The Inner Tube Thread

[davitron]

I was surprised I couldn't find a dedicated thread to inner tubes so here it is!

Almost all resellers I found sell inner tubes without mentioning their brand nor the angle of their valves, so unless these resellers are dedicated to EUCs, their inner tubes may not fit. Better ask them, but first we need to know what to ask!

I found that the information about inner tubes is segregated in different threads, but I couldn't find any dedicated discussion regarding the different materials used in inner tubes nor information about the valve angle nor even the most recommended brands (there are inner tubes from CST, Kenda...).

Hopefully someone savvy shares that information here

For now here there are some pictures that show the difference between the valve angles:
 

Edited August 10, 2020 by davitron
Fix images

[davitron]

From what I found in this forum, the inner tube's valve that is compatible with all EUCs is the one bent 0º, but does anybody know if the ones bent 45º fit as well?

I see a 45º valve here that didn't work:

but cannot find if it didn't work due to the 45º valve angle or something else related to the tire mod...

[mrelwood]

18-inchers usually have enough room for valves bent in any way, but the smaller ones are picky.

 There are some codes for different valve styles (TR87, PV78, etc) that in my understanding tell the height, length, and amount of bend, but this code isn’t usually mentioned. Just that it’s a bent or a straight valve.

45• bent valve can mean two things. That the valve stem has been bent to a 45• angle, then installed in the tube, pointing anywhere from 0• to 90• from forward. Or, a bent valve (30•, 45•, 60• or 90•) is installed to point 45• to the side.

I have not been able to determine a reliable method of getting the kind of valve one would need. Maybe looking for a tube specified for the exact wheel would work, but it would of course limit the sources to just a few EUC sellers.

[davitron]

I've been researching a bit more about inner tubes regarding the recommended size depending on the tire size, but I am bit confused as it seems some people (and sellers) have inner tubes narrower than the tire. For example using a 16x1.75 inner tube with a 16x2.125 tire (instead of also using a 16x2.125 inner tube), or a 16x2.125 inner tube with a 16x2.5 tire.

@mrelwood or anybody else, is there any advantage or disadvantage in using inner tubes narrower than the tire?

I'm asking because I noticed some damage in both of my inner tube's sides apparently due to rim/tire-edge rubbing and I'm wondering if this is happening because the inner tube is the same size than the tire (16x2.125).

[mrelwood]

Some inner tubes have a range of sizes it is designed to fit. For example 1.95" - 2.125". I do not recommend using tubes of different size than the outer tire. The tube will always fill up the cavity it's in, so a smaller tube will have to stretch out thinner than what it's designed for. I don't like the idea of a thinned out inner tube on an EUC. The tubes are often of a lower quality anyway, as you have now found out yourself.

[davitron]

Then any idea for the reason of such damage? I'm not home now so I cannot share a picture but (trying to explain it with words) basically my old inner tube has on both sides like a "line" of wear apparently due to rubbing with either the rim edges or the tire edges. If I'm not explaining myself properly, imagine a drawing of an inner tube on its side (simplifying: two circles), the wear I am talking about looks like another circle in between the two circles (the inner tube). Maybe this explanation is more confusing... sorry I'll take a picture when I return home

[mrelwood]

I think I got the idea. Cheap inner tube and possibly a bit low tire pressure would do that to a tube in a few thousand miles. It’s a wearing part after all, I would just replace with a new one of the correct size.