1/5 Mile Dirt Champ Kart Newbie Setup

Knightrider955

Knightrider955

Member
New to Karts. Bought my 13 yr old daughter a 2003 Rage Nitro Senior champ with a methanol animal. Raced 1/5 mile dirt with 10 degree banking. It was spinout city lol. Kart was super loose. I put it on the scales with her in it and initial numbers were Left 56%, front 39%,, cross 48%.. So after playing with tire pressure and adding some lead to the nose I got it to Left 56%, front 42% and Cross 54%.. Total weight 330 lbs. The problem is my rear stagger is 2 inches and front stagger 1.5 inches. Is that too much for 1/5 mile? Her left rear tire is 11.50x8-6 and her right rear is a 12x9-6. Left has 18 psi of air and the right has 10 psi. Should I get rear tires that are the same diameter and then start over? Fronts are both 11 inches.
 
Are you changing scale numbers by adjusting air pressure? If yes, that's not how it works.

Post some additional info as to what track, type of track (asphalt or dirt), and what tires you're running. Do you have baseline set up numbers from Rage?
 
Knightrider955 said:
New to Karts. Bought my 13 yr old daughter a 2003 Rage Nitro Senior champ with a methanol animal. Raced 1/5 mile dirt with 10 degree banking. It was spinout city lol. Kart was super loose. I put it on the scales with her in it and initial numbers were Left 56%, front 39%,, cross 48%.. So after playing with tire pressure and adding some lead to the nose I got it to Left 56%, front 42% and Cross 54%.. Total weight 330 lbs. The problem is my rear stagger is 2 inches and front stagger 1.5 inches. Is that too much for 1/5 mile? Her left rear tire is 11.50x8-6 and her right rear is a 12x9-6. Left has 18 psi of air and the right has 10 psi. Should I get rear tires that are the same diameter and then start over? Fronts are both 11 inches.
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With those numbers even with 2 " rear stagger most likely the kart had a bad push required to much wheel input then when it grabbed spin city as you put it, for 1/5 th mile momentum track even with a champ
1 1/8" rear stagger would be max , if it's a 1/5 th tight turns out of throttle a good bit 1 1/2"
Rear would be max, no you don't need rear tires same diameter, you need right sides same diameter, and lefts sized accordingly to get stagger your wanting, you size the tires that with 6 lb of air in the rights and 5 lb in the lefts they are what you need, you do not take air away or add until you got what you want , when you go on scales stagger needs to be set , scale with 6 lb rights 5 lb lefts then you move weight around as needed to get your % ages to achieve a good baseline set up, heads up wheel spacing, camber adjustments, will change numbers as well.
 
Lightning3 said:
Are you changing scale numbers by adjusting air pressure? If yes, that's not how it works.

Post some additional info as to what track, type of track (asphalt or dirt), and what tires you're running. Do you have baseline set up numbers from Rage?
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As posted earlier, it’s dirt track with 10 degrees banking. tires are Hoosier D30’s and yes I have rage initial setup numbers from rage and I’m currently within range except for the nose I’m about 3% shy. If air pressure is not how it works then can you explain to me what is how it works? I’m new and trying to learn.
 
racing promotor said:
With those numbers even with 2 " rear stagger most likely the kart had a bad push required to much wheel input then when it grabbed spin city as you put it, for 1/5 th mile momentum track even with a champ
1 1/8" rear stagger would be max , if it's a 1/5 th tight turns out of throttle a good bit 1 1/2"
Rear would be max, no you don't need rear tires same diameter, you need right sides same diameter, and lefts sized accordingly to get stagger your wanting, you size the tires that with 6 lb of air in the rights and 5 lb in the lefts they are what you need, you do not take air away or add until you got what you want , when you go on scales stagger needs to be set , scale with 6 lb rights 5 lb lefts then you move weight around as needed to get your % ages to achieve a good baseline set up, heads up wheel spacing, camber adjustments, will change numbers as well.
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So your saying make my right the same diameter? Easy enough, I’ll just put an 11” diameter on the right rear. The right front is already 11”. As for the left do the sell tires in 1/4 increments for the diameter? If my left rear was 10.750 and I was running the air pressures you mentioned would put me spot on. Sorry I’m just trying my best to understand how this all works. Thanks.
 
