Wall Thickness

We were just wondering what the wall thickness is on different tubes sizes. Is the wall thickness on a tube that is 1 1/4" thicker than the wall thickness on a tube that is 1 3/8"?
 
Wall thickness, will depend on several things , in some venues like ikf and wka call out a minimum wall thickness. the euro karts used in the sprint programs need to meet a minimum requirement while dirt/speedway racing allow a margin of excepted practice . meaning, if its to thick or two thin it wont handle right. there are some going down to .0625 then adding frame torsion bars and stifners . others prefer to stay around .083 to .o95 for consistency and performance . is there only one correct answer ?
no
 
We were just wondering what the wall thickness is on different tubes sizes. Is the wall thickness on a tube that is 1 1/4" thicker than the wall thickness on a tube that is 1 3/8"?
the only thing I can think of is "maybe". The stiffness of a tube is a square function of the diameter, and linear with an increase in wall thickness. The diameter and wall thickness of the tubing is determined by what the builder hopes to achieve in handling.
 
We were just wondering what the wall thickness is on different tubes sizes. Is the wall thickness on a tube that is 1 1/4" thicker than the wall thickness on a tube that is 1 3/8"?

That can and will depend on the manufacturer. Some will start at, lets just say back bumper as an example, .083" and at the waist of the kart it may be .095", and then at the front may be back to .083" again.
Theyre not always the same thickness all the way through the rails, and sometimes they are.
Theres more to designing a chassis than wall thickness and diameter.
 
There is a device that can measure the thickness of a tube. I've used it. Just a little handheld electronic device. You put it on the tube, hit a button and it tells you the thickness. Pretty accurate to. Probably too expensive for use in karting.
 
There are many different wall thickness available for any size tubing. In essence you can order almost anything you want, find an outfit like , "Tube Sales", they will have lists of available sizes. That tool is used by race car engine builders that bore engine cylinders, they need to know how much they can bore and it is also used to find core shifts that happen in casting, that might make a block un-usable.
 
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I think it would be nice if some chassis manufactures would get on here about it. Your question is one I've had for years and there's a lot of secret rumor's about answers. You'll also get the, well different tubing thickness is used at different places on the kart. Here are my rumored thoughts on it. I expect what I say will be shot down by those who really know. I'm saying up front, I don't know and this is what I remember being told years ago.

In general most karts use to be made with 1 1/4 .095 tubing. Years ago someone tried 1 3/8 .083 and found out the 1 3/8 was lighter and even a little stiffer. I think?

... I remember years ago BA (before armor)(proabaly wrong cause I'm old and get 1 1/4 and 1 3/8 mixed up) being shown a new 1 3/8 chassis. We put our 1 1/4 next to it and the 1 1/4 looked small because the new kart had .083 tubing. Then I was told to lift up the front of the 1 3/8 and then lift up the front of the 1 1/4. To my suprise(If i'm remembering correctly) the BIG 1 3/8 kart was lighter.

Well IMHO, if your selling karts which is going to out sell the other? The BIG impressive looking... lighter kart, or the smaller looking ... heavy kart?

And that's just the way I remember it and it could be all wrong. ... :(
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Also around the same time karts were switching to plate front ends. The initial theory which proved not to work in practice, was to get zero flex at the front end and be able to fine tune adjustments. The 1 3/8 tube worked well with the new plate theory. And original thoughts on the RF being stiff made more manufactures try 1 3/8. Turned out customers preferred the 1 3/8 too, so there was no reason to go back. And eventially the RF chassis area went back to pre plate design, flex was back in at the RF and it brings us up to today.

Just too add more into it because I know getting into chassis, your mind goes to all kind of questions. And I like to tease your mind and mine to think about how stuff works.

IMHO, there are two basic flexes built in at the RF area of your chassis. The first is called pre-load and the second hasn't a name I know about. You'll eventually get into thinking about caster, kpi and camber. You'll also hear about load being transferred to the RF. Wouldn't it be cool if more load to the RF would automatically change RF adjustments as needed? That's where the second type of flex at the RF corner come into play. Good hunting about how stuff works on here. Ask, Ask, Ask. Take everything you hear with a grain of salt, but store away everything you hear. The only way to know for sure about something is try it on the track. And never leave behind anything you hear that might be far out there, it might just fit in somewhere, someday.


... and go buy Ltg's books you'll find him on here. He has a basic get into it book and a more in-depth one. I've never bought either, because I'm too cheap and too lazy. But I have read and digested most every free article he's put out there. Only take what I write as a fun thing, go to Todd's books for the real skinny.
 
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There are many different wall thickness available for any size tubing. In essence you can order almost anything you want, find an outfit like , "Tube Sales", they will have lists of available sizes. That tool is used by race car engine builders that bore engine cylinders, they need to know how much they can bore and it is also used to find core shifts that happen in casting, that might make a block un-usable.

Hi Jack, could you post a url to the site your referring too?
 
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