Home Forums General Karting Discussion Why do drivers sit so tall in sprint karts? Reply To: Why do drivers sit so tall in sprint karts?

#14501

Paul Kish
Participant

I shouldn’t have to explain but because you do not have a differential you “MUST” unload or slip the inside rear.

 

… before I go on, do we agree with that one point?

 

I can’t go on if that is not understood.

 

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I guess there is one other thing we have to agree on before I can convince you I’m correct.

 

If you take a tire, any tire and roll it do you agree it will want to roll straight?  (I know you can throw in a bunch of stuff that can make it want to not roll straight, but for all practical purposes, roll a tire and it will want to roll straight.

 

Can we agree on that?

 

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This next one may be a bit tougher for you to want to agree with.  But from what I read so far of your words you will not try to dodge it.

The tire which is rolling straight, don’t you have to add input to make it roll in a direction other then straight?

I think you will say yes.

And what if you added weight to it, won’t it take more input to make it roll in a direction other then straight?

I think you will… maybe reluctantly but I do think you will say yes.

 

I think you already know what happens if you make a tire roll in a direction other then straight.  Because there is no need to play 20 questions I’ll answer.  A slip angle will be created.  … not think about it…

To conserve energy and put the hp you have into going forward, would you want to turn one tire with a big slip angle or two with smaller slip angles?  It’s tough to say two ain’t it?  But you know you do feel two smaller slip angle will be easier to turn.  In fact they are.  Next I’m sure your going to want me to quote verse, rime and reason why two small slip angles will be easier to create then one large one.  … I can’t do that.  All I can do is say from all that I’ve ever seen LTO racing, unless you have gobs of hp able to take advantage of dumping weight on the outside rear, it’s faster to split the split angles.  If what your racing does have all the hp you need to put the hp to the outside rear and go, assuming the outside rear has all the grip you need, you will not agree with me.  But if you are at the limit of your hp, it’s faster to split the slip angles.  In LTO racing when you have the outside rear so heavily weighted it just wants to roll straight too much, we call it right rear tight or … Outside rear tight.

 

If your on a shifter you may not be able to see it.  But if your on a lower hp can or brigs, it will show itself to you.

 

… what follows is what’s left and what’s left is all about forces out on the track.  It’s how lowering the seat changes how you use forces to be able to free up the tires and split the slip angle.

I think I did ok explaining it, but time will tell.

 

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edit:  If your wondering why laydown seats can even be competitive, what I just explained above or at least tried to explain IS why.  Yes I understand the higher CG and how it helps leverage the chassis, but…  think about it… doesn’t the higher CG also create a longer lever and don’t longer levers work slower?  And then to make that longer lever work as needed, don’t you have to then round up extra effort to make the long lever work as FAST as needed?  Now… shorten the lever by dropping down the driver.  All of a sudden you also have a shorter lever to operate.  … hummmm… it’s a win win situation, ain’t it?

 

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thanks for the reply, been fun writing, I’ll look back in tomorrow am unless I head off to a track out east.

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