Knightrider955 said:
So your saying make my right the same diameter? Easy enough, I’ll just put an 11” diameter on the right rear. The right front is already 11”. As for the left do the sell tires in 1/4 increments for the diameter? If my left rear was 10.750 and I was running the air pressures you mentioned would put me spot on. Sorry I’m just trying my best to how this all works. Thanks.
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Current wheels being used for 99.9 % of all the karts that are dirt oval racing, the 2 right sides the RF an the RR are 10 " wide, the LR wheel is 8.5 " wide, and the LF is 6.5 " with all being 6 " wheels, ideally once mounted with and you set air to a common race pressure like 6 lb in the rights and 5 lb in the lefts, your 2 right sides would measure 34" diameter. Your LR would measure 32 1/2", and your LR would measure 32 1/2", that would be 1 1/2 " stagger front and rear, unfortunately that only happens once in a blue moon, 1 of the right sides will be 33 3/4" the other right side
34 1/8" , LF will be 32 1/4", the LR 32 3/4", so what one must do is either grow tires bigger , or shrink tires smaller, right sides are easier to do both, the 34 1/8" right side would be simple remove valve gut let set half a day , put valve gut back in air to 6 lbs probably be 34" , the 33 3/4" right side put tire tape around the tire air it up to 34 3/4" let it set at say 3 hrs let air down to 6 lbs and check diameter that will usually gain the 1/4" needed, there are many different methods that will work and the more there off the tougher they are to size, the LF at 32 1/4" air it up 1" bigger than needed heat it up pretty good let set till cool and check, usually you'll get that 1/2" needed, the LR 32 3/4" remove valve gut heat the tire really hot with a torch to hot to touch let cool completely sometimes you can shrink it getting the 1/4" needed the first time, once there sized and have a heat cycle on them as soon as washed lower air in the LFs to 2 lb, purge LRs
Of all air, add air to right sides 12 to 15 lb will usually hold there size, the way it's described in the other post is what one must do to scale, as air pressures to race cannot vary that much.
 
racing promotor said:
Current wheels being used for 99.9 % of all the karts that are dirt oval racing, the 2 right sides the RF an the RR are 10 " wide, the LR wheel is 8.5 " wide, and the LF is 6.5 " with all being 6 " wheels, ideally once mounted with and you set air to a common race pressure like 6 lb in the rights and 5 lb in the lefts, your 2 right sides would measure 34" diameter. Your LR would measure 32 1/2", and your LR would measure 32 1/2", that would be 1 1/2 " stagger front and rear, unfortunately that only happens once in a blue moon, 1 of the right sides will be 33 3/4" the other right side
34 1/8" , LF will be 32 1/4", the LR 32 3/4", so what one must do is either grow tires bigger , or shrink tires smaller, right sides are easier to do both, the 34 1/8" right side would be simple remove valve gut let set half a day , put valve gut back in air to 6 lbs probably be 34" , the 33 3/4" right side put tire tape around the tire air it up to 34 3/4" let it set at say 3 hrs let air down to 6 lbs and check diameter that will usually gain the 1/4" needed, there are many different methods that will work and the more there off the tougher they are to size, the LF at 32 1/4" air it up 1" bigger than needed heat it up pretty good let set till cool and check, usually you'll get that 1/2" needed, the LR 32 3/4" remove valve gut heat the tire really hot with a torch to hot to touch let cool completely sometimes you can shrink it getting the 1/4" needed the first time, once there sized and have a heat cycle on them as soon as washed lower air in the LFs to 2 lb, purge LRs
Of all air, add air to right sides 12 to 15 lb will usually hold there size, the way it's described in the other post is what one must do to scale, as air pressures to race cannot vary that much.
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Thanks for clarifying. I want to add that I run Hoosier treaded tires. Will that change any of what you just explained?
 
Knightrider955 said:
Thanks for clarifying. I want to add that I run Hoosier treaded tires. Will that change any of what you just explained?
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Somewhat yes but you'll still have Right sides, LR,LF, treads will have more roll out they will be tougher to shrink, the same principle apply to air pressures racing pressures are not just whatever.
 
