Kart chassis lift vs grip

Just so let me get this right,
The more grip the kart has means less lift?(too much grip in kart?)
The Less grip the kart has means more lift?(Not enough grip in kart?)

@Noahkoenig134 I really donā€™t think there is a direct correlation between the two issues you have stated above.

A kart will often perform better through medium and slow-speed corners when the kart lifts the inside rear wheel properly. However, if the kart ā€˜hikesā€™ too much, the chassis can bind, and feel sluggish. Too little hike, and the kart may not rotate as you wish it to. The rate of lift, height of lift, and the rate at which the kart begins to set down the inside rear tire all governs how you ā€˜feelā€™ the kart flex in a corner.

Many karts on a ā€˜greenā€™ racetrack (little to no rubber) will ā€˜flat slideā€™ through high and medium speed corners, which means they are not lifting their inside rear tire at all. This was often how I liked to drive my kart, or how I liked it to handle, but other drivers like a lot of chassis hike and flex even in medium and high speed corners. Still, many drivers will find that a chassis that behaves this way may feel like it has slightly less grip, but drives more to their liking. Especially with a harder tire, tracks with little rubber, or lower-powered karts, this type of handling is common to seek.

On the very opposite of this extreme is having too much lift. This is when a kart is truly ā€˜over-gripped.ā€™ In extreme cases, the whole kart can bicycle, as the kart simply canā€™t flex enough to compensate and rotate through the corner with the grip the tires are producing, or trying to produce. Other times, the kart can ā€˜hop,ā€™ where the lifting or dropping of the inside rear wheel is inconsistent or not controllable. This creates a feeling of the kart shaking as it exits the corner, slamming the wheel up, or down, and generally being frustrating to drive.

Thereā€™s a lot of situation-by-situation instances in all of this.

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One thing Iā€™d like to expand on in Ericā€™s great postā€¦ Often times we will be trying to optimize the setup for the whole track, or trying to optimize the setup where there is the most time to be made up. For example, a kart that hikes nicely and rotates well in the really tight corners might have too much jacking in it for the faster corners. Iā€™ll often find that a kart that has a tad of understeer into the tight stuff is perfectly stable in the fast corners. And conversely, if the kart is a little loose in the fast corners, it might be perfect in the tight corners. At that point, we are splitting hairs, trying to move track widths in mm increments trying to get it balanced in both sections of the track. Sometimes you canā€™t quite get there, and you might have to deal with a kart that isnā€™t perfect in one section of the track to make the most of another section of the track. For example, if all your passing zones are in sector 1, you might have to adjust the kart setup slightly to make the most of sector 1, while giving up a bit in sector 2 or 3. Then you can make your passes and build the gap in the first sector and defend in the next two sectors if necessary.

Driver adaptability becomes super important here, because the really great drivers can take a kart that isnā€™t perfect in one section, and alter their driving to alleviate that, all while maintaining the kartā€™s perfection in another section.

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How do I drive to get the kart to handle like this? With a green track, low horsepower, and soft tires?

@tjkoyen learning how to adapt to what the kart is doing and where it is strong on the track is one of hardest things to learn. At least for me. Just tells me I need more seat time right?

Yup, just seat time, taking notes, reviewing data, reading, learning etc.

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I think it is worth pointing out there a 2 definite mechanisms for getting wheel lift.
Mechanical jacking
Dynamic jacking (lateral loading on seat etcā€¦)
These are counterintuitive in regards to setup, and I feel this is where people get confused.
And the term ā€œgripped upā€ only refers to binding of the rear axle on exit.
I try and isolate the 2 modes and ascertain what I have on the day. but that being said the wet is a good example of how you can go either extremes and get a fast kart. Bugger, just confused the situation again.

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