Inner tube, your opinions please.

[Dag Hammar]

Eighteen months ago I fitted new tyres and tubes on my Raleigh bike. Marathon Plus tyres size 26 x 1.75. I also fitted new Schwalbe inner tubes, the AV12. At the time I felt that the new AV12 tubes did not seem to ‘fill out’ the tyre space prior to inflation but of course, once fully inflated they have been fine. At that time I wondered if I should have fitted Schwalbe AV13.

Now I am forced to fit new tyres and tubes on to my daughter’s bike. The tyre size is 26 x 1.5 ( 40 559 ), that’s the straightforward part.
But now I don’t know which is the most suitable inner tube for this application and I am conscious of the fact that this 26 x 1.5 is a slightly narrower tyre than I have on my bike. So I’m asking for opinions / advice for this 26 X 1.5. Schwalbe AV13 or the AV12 ?
I expect the reality may be that if I put an AV12 in the front and an AV13 on the rear, once inflated and in use I doubt there would be a noticeable difference but obviously I want to try and fit the best / most suitable one.
Thanks in advance and I look forward to hearing your thoughts.

 

[Pat "5mph"]

A quick Google shows an AV13 26" X 1.5/2.5 this range would cover both bikes.
I can also see an AV12 26" X 1.25/1.75 that would also cover both bikes.
I'm not quite sure what the difference is between the 12 and the 13, maybe valve length?

 

[annedonnelly]

I think it's just that there is a cross over in the ranges. If you needed 26 x 1.25 you'd use the AV12 and if you needed 26x2.0 you'd use AV13. But in the middle of the range you can use either.

I think I've a similar choice with tubes for my Marathon pluses and sometimes I've used the smaller ones and sometimes the larger and I've never noticed any difference.

 

[classic33]

You should be able to inflate either tube to around eight inches in diameter across the tube width, and around nine foot in overall diameter.
Without it giving, making the smaller increase you're bothered about seem nothing.

 

[a.twiddler]

The only advantage I can see is that if you have a stiff tyre, fitting a slightly narrower tube might be easier when it's new, with less chance of pinching it. Marathons are notorious for being hard to get the bead over the edge of some rims. Once the tube's been on and inflated, it would be hard to tell the difference next time you take it off as it will become more "baggy" compared with a new one. Even that is more noticeable with smaller diameter, narrower tyres such as on a Brompton, than larger ones.

 

[Dag Hammar]

Thank you to the four that replied to my question.
I have obtained one Schwalbe AV12 and when I get time at the weekend I will be fitting that. If it goes well I might get another AV12 or if it does not then I’ll think about perhaps buying an AV13.
Firstly though, if when I come to dismantle the front wheel if the tube in there looks in fine condition I will most likely re-use that because that front tyre and tube have never suffered a puncture.
I have just bought 2 x Marathon Plus tyres for the task so I expect to be swearing a bit and bruising my fingers and my palms at the weekend.