chaadster

Hey folks,

Does anyone have a good idea of which minimum air compressor specs are necessary to tackle any type of tubeless tire installation? I’m talking, of course, about SCFM (or CFM) ratings and max pressure, but also tank size, hose diameter, and any other details which might be pertinent to setting up a system which can handle not only skinny road tires, but large volume MTB and 650b formats as well.

I have an old Harbor Freight unit which I’ve used over the years to do 700x25c and 700x30c tubeless installs, but it has broken. There’s a leak somewhere, and it’s not pressurizing the tank. I also knocked off the muffler in the house move last year, and it’s really, annoyingly loud. It was loud anyway, by modern standards. So I’m out to replace it. I also want to switch my new 650b-wheeled bike over to tubeless, for which I have some fat 48c tires for. That’s a lot of air volume, and it got me thinking that I need to take more care in selecting a new air compressor, but I just cannot find any info on what seems like the most relevant specifications for the pump’s performance.

It would be great if there was specific info out there, e.g. “you’ll need 5 SCFM at 40psi to reliably seat a 2.2” tire,” and I’d be very appreciative if anyone could share that info or share where to find it.

I don’t know what my Central Pneumatic specs were, but I think it was a 5 or 6 gallon tank, and I have larger diameter hose on it, I guess the 3/8ths type, but certainly larger than that coiled plastic type you often see. It worked fine for those 30c Schwalbe tires if I recall correctly...

Anyway, how does all this stuff fit together so that I can have a solid, totally usable home compressor setup for the job? I love supporting my LBS— shout out to Juan, Trevor, and Jimmy at Motor City Bicycle in Ann Arbor!— and they’ve helped out on a few tubeless installation fails over the years (oh, don’t anyone dare suggest Prestacycle inflators! I paid good money for what turned out to be trash; fool me once, shame on you, fool me twice, shame on me...), but I’d really like to have the capacity to do this at home so that I can do it anytime I want.

TIA,
Chaad

aggiegrads

The deciding factors are tank size and max pressure. Pretty much any compressor sold will be able to get the job done. The smallest I have seen are about a gallon, with most being around 4-5. If you set the regulator around or just above the max pressure for the lowest pressure tire you are inflating, you should be able to seat the tire easily.

CFM capacity doesn’t matter. If the initial blast from the pressurized tank doesn’t get the job done, the electric compressor won’t help.

Mad Honk 

For $200-$250 you can get a Makita 2gal. that will handle most anything you throw at it. Dual outputs and a good regulator system. Takes up about 2 square feet of space. You can get a 25ft. air hose with a chuck on the end and use attachments for both Presta and Schrader. I put one in our co-o two years ago and it is still going strong. Smiles, MH

Pop N Wood

What aggiegrads said. Any compressor with a tank will work. A tank you charge up with a foot pump will work.

Iride01 

I wouldn't go for any compressor. You did say for any tubeless tire. And I've read of some that have claimed to have had to put more than 125 PSI in their tubeless tires to get them to seat properly before setting them to their much lower riding pressure. And I've had to do the same with some tubed tires, though not lately.

Though when more pressure is needed, a decent floor pump will get you to pressures many shop compressors will never get to. So for those times you can switch to a floor pump for the last bit of pressure if needed.

125 PSI is typical of many shop compressor and some max out lower. Though lately I have noticed quite a few claiming 150 PSI as their max. But that much pressure used to be hard wear and tear on a piston type compressor.

dsbrantjr

A foot pump with an integrated tank will also work, like this one: https://ride.lezyne.com/products/1-fp-prodr-v204

chaadster

Thanks for the replies, everyone.

Seems a bummer that there is not more specific understanding and guidance on this. I guess my approach will simply be to go with as much compressor as space and money affords, use the bigger hose (which I already have) and throw down the bucks for a proper, pro shop grade inflator head, which I guess is the Park unit. Arundel has a shop head which is half the price and probably good, even though it looks built off the same, junk grade chassis as all the cheap stuff, with some slightly up-rated bits in the head and “head pipe.” Also, the Arundel is presta only, and I’d like to streamline operations for car and kids’ bikes, so Park Tool it is...unless anyone knows of good alternatives?

Bill Kapaun

You may find the outlet on cheap compressors to be overly restrictive.
Replace with a commercial quality one.

Kapusta

This^^^

rosefarts

I ran an air stapler for a week while laying down tubing for radiant heat. It was the old style oiled compressor. You could see the bits of oil spray out.

No matter in this application because a slab of concrete got poured over the whole thing once finished.

I have to wonder what oil does to sealant.

That said, my personal compressor is oil free.

zen_

I use the pancake compressor from HF that's $40 with a coupon, and the $10 starter kit that comes with a hose, air duster, and various fittings. Compressor -> hose -> air duster -> barb -> hose cutoff old floor pump (ghetto chuck with the duster lever). Like others have said, the tire either snaps in on the first blast, or you have fix that before trying again, so the flow rating of the compressor doesn't really matter. I usually snap the tires in, put the valve cores back in while waiting for the compressor to refill, then air up the tires again to let them set at least overnight.

