Portable air, NOT a compressor

I have a Slime compressor and I've used it many times. My problem is the time it takes to pump up a tire. It seems every time I have a flat I need to fix it and get moving. The compressor takes way too long. Also it doesn't work for getting the tire to seal on the bead once it's been broken. I'd like to rig a portable CO2 or air tank about the size of a MSR fuel bottle and mount it to the bike. I've used the small CO2 bottles on the dirt bike and they just don't seem to hold enough air for street bikes but work fine for tubed tires on the dirt bike.

Will a bottle like an MSR bottle or paintball bottle work? Will it hold enough air? Will I need CO2 or can I just fill it with air? Can I convert a paintball bottle with just a regulator and a Schrader valve?

The volume and pressure required are questions I don't know how to ask let alone answer. It sure would be nice to have a readily available air supply that I could easily refill.

The small, 16 gram, CO2 cylinder on my racing bicycle inflates that tire up to about 60 pounds (tire needs 100 pounds), it has a very small volume. I can't see it providing enough ummph to bead a tire. Perhaps there are other canisters, as you suggest, paint ball that could do what you want. I believe they are filled with compressed air though, not CO2. The pressure they seem to be able to take (if you could fill it) are certainly high-into the thousands of lbs per square inch. Controlling the flow might be the problem.

I looked up some small air tanks, sized for air horn or air ride suspensions. They are one half to one gallon in size and capable of holding 150-200 lbs pressure. My guess is this might do it, but you give up storage space to carry it.

For a real "red neck" way to do it I have seen a number of videos showing people achieving a tire beading using ether and spraying the inside of the tire then igniting. I might try this off the bike, maybe, in a pinch. On the bike I don't think I'd do it...but...

Have fun. No doubt some better answers will come up.

playinatwork said:

I'd like to rig a portable CO2 or air tank about the size of a MSR fuel bottle and mount it to the bike.

The volume and pressure required are questions I don't know how to ask let alone answer.

Click to expand...

I can help you with some of the math and practical considerations.

Not sure of the exact volume of a motorcycle tire, but let's say a rear tire is in the ballpark of 10 liters. To inflate it to 40 psi, the absolute pressure inside the tire is 55 psi, and that's what matters. So you need 10 liters times 55 psi. That means if you have a 1 liter container, it would have to be at 550 psi. But its not quite that simple, depending on how much 'reserve' pressure you have. For example, if you had the 1 liter/550 psi bottle available, and equalized it into the tire, you'd now have 11 liters of volume (10 for the tire, 1 for the bottle). So you'd have an internal absolute pressure of 50psi (11 liters * 50 psi = 550) or a gauge pressure of 35psi.

The working pressure of CO2 is around 1000 psi, so it would give you some extra margin and reserve pressure.

With a CO2 tank you have to go to an industrial gas place to fill it with liquid CO2, and you have your 1000psi from the natural working pressure of the CO2. Finding an air compressor that can achieve 1000psi or higher with plain air is also possible, at either a dive shop (3000psi) or maybe the same place that could fill a CO2 tank with liquid CO2. Bottom line is you aren't going to fill it yourself with either air or CO2.

The next hurdle is to convert the high pressure tank valve over to a schrader valve to attach to the tire. Depending on which style tank you go with, this will range from very easy to practically impossible.

The easy path is to buy a small standard CO2 tank, with a shutoff valve and pressure regulator to step down from the working pressure to normal tire pressure. Then you can attach any type of hose to the low pressure outlet side, and adjust the output pressure setting via the regulator. The problem with that is between the tank, the valve, and the regulator, its probably a bit larger in size than I suspect you'd like, and it probably costs close to $200. I'm not familiar with all the possible sizes, but for pure practicality that's probably the best approach if you can find something in a size you can live with. It will be safe, reliable, and you won't have to rig anything to make it work, it will just work.

A more difficult approach would be to try to adapt a paintball CO2 tank. I think there are more small tank sizes available for paintball applications, but I'm not familiar with any of the hardware/fittings for those, and you may run into proprietary designs. The best case scenario would be if you could find a paintball tank that is compatible with a standard valve/regulator assembly, but I suspect that's not likely because the tanks are designed to fit into a particular gun, not to be used standalone.

So I'd start at an industrial gas company and ask them about their smallest size containers, and if their sizes aren't what you need, go to the paintball suppliers next and see if they have any standalone tank systems that could be utilized. Don't try to rig things, at 1000psi things can get very ugly if something fails. Also, the CO2 supplier is only going to put CO2 into an approved tank, with a current hydro testing seal, so if you try to get creative nobody will fill it for you anyway (same with dive shops and plain air).

