the tyre it will appear big, that's normal. The top picture you show, when its just out of the box, looks slightly suspect but some times they do look a little like that and then with a minimum amount of air in (just enough to give it shape) it fits OK. Did it go in without overlapping on it self? If so that should be OK. Often there is some writing on the tube it self saying what size it is.
As the original one looked the same i would guess it's all OK.