Knightrider955 said:
As posted earlier, it’s dirt track with 10 degrees banking. tires are Hoosier D30’s and yes I have rage initial setup numbers from rage and I’m currently within range except for the nose I’m about 3% shy. If air pressure is not how it works then can you explain to me what is how it works? I’m new and trying to learn.
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I can't help much with the set up as champ numbers seem to vary quite a bit by manufacturer and age of the chassis. As you note the nose weight seems low. I also think your left side is low.

Ken points out the typical wheel sizes and roll out / circumference of the tires. It probably changes with you running treaded tires vs slicks. @CarlsonMotorsports usually has good input on treaded tires.

You need to figure out what air pressure range you want to run and stagger your tires using those air pressures. Then scale with the driver in the kart race ready (helmet, jacket, etc). You can adjust the position of the lead, engine mount, and seat to obtain the targeted scale numbers. Are you happy with the camber, caster, and toe settings?
 
Lightning3 said:
I can't help much with the set up as champ numbers seem to vary quite a bit by manufacturer and age of the chassis. As you note the nose weight seems low. I also think your left side is low.

Ken points out the typical wheel sizes and roll out / circumference of the tires. It probably changes with you running treaded tires vs slicks. @CarlsonMotorsports usually has good input on treaded tires.

You need to figure out what air pressure range you want to run and stagger your tires using those air pressures. Then scale with the driver in the kart race ready (helmet, jacket, etc). You can adjust the position of the lead, engine mount, and seat to obtain the targeted scale numbers. Are you happy with the camber, caster, and toe settings?
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Camber, castor, and toe are at the Rage set up sheet baseline settings. I figured that would be a good start. I only want about 3/4 rear stagger to start with on the rear and with currently running a 11.50x8-6 on the left rear and a 12x9-6 on the right rear its not really easily attainable. I think I'm going to put an 11x9-6 on the right rear instead and then stretch or shrink from there. Ive added 12 lbs of lead to the nose to increase the front percentage to 42%. I could add a little more I guess. You think 56% for the left is low? What do you think it should be? I could probably adjust the seat a little to increase it.
 
Check your seat placement. You may need to move it forward to get the nose weight you need. Also see where the bottom of the seat is in relation to the frame rails. I never set a seat lower than 1/2” from the bottom of the rails. The lighter the driver, the higher I set the seat. A 70-110lb driver I’d be even with the top of the frame rails.
 
Skidude said:
Check your seat placement. You may need to move it forward to get the nose weight you need. Also see where the bottom of the seat is in relation to the frame rails. I never set a seat lower than 1/2” from the bottom of the rails. The lighter the driver, the higher I set the seat. A 70-110lb driver I’d be even with the top of the frame rails.
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My daughter runs a full containment seat in her Rage so its definatly above the frame rails. Shes about 100lbs so I might be able to raise it up a bit more.
 
Knightrider955 said:
Camber, castor, and toe are at the Rage set up sheet baseline settings. I figured that would be a good start. I only want about 3/4 rear stagger to start with on the rear and with currently running a 11.50x8-6 on the left rear and a 12x9-6 on the right rear its not really easily attainable. I think I'm going to put an 11x9-6 on the right rear instead and then stretch or shrink from there. Ive added 12 lbs of lead to the nose to increase the front percentage to 42%. I could add a little more I guess. You think 56% for the left is low? What do you think it should be? I could probably adjust the seat a little to increase it.
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Good that your front end settings are to the manufacturers spec. I would make the necessary adjustments to achieve the nose percentage. I don't know this chassis but would typically target 58.5-60% left.

Was she snapping loose? Meaning it wouldn't really turn but once it started turning it wouldn't stop.
 
Lightning3 said:
Good that your front end settings are to the manufacturers spec. I would make the necessary adjustments to achieve the nose percentage. I don't know this chassis but would typically target 58.5-60% left.

Was she snapping loose? Meaning it wouldn't really turn but once it started turning it wouldn't stop.
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Actually kinda, It was spinout city when she would be coming out of a turn. Like the whole kart was completly loose. And it would start just after halfway through the turn.
 
Knightrider955 said:
Actually kinda, It was spinout city when she would be coming out of a turn. Like the whole kart was completly loose. And it would start just after halfway through the turn.
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Post pics of your kart so we know what you are working with. Typically a early 2000s champ doesn't like high cross more like 54.5-56.5. To give you an idea of how percentages have changed I would go on prc website( I understand you own a rage) and look at the setup sheets on the champ karts from early 2000s to present.
 
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