CO2 Inflator Questions
 

Santa brought me a Ultraflate Plus - 16 oz CO2 inflator for Christmas. Of course I couldn't resist installing the cylinder and playing with my new toy.

Here's my question. Now that this seal has been punctured will the device hole pressure or will it slowly leak out over time?

Or, would I be better off putting the inflator and a virgin cylinder in to my bike pouch and only install the cylindar when I need to inflate a tire?

Thanks in advance for your replies.

I have no idea how long a punctured cylinder will hold pressure in the inflator, but I wouldn't bet on tomorrow. I don't think there's any point in carrying anything but virgin, unpunctured cylinders with you.

What kind of bike? 16 oz. is enough to inflate a road bike to roughly full operating pressure. The CO2 leaks out much more rapidly than air, however, so you'll have to top off your tire the next morning. When you're fixing a flat on the road, after you install your new inner tube, carefully check both beads all the way around to be sure the tube isn't caught under the tire bead. Once you start inflation using the CO2 it only takes a second or two to inflate the tire so if you've pinched a tube there's no stopping to adjust the tire and start over.

I "pre punctured" a cartridge once. They do leak, although its pretty slow.

There's definitely an art to using CO2 cartridges, and it's worth spending a few bucks and learn how to use them in your nice warm home. Like RG said, it's easy to pinch-flat, so to speak, unless you're very careful.

Yes, it's a good idea to practice and it's a good idea to have more than one cartridge with you on the road. Nothing more miserable than being in the middle of nowhere having already spent your only cartridge:cry:

How long the pressure will hold depends on the quality of the inflator, but yes that cylinder is toast. You should carry two new cylinders and only puncture them when they are needed.

They'll go flat pretty fast once you puncture them.

I buy them in bulk on the internet. Lots cheaper than bike shops and it's the same CO2. ;)

J.

JohnJ80, do you get them from Planet Bike?

Nope - not planet bike, why?

Actually I was asking JohnJ where he got his in bulk. but I am looking for sources. Going to get a Giant Defy 1 soon...probably wait until after my hand surgery and recovery, but I'll want some in case of flats...easier than pumping a tire up from zero.

Free shipping

http://www.redrockminnesota.com/serv...hreaded/Detail

No. I just google it and look for the cheapest. Here's another example:

http://www.gas-depot.com/products.ht...=0&sort=normal

item $15.90
Ship $ 9.54
Total $25.44

I get them from Redrock also, but through Amazon; just over $1 each. Having a good inflator will prevent having a CO2 failure destroy a ride. I highly recommend this one: Portland Design Works Shiny Object CO2 Inflator. Having a knob, instead of a press to fill, lets you control inflation, so you can inflate the tube slightly to avoid tube pinches, just as you would if using a pump.

How is a knob to twist any better than a trigger?

Don't know that it is, as I haven't used one with a trigger, although clearly the knob allows you to let go, as it fills at a controlled rate, thereby not freezing your fingers (plus the one I mentioned has a leather tube to slip over the CO2 canister to protect your hand from the cold). I was comparing the knob design to those where you press the inflator over the valve stem to release the CO2. I found that approach more prone to failure, especially if you neglect to open the valve (Doh!) It's either open or closed, and by the time you realize the valve is closed, the canister 'ist kaput'. If you have merely cracked open the knob, and realize you didn't open the valve, that's a 'recoverable incident'. Of course, due to my feeble mind, I now always remove the valve stem cover and open the valve before I store a tube in my saddle bag. That way it's ready to go, saving time and preventing any chance of my trying to inflate the tire with the valve closed.

Easier to control. For instance, you can easily just dribble the gas into the tube. I also feel that if you have to nurse a tube home - say a leak that your sealant didn't' get, you can seal it up better to keep the remaining gas in the cartridge long enough to get home.

Also, most of the knob ones (Planet Bike, Portland Design, and my favorite - Silca) tend to be the smallest and lightest. Small is good.

J.

