Chassis flex

I believe he and I are referring to the left and right rear tires being closer together opposed to being wide track tires pushed away from the center line of the kart. I have said this before, i am a firm believer if you calculate the perfect stagger to get the axle to follow the path of the corner you have too much stagger. Stagger should be a compromise of getting the rear end around the corner and keeping you speed up in the straits. My opinion is a lot of "The Tire Game" is people not utilizing adjustments to the chassis.
 
It goes without saying, stagger helps in the corners and is an impediment down the straight.

We need to find a balance, how much does it help in the turns, how much does it hurt in the straights. A perfect Circle would be no problem as far stagger is concerned, unfortunately, most tracks have those pesky straightaways to contend with. The longer they are the peskier they are.
 
Quick note on that dual rail 2019 kart aka the Phantom Duece. That double rail is helpful in stiffening the chassis and creating more role speed than even the new scythe. It takes an expert to get the setup right but if it is and the tires are spot on they are bad fast karts. Just out of the norm for LTO karts. It's like the seraph. Bad fast if done right, total turd if wrong. The tire game is where a lot of speed can be found if done right. Most people can't do it right and get the setup perfect and that's why people hate on it.
 
the idea of the chases is to be flexible enough to keep all four tires on the ground. I have seen many a kart on the grid with the left front spinning in the air because of the demand for such high cross. I can't see how making the chassis stiffer and stiffer is better unless the idea is to have the kart tri cycle down the strait maybe that's the next big thing. I t thought my 95 shadow kart with the small diameter tubing was faster than my banshee with the larger tubes. but that was back in the late 90s. don't know what it would do today. however if you wanted to make the kart stiffer there are ways that aren't as heavy as running dual rails. larger diameter tubing, thicker wall. or not have the chassis bottle neck as much. but then nobody would notice that so it wouldn't be different enough. because that chassis was abandoned so quickly and the fact I heard the factory boys are already on the new 2021 model im not sure the kart was as good as you think or why would they have gone back to the more conventional style. a lot of things are done just.to get you to buy a new kart . at least that's the story I'm sticking to.
 
Hey phantom does some odd things. I've seen very good results with both the Duece and the Scythe. Even the the guys at phantom will admit the Duece will produce more roll speed provided the setup and tires are spot on for the conditions. I don't think switching back to a already proven design was because the Duece was junk but to sell more with a more forgiving design. Hence why the triton was much easier to work with over the seraph. They have to look at it from a marketing stand point in what will sell the most chassis and if you cater to a wider crowd you'll make more money.

If you want to continue getting faster you have to innovate and there's nothing wrong with it. Some things will work and continue to be produced and others will also work but from a business standpoint can't be justified.
 
sorry if that design worked they would have stood by it. the 2020 model would have been an improvement of that design not a complete scrap. if it would have worked they would have been able to have the customer duplicate their results and if it was truly superior it would have dominated and the other kart manufactures would be scrambling to duplicate an ultra stiff chassis to compete with it. but that is not what happened and no one saying it was really innovative and had really good "roll"speed is going to change my mind. I think Phantom tries to release too many new models and are running out of ideas of how to twist up steel tubing and not make a chassis from 6 years ago by mistake. same deal with that ultramax excentric from an engineering standpoint the tubes running on top of the bearing hangers would make no difference to running them under but it looked different so it must be innovative. again if it was better it would be on the rival
 
I feel sometimes our Recon is a stiffer chassis than other manufacturers. This has caused us to have to run a few points softer tires. Not an expert it’s just what’s been working for us.
 
"chassis flex" a very elusive condition. In 1977 Richard Burton built a new kart called the Magnum. Built from 1 inch .083 chrome Molly. He gave me one. I raced it at the 1977 Atwater IKF Nationals. Qualified 3rd finish 2nd. It was a time of transition between the Good Years and the Bridgestone's. I was racing on Good Years. Later that year, at the Riverside Winter Nationals, I was in Richard Burton pits. Steve Vera was driving Richards kart. It was equipped with the new Bridgestone's, or maybe Dunlap's, not quite sure. In any case, in my observations, the cart was bouncing around like a tightly wound coil spring. I said to Richard "time for a new kart"! He scoffed at me. Quite vigorously, said that I was crazy. We all know who was proven right.
 
I don’t get why phantom said they had customers that wanted a stiffer chassis...they used to never be like this..building a new kart every year...every one I asked seems to like the scythe and haven’t heard anyone say anything about wanting a stiffer chassis besides what phantom said
 
Beyond inovation . the only way is too build it and try it in a real world setting .
The 35 was stiff or plenty stiff . The deuce was stiffer in a different way .
Neither were the most popular PRC chassis .
Stiff overall and stiff via the double seat rail .
 
Beyond inovation . the only way is too build it and try it in a real world setting .
The 35 was stiff or plenty stiff . The deuce was stiffer in a different way .
Neither were the most popular PRC chassis .
Stiff overall and stiff via the double seat rail .
I agree with you but they always did that in testing not sell it to customers and see if it works or not
 
the idea of the chases is to be flexible enough to keep all four tires on the ground. I have seen many a kart on the grid with the left front spinning in the air because of the demand for such high cross. I can't see how making the chassis stiffer and stiffer is better

There are three things going on with chassis stiffness at the RF corner which is what I think most have been thunkin and writing about.

The first is how flexing a LTO kart chassis waist to the RF changes how both located weight and dynamic transferring weight is projected towards and to the RF chassis area and to the RF tire.

