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I have a road bike here with 622-16 wheels and Schrader valves. As I needed to replace a tube, I found that most options in the 622-23 size use Presta valves. I read around a bit and found people suggesting rim hole reducers as in Can I use a Presta tube in a Schrader rim? among other places.

This didn't sound too hard, so I went ahead and ordered Presta tubes along with these Mavic reducers.

Mavic valve hole reducers

Now that I have all parts in front of me, things are not as foolproof as I thought they would be. For one, the reducers are not symmetrical and can be inserted into the rim from either side. However, neither side feels like the clear choice. Rather, relying on the fixing nut of the valve alone seems not to be bad. Let me illustrate.

Hole reducer from the outside: enter image description here enter image description here

From the outside the reducer fits snugly, but on the inside it creates a bulge that the tube needs to wrap around.

From the inside, the hole reducer doesn't really fit, however. I might not be pressing it in hard enough, but in this way the valve does not get through. enter image description here

Finally, I could just forgo the hole reducer. The valve comes with a nut that fits the drilled hole snugly. Is this sufficient to prevent the tube hernia mentioned in Can I use a Presta tube in a Schrader rim? ? enter image description here

What's my best option here? Do I have to get another set of grommets or should I just stick to Schrader valves in this rim even though the choices are few?

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2 Answers 2

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With the Mavic adapters, the lip is supposed to go on the outside. They're not intended for use with single wall rims, hence the problem you're having.

On a single wall rim like yours with the relatively deep, narrow channel in the rim well between the reinforcing sections, none of the reducer grommets available are going to work very well. The other option are the aluminum ones, which are usually superior, but they install on the inside and here they wouldn't work.

Those Presta nuts that sink into a Schrader hole are bad news. They do nothing to prevent the core problem of Presta tubes in Schrader holes, which is stress around the valve from not being supported by the rim eventually causing the tube to rupture. Maybe on a single wall rim this is less of an issue, but I still don't like it.

Just use Schrader tubes. 700x23-25 / 27x1 SV tubes are perfectly common.

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  • Thanks for your input. I was afraid of something like that, but it makes perfect sense. Sidenote: SV tubes seem to refer to Sclaverand (=Presta tubes) over here (Germany). For AV (Autoventil = Schrader), I only see few options. Actually, I only see the Schwalbe AV 15 right now. I'll see what I can find.
    – Matthias Kauer
    Sep 18, 2016 at 8:45
  • I went over Conti, Maxxis, and Michelin now to find that their relevant tubes only come with Presta. There is a Kenda 700x23/25c (which is the one I had previously), but I cannot find it in Germany. I suppose the Schwalbe AV 15 is really my best choice. Fingers crossed that they remain available.
    – Matthias Kauer
    Sep 18, 2016 at 9:44
  • That one should be fine, but for what it's worth, usually a tube like this (not one of the most mainstream permutations) is going to just be a generic/house-branded item, or branded Kenda/CST/IRC (one of the rubber giants that make all the tubes). That's what I'm used to in the US at least. Schwalbe is an exception as a tire company with a full tube line.
    – Nathan Knutson
    Sep 18, 2016 at 15:28
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I don't use Presta tubes so I'm guessing in the dark.can't you adapt the adapters,,cut and file them to fit?.even as a tempory fix.apologies if I'm not reading it write.

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