The Options:
On some tubeless tires, sometimes, you can get by with just a track pump. The (old-style) Schwalbe Pro One tires were pretty good this way. A reliable system though, it's not.
It's pretty common knowledge by now that to seat the bead on many tubeless tires you need a big shot of high-pressure air, and a track pump just can't do that. Lezyne (Pressure Overdrive) and now Topeak (Joe Blow Booster) both make a hybrid track pump that incorporates a ~ 1 liter canister you can pump up to ~ 150 psi and then release all in one shot.
Both are decent systems, but a lot of work if you have difficulty getting the bead to seat on a tire. That 1 liter volume means you get 1 shot to get it right and then back to 50 pump strokes. You also have to guess how much pressure you're going to end up with, as over-pressurizing the canister in anticipation of the volume drop is required. They're also expensive, at $139 and $159 respectively and not general-purpose air-compressors for pumping up car tires or operating small pneumatic tools.
I air up my car tires on a seasonal basis, and might want to run a small pneumatic nailer some day, but airing up my Conti GP5kTLs was my primary use for an air-compressor, and I didn't need much. I did want a large enough tank though that I could produce several good shots of air to get a difficult tire to hold the bead, and that excluded the small pump-to-hose systems where there is no tank, or virtually none.
Compressor Setup:
I found a $60 Briggs and Stratton 3ga (11.3 liter) compressor (made in China and sold under 3-4 other names as well) at WalMart with 125 psi max pressure, pressure regulator, and all the hoses and fittings included. It's oil-less (you don't want oil in your tires), easy to carry and doesn't take up much space. Unfortunately, as I found out, the hoses and fittings are pretty much useless. You could inflate a football or beach ball with them, but for tires, useless.
A Presta valve internally is pretty darned small, so presents a lot of restriction to any air source. A CO2 cart can easily overcome this with 850 psi (yeah, really) at 70F (3,170 psi @ 140F!), but working with pump pressures you need to eliminate every possible restriction from the tank to the Presta valve.
Turns out, I'm not the 1st guy to figure this out, which is why Milton Industries created their HV (high volume) line of couplers and fittings. Many other mfgs now make comparable systems, like the Husky labeled system I got from Home Depot. Still, I like to give credit where due.
The best way to see for yourself how much of a difference it makes is to simply blow through a standard fitting and an HV one. Likewise, the 3/8" ID hose vs the 1/4" ID hose. I cut a 6", 12" and 18" piece of the blue 1/4" ID hose that came with the compressor, and blew through them each. WOW, I had no idea length had such a HUGE impact on volume. Try blowing through the rest of the ~ 15ft hose that's left. What an eye-opener.
Resolved to go HV all the way, I wanted to by-pass the pressure regulator as well, but there's no way to do that without putting in a "T" on the unregulated side of the gauge panel that the EMERGENCY pressure release is attached to. That should NEVER be taken out of the system, and as you can see, I did not - thus the "T".
After installing the "T", screw the HV coupler in one side, and the EPR in the other, and TEST IT by pressurizing the tank and then pulling on the lanyard ring. You should hear air escaping. If not, there may not be enough clearance between the tank and the EPR. If this ever fails the tank will EXPLODE. (the pump has its own pressure shut-off, so this is a fail-safe, but be smart and leave the safety measures intact)
I don't know if it's really necessary, but I drilled out the back of the air-chuck with a "large" drill bit to taper the air into the valve stalk. It helps, but don't get too crazy. By removing material you are weakening the chuck. Once done (or not) put some tape on the end of the Tektron hose's 1/4" fitting and tighten it up. Ditto for all the other fittings. Tape and tighten, assuming there's no pipe dope on the threads already.
Like with all compressors (vs canister systems) you now have a Schrader, not a Presta system (this system ROCKS for filling up car, motorcycle or Fatty bike tires equipped with Schrader systems) so you'll need a $1 part - an adapter. After you pour your sealant into the tire through the valve, install the Presta valve body and screw on the adapter. Once you've seated the bead and aired up the tire, remove the adapter and turn the valve closed. No hurry. You can leave the valve open overnight if you want, as the pressure keeps the valve from leaking.
If you follow the instructions given on my GP5kTL review, the 25mm tire drops tank pressure from 125 psi to an almost perfect 110 psi. Be a little careful with the 28mm not to go past 90 psi as the pressure limit is 94 but tank pressure will still be at ~ 105 psi. As soon as you get an initial bead seat, check the pressure on the gauge and then air up in small spurts to get to full pressure. If it's a new tire, expect a little stretch.
This little AC takes 4-5 minutes to come up to full pressure from an empty tank, so I usually plug it in and let it run in the garage while I put the tire on, put the sealant in through the valve, and roll the tire around to spread the sealant around. It turns itself off at 125 psi, so just let it run. Oh, and it's noisy, so I don't head for the garage until I'm ready to air the tire up.
There's a small valve on the bottom of the tank. It's there to drain water out of the tank. When you compress air you squeeze water out of it. That's a steel tank, so to avoid rust and pitting it's important to use this valve to depressurize the tank until the next time you need it. Tilt the tank to one side so the valve is at the very bottom of the tank.
For a total of $97 bucks this beats any canister pump system like a rented mule. Now if those drop in price to $50 I might have to rethink my position, but .... nahhhh.
HV Parts List:
You'll need some Teflon pipe tape/sealant as well, and a couple of good Crescent wrenches, one for the jaw and one for the hole in the end of the handle needed to turn the fixtures tight so the tape (or often-included pipe dope) seals up tight.
Merry Christmas!
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