There are several different CO-2 inflators and some seem to have better O rings than others. Some also have triggers that allow slower inflation. I have a friend that has one that seems to hold C0-2 for at least one or two days. I have an Air Chuck ands once puncture the C0-2 it is pretty much done.

In an unrelated story I have had a CO-2 that was still intact and once punctured it turned out to be empty. :eek: I had another cartrage but thank goodness I had a pump as well.

I have a bunch of cartridges, so many I have given them away on rides. There is a baggie full on the table for our daughter who started riding this last year. And I still have more than I can ever use. I own a fire equipment company. Two of the brands of fire suppression systems use 12 and 16 gram cartridges, which are replaced every 6 months. I am not comfortable tossing the pressurized cartrideges in the trash or recycle bin. And no, I will not send you some. I don't ship haz mat. But, if you are a customer of a suppression system company, they may give you some.

I am not a fan of CO2 carts. Yes, they are faster than pumping the tire by hand, but you have to execute perfectly, and they don't hold pressure. I think someone explained that CO2 leaks more readily from innertubes (smaller molecules than Oxygen?), but I figure that if the CO2 required to make your tire the size it's supposed to be under pressure is compressible enough to fit into that tiny cylinder, then it's not going to resist the pressure of your body weight as well as if you filled the tube with real air. In other words, why don't they fill those tiny cartridges with air instead of with CO2? Because it won't fit. But because CO2 is compressible enough to fit, then by that nature it will not hold your tire shape very well.

I still carry a full-size frame pump. Free air, and it keeps you warm on cold days.

L.

It's not the space, it's the form, your tire holds gas, a cartridge holds liquid CO2 which is at very high pressure, when you use the cartridge the CO2 turns from liquid to gas as the pressure is reduced to the point where it becomes gasious, but it doesn't all turn to gas at the same point, as long as there is some liquid in the cartridge, it will hold pressure, and inflate your tire. This is why CO2 is used rather then air, which will not compress into a liquid.

Why CO2 leaks out of a tire faster then air, that's a good question, as long as it stays in long enough to get your ride completed, it doesn't really matter.

+1

IIRC, the "leak" issue has to do with the relative partial pressures of each gas on each side of the Butyl barrier. Air is the same gas mix inside and out while CO2 is not. But I don't always IIRC well. ;-) I always just let most of the CO2 out when I get home, and pump it back up with air. Tires lose CO2 about twice as fast as they lose air, which isn't very fast. And, by the way, pressure is pressure. The CO2 holds you up just the same as the air does. And if you want to lose air fast, go with latex tubes!

I found an inexpensive but very well made CO2 inflation head and bulk cartridges at Amazon last year. I always have an un-punctured cartridge threaded on but not broken and 2 spares in my under-seat bag along with a spare folding tire and tube. I hate to push or carry a bicycle something fierce.

Bill

I do the same. My inflator is designed with a hole in the bottom of the container part, so you can insert a cartridge upside down and still screw the top on fully. The nipple on the cartridge sticks out the hole in the bottom. When I need to use it, I unscrew it, turn the cartridge around and rescrew it. That lets me carry one more cartridge than I would have been able to otherwise for the same amount of space taken in my bag.

Resurrecting an old thread.

Today on a ride, my CO2 inflator would only manage to inflate my tire to (my guess) 60 psi. First my tire was a little soft, so I tried cartridge 1 to no avail. Later, decided to replace tube preemptively at a rest stop, same thing with cartridge 2. Later on, I had an actual flat, and cartridge 3 no better. I can't imagine my inflator being bad, only used it maybe 20 times. Cartridges seemed fine, had CO2 left in them. Just couldn't get my tires hard.:eek:

Bad inflator?

I had some bad experiences with CO2 inflators last year. Perhaps I was holding the inflator in the wrong position (not vertical), but the cold CO2 froze the inner tube during inflation, which then cracked. I got myself a good hand pump. But I think a better inflator with the ability to control the flow rate better, and improved operator technique, might be called for.