Well, dwalby gave you the math. Go to a paintball store and see what they have. I'm looking at a 62 cu inch paintball tank shaped like a scuba bottle. It is 3.25" dia x 12" high. I'm sure the paintball guys can either get you parts or tell you where you can get them to make the hookup (dont forget the regulator). My bottle is pressurized to 3000 psi - just like a scuba tank, and has to be hydro tested every 3(?) or 5(?) years. Since it might have a tendency to explode if overheated, keep it on a cool part of the bike - you don't want to be around if it does pop. In a pinch, you could always shoot the random rodent with your paintball gun.....

The paintball shop can fill it with either CO2 or nitrogen (air).

playinatwork said:

The compressor takes way too long.

Click to expand...

What's your definition of too long?

--Mark

Here's a floor pump that seats bicycle tubeless tires.

http://www.bikerumor.com/2014/09/15/just-in-bontrager-tlr-flash-charger-floor-pump-skips-the-compressor-for-tubeless-tires/

They said it seated the bead on a mountain bike tire (I think a 26" X 2.35") and left it with 35psi. Who knows if it would work on a motorcycle tire.

SMSW said:

I'm sure the paintball guys can either get you parts or tell you where you can get them to make the hookup (dont forget the regulator). My bottle is pressurized to 3000 psi - just like a scuba tank, and has to be hydro tested every 3(?) or 5(?) years.

Click to expand...

So I'm assuming from your post that you are currently using this for a paintball gun? What's the neck of the bottle look like, standard threads that would accept a valve/regulator, or something else that fits into a paintball gun receiver? Does it look like it would be easy to attach a valve/regulator onto the neck?

BTW, is your forum name SingleMaltScotchWhisky, or is that just a coincidence?

check this link, its a homebrewing store, they have the paintball tanks, regulators, and adaptor.

Looks like all 3 for about $90 + tax, maybe even a little less, there's different options available.

http://www.homebrewing.org/The-Adapter-CO2-regulator-to-Paintball-Tank-Adapter_p_1122.html

Also, I did a little websearching and it looks like scuba tanks are designed to handle overpressure from heat up to 65C, not sure about the paintball tanks though.

dwalby said:

So I'm assuming from your post that you are currently using this for a paintball gun? What's the neck of the bottle look like, standard threads that would accept a valve/regulator, or something else that fits into a paintball gun receiver? Does it look like it would be easy to attach a valve/regulator onto the neck?

BTW, is your forum name SingleMaltScotchWhisky, or is that just a coincidence?

Click to expand...

Bottle looks exactly like a miniature scuba tank with threads to mate w/ a paintball gun (aka deer chaser) and what looks like a schrader valve on the side, except said valve has no external threads but a narrowed neck where the dealer clips his hose. The tank stays on the gun when they are filling it. Since they sell long high pressure hoses and a harness so you can wear the bottle (like a paper boy's sack or a bike messenger's pack (Aerostitch sells one of the latter)) and connect it to your paintball gun, I would think parts must be readily available so you could use it to inflate tires. My tanks (both of them) have tiny pressure gages, probably accurate to the nearest 200 psi. They are only about 5/8" in diameter and serve mostly to let you know you have no air after your paintballs dribble out of the barrel. My wife loved the deer tramping thru our yard until they discovered her flowers and garden. Then they became unwanted rodents overnight. I asked the local constabulary if I could shoot the deer w/ a paintball gun and was told that we have a lot of colorful deer running around our fair city. I guess that means yes. I'll take a pic later and post it.

Yes, SMSW comes from that. A teacher and friend of mine absolutely loved one called Glenfarclas. So, several of us got together and bought him a bottle of the 25yr aged variety. He opened it, pulled out his bottle of 12 year whiskey and poured each of us a shot to compare and learn exactly what smooth whiskey tastes like. He sipped the 25 yr variety and closed his eyes, swished the stuff around in his mouth, smiled, and looked completely relaxed and happy with a beatific smile. My friend Rick tasted the Glenfarclas next. He too, swished it around, smiled, closed his eyes and enjoyed the taste. Now, my father had done the same thing with cheaper whiskey many years before this and had offered me a taste. I sipped. The only explanation I can offer is that some people are born with many taste buds per square centimeter on their tongues (so called super tasters - one is employed by the City of New York to taste the water) and some people have fewer taste buds. I must be in the latter group. This $150 a bottle whiskey tasted to me like last year's used turpentine. It was all I could do to not act like your professional wine taster and spit it out. I guess I will never know how some things taste. The difference between the 12 and 25 yr old whiskey was obvious, even to me. The younger variant burned as it went down my throat, the 25 simply felt warm and nice - no burning. But it did not taste good to me. All this happened about 20 years ago, when I was not quite 50.

dwalby said:

Also, I did a little websearching and it looks like scuba tanks are designed to handle overpressure from heat up to 65C, not sure about the paintball tanks though.

Click to expand...

