Hoosier Treads basic air pressure questions..

[Mac_49]

I've read and read as much as I can but feel that most material is mainly aimed towards slicks so I'm hoping to ask a couple simple questions with these treads.

1/5 mile track, hard and dry and a no prep tire class. Literally come off the track and can't even wash them.

1. Is there a general "rule" or thought of when the day goes on into night and the track cools down, do tires generally go down in pressure to compensate? So far I'm running the same tire pressures at 5 in the afternoon as I am at 10 at night because I don't know any better.

2. Is there a certain "threshold" of where to much or to less of pressure and the tire will basically be worthless?
Example...I know most slicks run in the 3-5 lbs...but I'm assuming the treads would be worthless at those pressures? Same when going up in pressures? I'm running roughly 8-10 split and want to see if changing things up will help but don't need to completely try and race ridiculous pressures.

Hope to get some insight as every week is a new experiment I have to try but don't want to be wasting a test when it's common insight that I'm way outside the boundaries to begin with.

Thanks!!

 

[flattop1]

Yes , typically you would lower air .
We ran the burris in the 3-5 lb range on soft damp dirt .
8-10 seems pretty high and a big split .

 

[CarlsonMotorsports]

Depends considerably on the size of track.
Bigger tracks = higher air.
With treads, we're always on higher air than with slicks because we're trying to get roll speed, not more grip (we have too much grip already.)
If the car is in a four wheel drift (sitting on top of the track and not getting into it) in the corners, then lower your split to even up 8# & 8#. That will help considerably. If you need more sidebite, lower psi, or lower left side weight percentage.
For small tracks, start with 6# & 8#, and go from there.


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[Mac_49]

If the car is in a four wheel drift (sitting on top of the track and not getting into it) in the corners, then lower your split to even up 8# & 8#. That will help considerably.

Everyone in this class seems to have some sort of drift so I'm glad it's not just me. But some definitely have more of a bite than others. I know setup could be everything but I've had the kart scaled to the track recommendations and will start asking about adjustments there but want to start with tires and how to adjust them as the day/night goes on
I'll definitely give the split suggestion a shot.
Would you say that around 6 is the lower end of the "threshold" of the tire and anything lower wouldn't have any benefit?
What about high side of psi?
I'm hoping (if it's not to generalized) to get a range of low to high of where I should try to stay in and I can experiment based off of those limits?

 

[CarlsonMotorsports]

"Typical" air pressure for one track can be considerably different than another track.
That doesn't matter if we're talking about slicks or treads on dirt.
Smaller tracks = lower psi. Bigger track = higher psi. Again, generalizations.
If you're on 5/6 air with soft sidewall slicks, then typically you'll be on 7/8 with treads on the same track.
If you lack sidebite, keep dropping the right side psi until the car hooks, or you kill the roll speed, and then you have to make a decision.
(hint) more bite can be gained chemically while running higher psi and not killing your roll speed.
As the track gets dustier, you'll want lower psi for increased grip in the corners.
As the track gets cleaner, you'll want higher psi to decrease grip and rolling resistance.
Keep in mind with an under horsepowered kart (Predator, etc.) that you don't want to be dragging around flat tires.
Flatten the tires in your pick-up truck and see how much more HP it takes just to get the truck to move in your driveway. Karts are no different -- those low psi rob HP.

Try starting with 6 & 8, then adjust from there.
6/6 for dry slick and dusty. 8/10 when the track gets hard and fast.
Knowing a little about your track, I'd suggest staying on the low side - decrease split, I wouldn't be afraid to run reverse split in extremes.
Take lots of notes, and remember, a stop watch (Mychron) never lies.
If it's faster on the watch, it's faster on the track.

 

[Mac_49]

"Typical" air pressure for one track can be considerably different than another track.
That doesn't matter if we're talking about slicks or treads on dirt.
Smaller tracks = lower psi. Bigger track = higher psi. Again, generalizations.
If you're on 5/6 air with soft sidewall slicks, then typically you'll be on 7/8 with treads on the same track.
If you lack sidebite, keep dropping the right side psi until the car hooks, or you kill the roll speed, and then you have to make a decision.
(hint) more bite can be gained chemically while running higher psi and not killing your roll speed.
As the track gets dustier, you'll want lower psi for increased grip in the corners.
As the track gets cleaner, you'll want higher psi to decrease grip and rolling resistance.
Keep in mind with an under horsepowered kart (Predator, etc.) that you don't want to be dragging around flat tires.
Flatten the tires in your pick-up truck and see how much more HP it takes just to get the truck to move in your driveway. Karts are no different -- those low psi rob HP.

Try starting with 6 & 8, then adjust from there.
6/6 for dry slick and dusty. 8/10 when the track gets hard and fast.
Knowing a little about your track, I'd suggest staying on the low side - decrease split, I wouldn't be afraid to run reverse split in extremes.
Take lots of notes, and remember, a stop watch (Mychron) never lies.
If it's faster on the watch, it's faster on the track.

Thanks so much for the info! I'll definitely be trying all of this this coming weekend. I have nothing to lose so I can try basically anything to see what happens
It does make sense about what you're saying with the low hp so I'll keep that in mind and see what changes feel better.
I'll be bookmarking this thread haha!