The second is how flexing a LTO kart chassis waist to the RF changes the physical mechanical angles of the RF area of the chassis to in turn change either caster, camber, KPI, scrub radius or some or all of them.

The third and last thing flexing a LTO kart chassis waist to the RF changes is if it again in turn affects grip increasing or decreasing it what will follow will be either an increase or decrease in the amount of final weight on the RF tire.
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Next in my thunkin would be common everyday examples we all would understand or need to understand about why the three happen.
Here's a few quick and pertinent examples:

1. When LTO chassis first went to plate front ends the theory was doing so would allow for "Locking" in solid front end adjustments because the train of thought at that time was a need for accurate defined adjustments you could change and see solid results.
What happened is it didn't work as intended and the plates were then mounted back on stubs.
Doing so put flex back in and kept the needed easier adjusting of the front end.
The plates and heims are there today only because they make adjusting easier and not for speed.

2. The flexing allows for leveraging weight to the RF tire from a lower point via a longer lever.

3. It creates "Bump Steer" which we can use to our advantage changing RF chassis and tire angles in a positive way per RF corner chassis loading, instead of how usually Bump Steer negatively changing RF steering per bumps in the road.
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It is the reason why higher cross is generally easier to get fast then low cross.
If you bought into all that bull you'll also see and understand a reason why some tracks lend themselves to high cross and some more towards low cross.

Yes indoor racing lends itself to low cross because of how you need to control high grip.
Butt again if you bought into the bull above you will now see a second reason for low cross indoor racing under high grip conditions.

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Never had the guts to take a chance indoor racing because I was cheap and didn't want to tear stuff up racing indoors so I'll never be able to test the bull below out.

If my thunkin and writing is correct or even just close wouldn't stiffening the front end and waist help on an indoor high grip track?
Thunkin and writing now it made me reflect to the need for front sway bars on indoor midgets and I'm thunkin stiffening the
front and/or the waist will give some of the same dynamics a sway bar does.
And thunkin on the fallacy of the last statement trying to rationalize it into correctness, isn't the whole purpose of a sway bar to take lifting effort and move it across the front end allowing for a lower more over all lateral presentation of chassis weight to ultimately keep the LF down by redirecting dynamic weight?
Thunkin and writing I see the end result of stiffening the front and waist might do the same as a way of lowering and more laterally directing dynamic weight.

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I'm also thinking a result of dumping a ton of weight onto the LF indoor high grip racing is it does because of the additional load stiffen the front end.

... and this is again all IMHO and ain't necessairly right anyway. ... :)



ps.... yeah after writing this post and not reading thru it before posting I feel like I'm pretty darn close to correct on it. maybe??????? ... :)

thanks for reading
 
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If your theory is correct and you make a change you automatically have a correct reason for the change.

Butt your results will depend on a lot of stuff outside your theory including your driver. ... :)
 
Can someone explain what makes the older chassis like a nemesis flex more than the newer karts?
Thanks
If they do then it's either because they were made that way or flexing over time and use of an older kart softened the metal it's made from.

Why newer chassis were and are made stiffer "may be" because of what I offered in my last couple of posts.
What I was told by Phantom at Phantom a couple of years ago after the intentionally flexed right side of the Triton Jr via relocating the brake was now it's a matter of tires and tire prep more then a run of the mill chassis. They made the next chassis after the Triton to be just a regular and from your input probably a stiffer chassis so racers can rely on their already proven knowledge of tires and prepping them over chassis adjusting.

When I was there Harrill was in the back I could see him working with someone.
I had race pits to get too and was not able to hang around.
LOL, if he saw me it probably would have been enough reason to stay in the back. ... :)
I talked to a racer at the counter who was sort of thin not short and he explained to me it's now or back at that time it was more about tires then chassis.

Hope this offering of thunkin and writing helps answer your initial question riddler26, instead of the bull I wrote in my last couple of posts. ... :)
 
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My experience indoor is if you can keep the Lf down and the Left rear unloads or even lifts , your fine . When both lefts are up it's a problem .
 
I don’t get why phantom said they had customers that wanted a stiffer chassis...they used to never be like this..building a new kart every year...every one I asked seems to like the scythe and haven’t heard anyone say anything about wanting a stiffer chassis besides what phantom said
They are wanting a stiffer chassis due to how fresh tires are these days..... tires aren’t able to cure off the mold long enough like they use to be in the late 90’s into the 2000’s........ most chassis manufacturers are bolting in brand new sets each time they track test a prototype chassis to get the most accurate track reading to justify that a chassis will perform the best on that design....
 
There is a lot in the above statement . That makes a lot of sense .
Testing requires repeatability .
No way to design a new chassis to fit the local guy racing on second hand tires that are wore out .
 
Experience racing with high and low hp karts and now cars too, track conditions sometimes demand you to smack a tire hard down into the track trying to gain instant grip or ease it into the track. Read that sentence in mind of situations from high grip to low grip/slick.

Todays common karting situations which we usually think about and discuss are low hp situations and because of racer tire knowledge most always an over grip situation.

Because of that dirt LTO kart racing your usually going to need to 'ease' tires into the track sort of cuddling up to maximum grip instead of banging into it. IMHO stiffer chassis over all will lend directional weight travel laterally better then a softer chassis, making it easier to ease up to and cuddle up to the final amount of grip your going to use. and again maybe??????????????? ... :)

I write "maybe?????????" a lot because I usually spell 'necessiarely' wrong. ... :)
 
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