The paintball tanks are subject to the same rules and laws that scuba tanks, and all high pressure gas tanks (oxygen, nitrogen, helium, etc). As I said, they have to be hydro tested which costs around $45 at the one place I checked. This makes the tanks almost throw aways since you can get one on fleabay for around that much (used) or $60 new. Obviously not so for a several hundred dollar scuba tank or tall gas tank. My point was, just be careful with this thing. Gas at 3000 psi stores a lot of potential energy and should the tank fail, somebody could get hurt badly. Scuba tanks that exploded have killed people.

Personally, I don't like the idea of carrying around a fully charged tank - but that's just me. As for seating a bead on a tire, if you have a ratchet tie down in your emergency tool kit, just run the webbing around the tire, hook the two hooks togther, snug up the webbing and make sure it is centered on the tread pattern of the tire. Crank the ratchet tight and add air. This is how mechanics seat some tires' beads, tho they use an inflatable hose that clamps to itself around the tire. They add air, it presses inward on the tread, and the beads naturally spread apart.

SMSW said:

A teacher and friend of mine absolutely loved one called Glenfarclas. So, several of us got together and bought him a bottle of the 25yr aged variety. This $150 a bottle whiskey tasted to me like last year's used turpentine. It was all I could do to not act like your professional wine taster and spit it out.

Click to expand...

its one of my faves

What I do...

Start with a good quality small bicycle pump to about 25 psi them move on to small compress air cartridge. In a bicycle shop you can find some cartridge that are bigger and hold about three small cartridge.

Works good on a rear tire but you need to have time and patience.

Wow, thanks for all the help guys. Do you think this would hold enough air to seat a bead once? I think it would be fine for topping off the bike when I have to plug a tire. It never has been totally flat when I have to stop and put in a plug so there's some air already in it.
http://www.ebay.com/itm/Trinity-Co2-Regulator-Kit-with-20oz-Tank-for-Air-Tools-Carpenter-Nail-Gun-roof-/111879978095?hash=item1a0c90fc6f:g:-pMAAOSwpRRWnoqB

I have seen a tires bead set with a portable 12 v compressor.

Tim, do you have that many flats that this is worth it? I figure if I can't plug it and pump it up with my 12V compressor, that's what my insurance towing program is for. No way I'm going to break it down on the side of the road to patch it.

Now, if you're in the 'back country', that's another story.

Sorry to say, yes I do get that many punctures. I average almost 1 a month. My bike is my daily driver and I work in an industrial area. There's a roofing supply yard across the street from work and some rough RR tracks a block away. My last PR4 rear had 7 plugs in it before I ran out of tread. I get about 10k miles out of a rear tire and average about 2.5k miles/month.
I've gotten pretty adept at pulling nails and plugging tires. Then I just stand and wait for that noisy little pump to do its thing.

playinatwork said:

Sorry to say, yes I do get that many punctures. I average almost 1 a month. My bike is my daily driver and I work in an industrial area. There's a roofing supply yard across the street from work and some rough RR tracks a block away. My last PR4 rear had 7 plugs in it before I ran out of tread. I get about 10k miles out of a rear tire and average about 2.5k miles/month.
I've gotten pretty adept at pulling nails and plugging tires. Then I just stand and wait for that noisy little pump to do its thing.

Click to expand...

Wow, I've not had one in years. Mine is my daily driver too but my average monthly mileage is only about 1/2 yours, plus I don't have the local industrial/roofing supply issues you have. With your tire plugging experience, you're the guy I want to ride with on long trips!

Good luck with finding a solution that works for you. Have your thought about a car tire for the rear? Would that even help?

Thanks Paul. I have tried using a car tire and it hardly ever picks up the nails; weird. I've done about 35k miles on a car tire and I really prefer bike tires. All that said, I'll likely go back to a car tire because of this and the extra mileage.

jfheath said:

What this has to do with tyres and compressors, I don't know. Sorry.

Click to expand...

Standing alongside the bike in the dark night rain waiting on that slow compressor makes me want to think of better things like a SMSW... and an alternative to the slime pump.

playinatwork said:

Wow, thanks for all the help guys. Do you think this would hold enough air to seat a bead once? I think it would be fine for topping off the bike when I have to plug a tire. It never has been totally flat when I have to stop and put in a plug so there's some air already in it.
http://www.ebay.com/itm/Trinity-Co2-Regulator-Kit-with-20oz-Tank-for-Air-Tools-Carpenter-Nail-Gun-roof-/111879978095?hash=item1a0c90fc6f:g:-pMAAOSwpRRWnoqB

Click to expand...

I had trouble with the link earlier, then forgot about it until now. Yes, this is exactly like what we've been talking about, and similar to the link I sent you in the earlier post. This one looks even better because the gauge is integrated into the regulator so you don't have as many things sticking out from the neck of the tank, making it easier to store, and less likely to snag on something.