Nitrogen vs Air

So as I am planing out the build of my new trailer I was thinking about making the switch to nitrogen for the smaller footprint. Anyone do this? Pros and cons? I get the pros of nitrogen filled tires as I did it in my car racing days But with no way to back purge kart tires it’s really a meh point.

Makes a little difference, but not a deal breaker. I know lots of really top-tier guys who run air.

We have a vacuum to suck all the air out after beading tires, and then have a nitrogen bottle to fill them back up.

Very little difference between Air and Nitrogen and on the surface very little difference when it comes to how it will react when racing. However, that is taking moisture out of the equation and moisture is very common in compressed air! Humid air takes longer to heat but retains more heat and water expands much more with heat then air and it will make tire pressure fluctuate as a result vs nitrogen. The main issue, filling with air isn’t consistent you fill on a cold dry day vs a hot humid day and the air inside the tire will not be the same ans will react differently. Do you run into situations where having humid air in a tire can be helpful? Hell yes… but you better have an engineer that understands exactly what your trying to achieve.

That is why Nitrogen is helpful keeps your air consistent and that can be very helpful.

Racecar tires maybe, trailer tires, I doubt it very much if it would make any difference. They just don’t get tAs hot as race car tires.

When you mount a tire, it has air in it, and moisture, depending on the humidity. Using nitrogen doesn’t get rid of that moisture. Nitrogen is no better than dry air. I use to fill my air bottle with my compressor, I never saw any moisture in my air bottle!

Any thread discussing nitrogen vs air for kart tires, deserves to have at least one comment pointing out that if you’re not balancing your wheels - it’s time to review priorities. :grin:


Tj once piped up on that. IIRC he said it was only a sometimes thing. It sure doesn’t hurt. The wheels don’t spin very fast.

Not sure I agree. Most kart racers find more time over the course of a run with dry air or nitrogen in long races or hot days vs balancing their wheels.

Even in road racing where speeds are over 100mph, balancing is important and you can feel it. But I’d be more worried about tire temps on a hot day in a 25min race.

To each their own, and do both I guess if want to cover all the bases, but there seems to be a LOT more empirical support/advice for balancing kart wheels vs using nitrogen in them. Personally, I don’t mount wheels on the kart that aren’t balanced.

It’s situational, like anything.

I’m listening… Not saying I vehemently disagree or anything… Just curious what you’ve found.

Umberto Merlin told me it was worth 0.3 to balance your wheels.

Personally, I would do it anyway just to not lose my fillings at the end of the straight at New Castle or GoPro.


Surely it depends on how out of balance they are :man_shrugging:

Or the track average speeds, the class, the tire, the weight…

Presumably with the language barrier he found it easier to just say “three tenths” and point me to the wheel weights. :sweat_smile:


For the most part it just takes out another variable. On the Porsches, we have a humidity tester that we check every tire while purging. Normally two purges will get it close, but the magic number is under 14% humidity. It just helps keep the rate of growth a constant. But that’s with a lot more volume of air. In karts the volume is lower but that means the sensitivity increases. 0.5Psi variation on a car tire at 28psi target is a much smaller percentage than 0.5psi on a kart tire at 10psi. Is it noticeable? Probably not. But it would help eliminate pressure variations due to humidity.

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So, how many tenths was it in the end?

Appreciate it fellas. Time to get a bottle and regulator on the way. I think if anything it’s a much smaller footprint

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What did you decide on?

I don’t balance my wheels, I’m lazy, but damn if you can’t tell they’re out of balance about halfway between I70 and turn one at New Castle in a shifter! First time there in one, I thought something was about break and kill me. :joy:

I don’t know, but I won the race that day.

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Success. I am guessing it gets more relevant the longer the straightaways and the higher the speed.

I figure you might as well balance the wheels. It’s something cheap and easy to do.