Kartin’ kid
Active member
I have a set of Unilli 12x9 slicks mounted on 10x6 wheels and I was wondering what the correct psi is for a setup like that. I’ll be driving exclusively on asphalt and concrete if it matters
Tire inflation help
- Thread starter Kartin’ kid
- Start date
Functional Artist
Well-known member
Most tires have the proper inflation pressure, right on the side of the tire (the Unilli's that I had on my Excalibur kart did) 
...or check on the specs with the place from where you bought them
...or even just Google tire inflation pressure for Unilli 12" x 9" slicks
...or check on the specs with the place from where you bought them
...or even just Google tire inflation pressure for Unilli 12" x 9" slicks
Rat
Well-known member
General rule of thumb is that the smaller the tire is the higher the PSI it needs.
I'd estimate you'd want 50 to 60 psi. A trick that hasn't failed me (or a tire) yet, is to air it up till it's hard to squeeze and then add rider/driver weight to the cart (or bicycle, minibike, etc) this trick only works on anything smaller than a fully dressed Harley Ultraglide classic (1800lbs) and
If the tires squat add more to the nearest 0 or 5 that makes them look right while the extra weight is on. Some squat is normal obviously, but not if it's scrubbing sidewall parked.
I'm sure someone who actually knows will be with you shortly, Denny seems to stalk me
I'd estimate you'd want 50 to 60 psi. A trick that hasn't failed me (or a tire) yet, is to air it up till it's hard to squeeze and then add rider/driver weight to the cart (or bicycle, minibike, etc) this trick only works on anything smaller than a fully dressed Harley Ultraglide classic (1800lbs) and
If the tires squat add more to the nearest 0 or 5 that makes them look right while the extra weight is on. Some squat is normal obviously, but not if it's scrubbing sidewall parked.
I'm sure someone who actually knows will be with you shortly, Denny seems to stalk me
Rat
Well-known member
That is standard practice, no matter the manufacturer or intended design use, but I have seen a few tires here and there where the only option was guessing and loading to squat check
Kartin’ kid
Active member
Googled it, found nothing. On almost every tire it does say on the side but you’ll notice that it says MAX INFLATION. this is not what you want to inflate your tire too, simply the maximum amount of pressure before you are in danger. Same rule for full sized car tires. Never permanently inflate one to max inflation. As for checking where I bought them, I thought I did but I’ll look againMost tires have the proper inflation pressure, right on the side of the tire (the Unilli's that I had on my Excalibur kart did)
...or check on the specs with the place from where you bought them
...or even just Google tire inflation pressure for Unilli 12" x 9" slicks
Denny
Canned Monster
With racing slicks the lower and squishier the better usually. What you want to do is take a piece of blackboard or sidewalk chalk and air down until you get wear across the tread of the tire. Nice even wear. Start at around 20 lbs and go up or down from there. The little holes in the slicks are wear indicators.
Rat
Well-known member
^Basically dust the ground and see what sticks where on the tire.
To much psi bulges giving a single center contact patch , To low will cup so there'd be a contact stripe towards both edges.
A wide center stripe (85% of the total tread width) while the cart is empty, usually squishes to become full contact with an added driver
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Karttekk
Well-known member
Unilli's site has the correct PSI for their tires. Not sure which tire you have but the specs for each tire are posted.
Denny
Canned Monster
Wow, those tires are a lot lower pressure than I would have thought.
anderkart
Moderator
Most all brands of Racekart slicks run low air pressure.
Yours are rated for 7 lbs. max:
Yours are rated for 7 lbs. max: