Track Tac

Big track gearing with minimal speedloss.

flattop1 said:
A single kart trying to pass a group off the corner is gonna be tough .
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This is very true. I have gotten runs down the straights and into the corner showing my nose up to the seat then center off it's like everyone finds 3 or 4 mph while I'm just looking at the rear again lol
 
Mconnell22 said:
Yes sir drop is center off. Kart is snappy loose
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If you cannot keep the nose down, then the additional steering input will make kart snappy loose.
Do you have a newer rr to put on to try?

Or add some lf positive camber. Remove a little cross.

Just some ideas.
Some of the others will maybe have better idea for asphalt.
 
95 shaw said:
If you cannot keep the nose down, then the additional steering input will make kart snappy loose.
Do you have a newer rr to put on to try?

Or add some lf positive camber. Remove a little cross.

Just some ideas.
Some of the others will maybe have better idea for asphalt.
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Hey I'll try anything at this point.
 
mike97760 said:
So its a chassis setup problem. I dont own any gears that will fix that.
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I'm leaning on that now after seeing all the input. You guys are awesome. I do not regret posting here about it. Yeah the grip makes sense if I'm 4 wheel sliding I would lose speed and drop rpms.
 
Drop air PSI to 14# rights to more what the tires are designed for. 25# will make the kart bounce and snappy.
Reduce left side at least 1% to plant those old dried out tires and get off LR past the center, raise cross to a more reasonable level, maybe match left side%. Your 47% is reducing weight on LR but the whole platform is out of balance. Measure tire temps to see which tire is doing all the work.
Reduce LF positive camber to maybe 0* or even slight negative. Camber gain in LF will cause the kart to snap loose with the slightest steering input especially when trying to cut under someone OFF the corner. Once again work on aero !
Don't be afraid to experiment moving the hubs on the rear to change weights on the rear tires, a little goes a long way.
Be sure your brake is not dragging in the turns.
At 5700RPM with your 3.44 gear ratio you're only running 53 MPH so every little gain is huge.
If you get the kart rolling free'er you may drop the gear a few tenths,,, BTW a 21/68 is a 3.24 ! And that's 57MPH.

Best, WP
 
WPaul said:
Drop air PSI to 14# rights to more what the tires are designed for. 25# will make the kart bounce and snappy.
Reduce left side at least 1% to plant those old dried out tires and get off LR past the center, raise cross to a more reasonable level, maybe match left side%. Your 47% is reducing weight on LR but the whole platform is out of balance. Measure tire temps to see which tire is doing all the work.
Reduce LF positive camber to maybe 0* or even slight negative. Camber gain in LF will cause the kart to snap loose with the slightest steering input especially when trying to cut under someone OFF the corner. Once again work on aero !
Don't be afraid to experiment moving the hubs on the rear to change weights on the rear tires, a little goes a long way.
Be sure your brake is not dragging in the turns.
At 5700RPM with your 3.44 gear ratio you're only running 53 MPH so every little gain is huge.
If you get the kart rolling free'er you may drop the gear a few tenths,,, BTW a 21/68 is a 3.24 ! And that's 57MPH.

Best, WP
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Man you just totally took me 180 in set up. I will revisit this post again soon . I will balance it 50/50 and change that gear. Will set up a practice day soon enough . I will go to lower pressures and reset the camber to zero out. If I can just get more stable and not slide I believe that will be a big deal
 
If you add cross %, be sure to lower the left side, this will load the rights more. On a banked paved track the left side is loaded more than on a flat track. The extra cross just makes the kart distribute the weight and have more of a stable feel.
You can put a 4.50 or 5.00 on the LR, I'm thinking you have seen that already. On a 3/8's paved track you won't need a lot of stagger so be careful with a small tire on the LR. Fix the stagger. As soon as you come off the track lay your hands on the rear tires,, don't be surprised if the LR is a lot hotter than the RR.
Your 47% cross is causing the RF to be light, not loaded, especially when the kart sits down on the LR from center off causing your push off the corner. Don't add nose weight, it will only make it worse !
Now ! A little something about gear ratios on big tracks. You can turn 5700RPM with a 3.44 gear and you just may turn 5700RPM with a 3.24 gear,, all else being the same ! Just 4 MPH faster. But the kart can NOT be in a bind.

Hope this helps you out, Best WP
 
WPaul said:
If you add cross %, be sure to lower the left side, this will load the rights more. On a banked paved track the left side is loaded more than on a flat track. The extra cross just makes the kart distribute the weight and have more of a stable feel.
You can put a 4.50 or 5.00 on the LR, I'm thinking you have seen that already. On a 3/8's paved track you won't need a lot of stagger so be careful with a small tire on the LR. Fix the stagger. As soon as you come off the track lay your hands on the rear tires,, don't be surprised if the LR is a lot hotter than the RR.
Your 47% cross is causing the RF to be light, not loaded, especially when the kart sits down on the LR from center off causing your push off the corner. Don't add nose weight, it will only make it worse !
Now ! A little something about gear ratios on big tracks. You can turn 5700RPM with a 3.44 gear and you just may turn 5700RPM with a 3.24 gear,, all else being the same ! Just 4 MPH faster. But the kart can NOT be in a bind.

Hope this helps you out, Best WP
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This all sounds very plausible. I hate 4.50 on left's and 6.00 on rights . I have a big weight in the nose . I'm probably the only driver that can be in my kart and weigh 450# with that one nose weight . So I probably need to move it to the left side anyways .
 
Mconnell22 said:
This all sounds very plausible. I hate 4.50 on left's and 6.00 on rights . I have a big weight in the nose . I'm probably the only driver that can be in my kart and weigh 450# with that one nose weight . So I probably need to move it to the left side anyways .
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The weight on the nose will make it push, best to mount it to the seat. Cut it in half,, half on each side.
You haven't said what brand kart or the details of your set up,, might help.
Take a good look at the RF negative camber. With 25# of air that tire doesn't flex at all and with ,,say,, -3* camber your only running on a narrow ribbon of tire. The tire won't flex much at 14#, so more like -2* or maybe less. Make a chalk mark across the RF tire to see how much tire surface you are using after you make a practice run. As you get close to using the whole face of the tire the kart will begin to get twitchy, a bad thing, you'll need "some" RF negative camber but more is not necessarily better. Take a good look at your right side tires, one may be better on the RF than the other,, close looks !
Once again, this is all a combination. There's a lot of speed to be gained from just what you have told us, but it comes in small pieces.

Best, WP
 
WPaul said:
The weight on the nose will make it push, best to mount it to the seat. Cut it in half,, half on each side.
You haven't said what brand kart or the details of your set up,, might help.
Take a good look at the RF negative camber. With 25# of air that tire doesn't flex at all and with ,,say,, -3* camber your only running on a narrow ribbon of tire. The tire won't flex much at 14#, so more like -2* or maybe less. Make a chalk mark across the RF tire to see how much tire surface you are using after you make a practice run. As you get close to using the whole face of the tire the kart will begin to get twitchy, a bad thing, you'll need "some" RF negative camber but more is not necessarily better. Take a good look at your right side tires, one may be better on the RF than the other,, close looks !
Once again, this is all a combination. There's a lot of speed to be gained from just what you have told us, but it comes in small pieces.

Best, WP
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All good info here. Definately do not want to be twitchy
20220426_181710.jpg

WPaul said:
The weight on the nose will make it push, best to mount it to the seat. Cut it in half,, half on each side.
You haven't said what brand kart or the details of your set up,, might help.
Take a good look at the RF negative camber. With 25# of air that tire doesn't flex at all and with ,,say,, -3* camber your only running on a narrow ribbon of tire. The tire won't flex much at 14#, so more like -2* or maybe less. Make a chalk mark across the RF tire to see how much tire surface you are using after you make a practice run. As you get close to using the whole face of the tire the kart will begin to get twitchy, a bad thing, you'll need "some" RF negative camber but more is not necessarily better. Take a good look at your right side tires, one may be better on the RF than the other,, close looks !
Once again, this is all a combination. There's a lot of speed to be gained from just what you have told us, but it comes in small pieces.

Best, WP
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2012 shadow envy champ kart .
 
WPaul said:
The weight on the nose will make it push, best to mount it to the seat. Cut it in half,, half on each side.
You haven't said what brand kart or the details of your set up,, might help.
Take a good look at the RF negative camber. With 25# of air that tire doesn't flex at all and with ,,say,, -3* camber your only running on a narrow ribbon of tire. The tire won't flex much at 14#, so more like -2* or maybe less. Make a chalk mark across the RF tire to see how much tire surface you are using after you make a practice run. As you get close to using the whole face of the tire the kart will begin to get twitchy, a bad thing, you'll need "some" RF negative camber but more is not necessarily better. Take a good look at your right side tires, one may be better on the RF than the other,, close looks !
Once again, this is all a combination. There's a lot of speed to be gained from just what you have told us, but it comes in small pieces.

Best, WP
Click to expand...
I'm 2.5 degrees camber in rf...plus 1 notch on caster. 47% cross....49 %nose
LF is 2.5 degrees camber ...plus 1 notch on caster
Rear is axle is skewed slightly like a sprint car with right side forward 1 inch
 
Mconnell22 said:
I'm 2.5 degrees camber in rf...plus 1 notch on caster. 47% cross....49 %nose
LF is 2.5 degrees camber ...plus 1 notch on caster
Rear is axle is skewed slightly like a sprint car with right side forward 1 inch
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Not near enough in RF, and if what you posted for LF 2.5 that's way to much, 49% nose is to much as well.
 
Nice looking kart.
A few other things: If you feel like you’re experiencing wind buffeting in the turns,, it’s not ! ,, it’s the stagger is wrong. What you’re feeling is one or both tires are slipping to Compensate. Your stagger will be 0” to 5/16” on that big high banked track.
Take one of the upper bolts out of the seat,, if the seat is “sprung” fix it. A seat that has the kart in a bind will even affect straight-a-way speed. Be sure to put the bolt back in after you line it up. With a 200+# driver there’s a lot of leverage.
From memory I think a Shadow is a high cross% kart. You might find more cross will actually free it up.
I sincerely hope all this helps you out. Do us here on Bob’s a favor,,, post back what results you find. That’s all we get for helping you out.

Best, WP
 
We got the seat @8 inches now . Just right. Turns well. Zero on caster and .5 on camber. Went to 63% on cross. So went higher. Changed the gearing on front to a 21 to make the 3.44 ratio and wow. Came alive. Motor didn't struggle. Kart turned and exited with little to no steering input. Kept straightaway speed . Also went back down to 14 psi from the 22 psi plus that I was running. 1 inch stagger . Just wow thank you all for your help. Also removed nose weight and put on left side
 
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