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Discussion Starter · #1 ·
I am looking to build a short hose for the purpose of using one tubeless tire well seated to a rim as an air chamber to seat another tubeless tire.

I do a lot of solo rides far from help that would leave me with quite a hike out if I couldn't seat a tubeless tire. I have carried a pump and a couple of C02 cartridges, as well as a tube. In the few instances that I had to throw a tube in, it wasn't a great experience. In one cause, I actually couldn't get the removable stem out because of how tight it was (didn't have a wrench/plier and removing by hand was impossible).

I'd like to make a hose with double ends intended to clamp on either schrader or presta so that I can stop carrying C02 cartridges and possibly stop carrying a tube.

For home use, I was thinking of getting one of the common "boost" reservoir bike pumps, but if this works well, I could see myself just inflating one tire to max pressure and using the hose to rapidly seat the other.

The technical limitation I see is the way the presta valve is intended to work. It doesn't really want to give up it's air in a hurry. I could see adding a presta to schrader adapter and then the air head would push the valve on the "donor" tire so that air could flow to the other tire.

Has anyone made anything like this? Am I crazy? :) It seems like a commercial product like this would have a place, especially considering all the boost reservoir pumps sold when most people trying to seat a tire and a perfectly functional air reservoir just a few feet away (the other tire).
 

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Yes. You are crazy. That aside, a way it might work is with a Y setup where two arms of the Y would connected to the stems of the tires with presta cores removed. The third arm would be connected to a pump. There'd be a valve in the arm leading to the tire to be seated. Close that valve and pump the good tire up to the max tire/rim pressure. Open the valve to let the air blast, such as it may, into the tire to be seated. This would be pretty easy to construct with a couple of thread-on presta chucks, some tubing, a y fitting, ball valve, old stem (to attach the pump), hose clamps where needed, and a little ingenuity.
 

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Neat idea, but it sounds like a pain:
  1. Fix leak in tire
  2. Inflate other tire to maximum pressure
  3. Join tires with hose
  4. Hopefully seat the tire
  5. Reinflate both tires
Your arms are going to be really tired.

Yeah, dealing with a tube isn't much fun either, especially with sealant squishing out the sides, but it would be a lot quicker and a third less pumping.

If it's just a matter of removing the valve, look into the Problem Solvers Super P-Nuts or Big P-Nuts.
 

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I don't see how it could possibly work, not enough air volume. The full tire would only empty half of it's air into the flat one. Co2 cartridges are pretty small, I'm a minimalist ww and even for me carrying a couple of them is no big deal.


A tube will always fix your flat so I'd recommend always carrying one as a failsafe. Screw valve stems on hand tight. Maybe practice changing a few flats at home until you're comfortable with it.

Plug kits and extra sealant are great to have too but as you know may not always work.
 

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Discussion Starter · #5 ·
Thanks for all the replies. I will check out the "Big P-Nuts" from Problem Solvers, especially because 2 wheelsets I ride on currently have Presta. On the day when I couldn't remove the stem, it was actually an aluminum schrader valve from 949 racing I had seen others recommend on this site. Well built little valve, but it is rough to remove without a wrench. I could look for another wingnut type option so I don't have to carry a wrench.

I see your point JB Weld about the volume, but I am surprised that people are selling little 1L canisters for the same use. Even if you fill them up to 160psi, you still have almost as much air to work with inside a typical trail tire at 40psi (usually well over 6L total volume, assume the tire is willing to give up 1/2 its air).

As much as I'd love to have a small light kit ready for most situations, I have gone through 2 CO2 cartidges needing a third. Sometimes you think you have a tire repair sorted out and it still won't seat (bent and gouged rim). I have gone to a tube only to get a flat (some places are so full of thorns you avoid tubes at all costs). I have stitched a tire sidewall trailside.

Sometimes I wish there was a schrader valve on the frame and I could just take it to 160psi, then use it to seat a tire.
 

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Someone should make a section of the bike frame into an air tank so you could fill up on the trail. Just fill it before a ride and have on-board air. I'm guessing it would have to have a over-pressure relief valve so it wouldn't be a grenade.
 

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Someone should make a section of the bike frame into an air tank so you could fill up on the trail. Just fill it before a ride and have on-board air. I'm guessing it would have to have a over-pressure relief valve so it wouldn't be a grenade.
...or maybe someone should make some sort of vessel that could hold a large enough quantity of pressurized air to inflate a tire and yet be small enough to easily fit in a pocket or small bag :p

jk, it does seem a simpler solution though.

I don't like the environmentally unfriendliness or expense of them but as seldom as I get flats and as well as they work it seems like an acceptable compromise. Mini pumps are great too but they take about 50x as long as co2, plus you're unlikely to seat a tubeless tire with them. I've yet to get a flat that unseated my tubeless tire though.
 

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I don't see how it could possibly work, not enough air volume. The full tire would only empty half of it's air into the flat one. ...
That is why I suggested, if trying this, to inflate the full tire to max rated pressure first. Gotta check the tire and rim spec, but the 2.4 tires I have are rated at 50 psi max. And, the idea is just to get the tire to catch air, not necessarily get the bead seated and both up to operating pressure, which can be done after the the tire is catching air.
 
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