If you don't like noise, or ever want to run air tools, then it's probably worth getting a nicer compressor.

Kapusta

Something was wrong with that compressor. It should not be spitting oil out like that. I have has several and never had that happen. Heck, I need to ADD oil to most of my guns.

Kapusta

I used ro work as a carpenter. Used many different types of compressors.

These days I just need something for home including some remodeling. i got a Makita MAC700 and love it:

https://www.makitatools.com/products/details/MAC700

It is small (though heavy for its size). It is an oiled model, and surprisingly quiet. I can easily have a conversation over it runnimg.

chaadster

I’ve had the situation where the tire does not move up the shelf and set up on the initial blast, but with a couple of seconds of fiddling while running the air does, so I know there are situations with some rims and some tires where having a good, continuous flow of air makes the difference between success and more work. That’s why I believe a 1gal tank is too small...unless the compressor SCFM delivers enough volume behind it. I’m going to stick with something in the 4.5gal - 6gal range, probably.

chaadster

That’s a powerful little unit that it has damn near near the same CFM at 90psi as it does 40psi! Have you heard how quiet the new, oil-less twin piston units are, though?! I’ll be happy to move away from oiled units, if only to eliminate the need to keep compressor oil around. Makita’s 3gal oil-less twin is attractive; I love that the drain is right up front, which suits my ideal placement location perfectly. It’s also rated at just 60dB, which is really, really quiet.

HerrKaLeun

Most DIY compressors are rated at 90 psi since the air tools are 90 psi. The tank is the buffer since the compressor is too weak. So what the compressor can provide is not very relevant unless you are in an assembly line airing up tires. Tank size is important. I'd think 3 gallons would be the minimum.

I have a $50 compressor with 5 or 6 gallon tank from Aldi. Finished half my house with it, also comes in handy to adjust car tire pressure. Works fine, but is loud.

The above floor pump with tank may work on skinny tires, but I doubt it works for fat tires. Sometimes the tire loses quite some air before sealing. Cheating is easier with a compressor.

For regular adding air to the tire I just use a floor pump.

Atlas Shrugged

Not at all the case virtually any compressor with a storage tank will do.

Bill Kapaun

Ignore list since I doubt you have tested all cheap compressors AND apparently have no concept of the word MAY.

base2 

It's been my experience that if you can't set a tubeless with a floor pump, an air compressor is only marginally better. The limitation is how much air can flow through the valve stem balanced against the loss of loose fit before the bead can get set on the shelf.

IME: Some combinations of rim & tire are better/worse than others. ENVE 7.8's & GP5K TL work easy & simple with little more than a floor pump & some vigor. However, with Velocity A23 & Gravelkings no amount of 10 gallon air compressor, with 125 psi of pressure & time, patience, or manipulation, yielded a set bead.

The solution for the A23's & Gravelking situation was 6 full wraps of tubeless rim tape to lessen the air loss before the bead set. After that, a quick shot for a fraction of a second is all it took. Admittedly, this was a worst case scenario.

...So, yeah, any air compressor could work, it depends on tire fit on a given rim as much anything else.

FWIW, (& everyone here probably already knows this): Once the bead sets enough to hold pressure from the air compressor, STOP! Carry on to max with a manual pump until everything sets. It wouldn't be a bad idea to let the tires soak a while at pressure until you're certain all is well. Then deflate, inject sealant & re-inflate by manual means...There's just no sense in "burping" a hundred mil of sealant all over the livingroom furniture.

alo

I knew someone who ran the hose from an air compressor to an (empty) large gas bottle, then used the air from the gas bottle. It enabled the storage of a much larger volume or air, and less fluctuation of pressure.

No doubt most of you know already, but use different pressure for different tires.

Kapusta

No I have not heard the new twin piston oil-less units. 60 db is really quiet. I would look into that Id I was buying another one.

Kapusta

If you are referring to Makita MAC700 I posted.... it works brilliantly on Fat Tires.

It goes well over 90psi, but even a 1gal tank at 90 psi is plenty of air to set a fat tire.

Kapusta

If the only way to seat the bead is to fiddle with the tire while the air is still blasting through.... enough so that a small compressor can’t keep up... you really need to look at how you are taping the rims. Those tire beads are much too loose.

HerrKaLeun

I was referring to the Lezyene floor pump linked above.

Fat tires can be tricky depending on the exact fit. they also stretch as they age. Sometimes the tire is not close enough to the rim. Soap water helps lubricate, and sometimes I need to put an inner tube around the tire to press it down to get it closer to the rim. Sometimes they are easy, sometimes it takes me the full tank volume (as determined by when the compressor kicks in) before it seats.

It always works out in the end, but I never leave with the wish to have a smaller compressor and/or tank. My compressor can't keep up and pressure drops. So once the tank depleted below the threshold that triggers the compressor, I know i lost and need to wrangle the tire better.

Kapusta

Oh, right. You did say “floor pump”. I shoulda read better. My bad.