Outlaw kart bouncing

R

racinnut15xm

Member
Got a panther kart that is very close to a qrc. Lower frame is 1 1/8 tubing. Driver is about 240, race ready kart is about 500, has 450 crf, driver is tallerish say 6 2. We have done alot of stuff to try to get the bounce out of it. Running hoosier treads 50 RR required.

Is it possible the driver is just too big and COG too high for the 1 1/8 frame? We adjusted the camber and it looked good when he was out of the kart and once he gets in the LF goes from positive to negative.
 
One Can say with certainty the bounce is caused by slip grip, slip grip, slip grip, creating a rythum, now the million $$$$$ question is what's causing the slip grip, I'd say yes it could be to high VCG, also I know nothing about these karts but if LF is supposed to be positive I would think that would need set with the driver in the kart.
 
racing promotor said:
One Can say with certainty the bounce is caused by slip grip, slip grip, slip grip, creating a rythum, now the million $$$$$ question is what's causing the slip grip, I'd say yes it could be to high VCG, also I know nothing about these karts but if LF is supposed to be positive I would think that would need set with the driver in the kart.
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i agree thats typically the way its done. We put the max camber block on think its a 4 and it still ended up at negative on the LF. It seems to be ok for about a lap or two and steadily gets worse i'm guessing the tires are starting to grip more after the first couple laps. Moving the axle back seemed to help some but killed forward drive. It looks like its lower or laying on the RR more than the others, i went back and watched one of the videos. if VCG is too high raising the rear ride heights will only make it worse right? Or if its bottoming out it could be causing the slip grip you are talking about.
 
if it's 'really' just bouncing then throw some air to the tires to bounce over or across some of the bumps in the track.

But if like racing promotor offered a tire or tires are gripping and releasing then we
"need to know which tires or tires are doing it".

sound like an ok question racing promotor?
 
What kind of percentages are the UAS or true outlaw style guys with treads starting with? I know we probably have too much rear % but you can't lay the seat down and the axle is all the way back. He's already 50#'s or so over weight
 
racinnut15xm said:
What kind of percentages are the UAS or true outlaw style guys with treads starting with? I know we probably have too much rear % but you can't lay the seat down and the axle is all the way back. He's already 50#'s or so over weight
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We ran well UAS locally on treaded rear tires with 120RF/LR and 60LF/RR

But.... back then not knowing about how to use stagger we ran just 1/4" stagger unloading the LR tire to get around turns.
Today that sort of setup racing dirt oval UAS or anything would make you a total toad.

Just throwing antiquated racing know how out for general info.
 
Before we started changing on stuff we had 55 LS, 63% rear, 45% cross(first time messing with a true outlaw kart so just rolled with it). I haven't had it back at my house on the scale stands to confirm but since then he moved the rear axle back about 4 holes and he took it to another guys place it showed this LS 56%, Rear 60, cross 49.

We moved the RR and RF out thinking it may of needed more LS weight thats where the gain came from.

Air on the back anywhere from 8/15 to 5/8 didnt seem to make much difference. Front i think he stayed around 8/12. i have a few videos i would gladly send to anyone who's interested. I feel its more of a LR bounce. Things that seemed to help taking the 10 left rear off replacing with a 30, moving axle back and engine forward to reduce rear%.
 
I'd start messing with Air to pin point where, first I'd add 2 to 3 lbs more to the LR see if it free's it up, second I'd add 4 lb split to both rights to confirm If it's right side tight, third I'd add some to both rear tires see what that does, you'll need to pin point where the problem is to fix it, then the more air you need to add to that area the more severe it is.
 
Well he sent me a photo as a bare frame and then it was for sale on facebook and gone within hours so new frame on the way, we will never know.
 
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