If you are doing any off-roading, overlanding, or touring you are quite possibly inflating your tires and deflating them from time to time. If you are not, there are a couple reasons to be doing so. Deflating tires can make the trail a more comfortable ride and deflation gives better traction by elongating the tire’s foot print. When you get back off the trail and on pavement you will need to air them back up to not cause damage to the tires and to maintain good road manners. Other times you might find yourself needing to air up your tires while doing a tire repair on the trail.

Getting air back in the tire is what we will explore today. There are three types of inflation devices we will explore: Portable air compressors, on-board air, and portable CO2 tire inflation kits.

The one I see regularly at trailheads is the portable air compressors. Portable air compressors normally are less expensive and provide a wide array of options.  I personally ran a cheaper Slime portable air compressor for a few years.

The CFM’s (cubic feet per minute) were listed at 1.9. I knew this did not meet the higher end systems. I compensated for this by buying two because of their cost. This was a decent system for a few years. By using the two compressors I was  airing up two tires at once. The tires would slowly air up but I generally found myself faster than people I was with using a more common name brand single air compressor. One reason this worked for several years for me is my consistency of having tires no larger than 33” tall on a majority of builds I have had. These types of compressors were at the time less than $100.00 each.

There are other portable air compressors  with similar performance. The Viar 450P Compressor is a quality-built compressor and boasts 1.8 CFM. The components, design, and features are observably better quality than those Slime compressors I used. The cost is approximately $340.00.

As see here

Another great option is the ARB CKMTP12. This air compressor is possibly one of the highest priced. Something to consider though with this system is the twin compressor design, a 4-liter air tank, and a Pelican style hard case which everything is mounted to internally. The air-compressor claims a whopping 6.16 CFMs. This compressor also has a 100% duty cycle. That’s a huge increase from what we have discussed. The quality and CFM’s you get come at a cost. This compressor kit is priced over the $800 mark.

As seen here

The down side to these systems is the need to store them away and then remove them when you are ready for use. The two Slime compressors I carried took 2 cubic square feet of space. Another issue is accessibility. By using this type of system, you have to make sure to not let them get buried when packing your vehicle. These units also need to be connected to the battery adding to the time for airing up. Not including the ARB unit with a 4-liter tank, they are not the fastest option for airing up tires.

The positives to these units are normally their cost. The majority of these units on the market are less than a couple hundred dollars. They are also portable. Having the ability to be moved from vehicle to vehicle is nice. There were times I would loan them to friends on the trail. It was also nice to to pass them back to those our convoy once I was done. I’ve also used it when traveling in our family vehicle on long trips.

The next type we will discuss is on-board air compressors. On-board air I feel is where you notice a significant difference. The first thing I appreciate about on-board air is the convenience. Having the compressor in an out of the way location makes it very easy to get to and never have to worry about making sure it isn’t buried when loading or unloading gear. The on-board air compressors are already wired in and have a switch available for you kick on when needed. These units typically have higher CFM’s than their portable counterparts. These can been designed quite elaborately. If you were to use an air manifold you could run lines to different areas of the vehicle to connect the air hose to, such as the front/rear bumper, wheel wells, or cargo areas. They are also very useful to actuate front and rear lockers if you were to add aftermarket lockers. 

Some other add-ons for OBA systems that add convenience are multi-tire inflation kits. 

Wits End has several solutions at their website.

Rago Fabrication has a solution which is very interesting called the “Wifey Air System.”

A non-plumbed system is available by Indeflate, imported by Adventure Imports.

The last system is CO2. I have used CO2 tanks very little. Compressed air is really phenomenal with its ability to air tires back up the fastest. I have not seen air compressors (portable or OBA) be as fast for inflation. The speed of CO2 is remarkable. Where it really shines is larger tires. When you have 35” tires or bigger there is a large amount of volume contained inside the tire. The best OBA system with a tank can not keep up with what I have seen with CO2 Tank kits. So why haven’t I went to them? It really goes back to space and convenience of the on-board air systems. When we take multiple vehicles on 7-10 day trips we try to make sure we have some redundancy of gear. On the last couple trips we had an open bed Tacoma as a gear/recovery/repair truck. We carried a CO2 tank kit with us and it was nice to have an additional option if necessary. CO2 tanks are good for several tire fill-ups. How many is dependent on the tire size and how much you are refilling them on each fill. People who use them love them. The costs of the tanks are approximately $250-$500 for pre-built systems. I know others have DIY’d them for cheaper. The refill cost and ensuring it is filled before leaving on a trip should be considered before you purchase. A minor leak on a tank could be miserable experience if you were in need of a tire repair or fill from near empty. CO2 and rubber tires also have an interesting relationship. CO2 permeates the rubber. Over time your tire will lose pressure from the CO2 escaping.   

All of these are great options dependent on finances, space, desire for ease of installation, tire sizes, and many other individual needs and wants.

If you can try a couple out before purchasing you might find one fits your needs you weren’t expecting.