Tire duro

intimidator3

New member
Why should the left rear be harder? Left front softer? (Than rights)....just asking because I am having trouble keeping my left rear harder than rights....my rights keep hardening up at a faster rate. What effects does this have on my handling?
 
Why should the left rear be harder? Left front softer? (Than rights)....just asking because I am having trouble keeping my left rear harder than rights....my rights keep hardening up at a faster rate. What effects does this have on my handling?

Don't think that LR being harder has as much effect on these newer chassis, theory on the older stuff was so LR would slip some to free up grip a little so it would not tend to drive the kart straight in the middle causing a push, LF is the first tire to grip more to turn so being little softer just assures that.

Some guy's will argue a kart cannot push off the LR, I've always begged to differ on the older chassis.
 
a kart can very much push off lr

By my definition of how a staggered solid axle work and general BS, yes you can push coming off with too much LR.

Quoting me and the way I see things, Accelerating coming off the corner the RR must out accelerate the LR or be forced to turn by the fronts or if the fronts can force the RR to turn because of lack of acceleration from the RR, you'll push coming off the corner.

Yes I can see traveling across the track from inside to out accelerating coming off, but when ya kiss the wall doing it, yer pushing. That leads into Rule #1. ya can't turn and accelerate coming off the corner while going up hill, without pushing.

Reason for the rule, doing so dumps everything on the LR, causing it to drive you straight. Now if you got a lot of hp and you can dump on the LR and sort of ride slowly up the hill the entire length of the back or front stretch, beating those rim riding to the entry of the next end of the track. You'll see Sprints, late models and big blocks doing it and wonder how the heck they get shot out of a cannon like that. It's not about them finding magical grip down low, it's about dumping on the LR and go!

maybe, ????????????


yep, maybe??????
 
I shouldn't mess with this one. If you've got a lot of stagger, and a soft LR, it's going to slow you down on the straights. A harder LR makes it easier to slide, which it is, on the straights. If the stagger is not right for the turns, and the left rear is on the ground, if it's harder, it will slide better there too. Just a couple of thoughts.
 
I shouldn't mess with this one. If you've got a lot of stagger, and a soft LR, it's going to slow you down on the straights. A harder LR makes it easier to slide, which it is, on the straights. If the stagger is not right for the turns, and the left rear is on the ground, if it's harder, it will slide better there too. Just a couple of thoughts.

Yes It Could. ... :)

But what if its the RR you slide instead? Then how would things have to work?

___________________

edit: Morning coffee and more on it, probably wrong, but maybe ok.

Yes stagger is matched to the track. But your matching how what ever stagger your using, will function with the track. Yes matching stagger to the track can be faster, if it more closely matches a calculated radius. The goal in general is to split the work between both rear tires, having each work in specific ways, so you can decelerate, roll the corner and accelerate, through out a changing radius turn.

If a turn is an arc through out it's distance, then yes match up your stagger to the radius and go. I then Al, will 100% agree with you, about what you presented in post #5.

Maybe the following will help explain(assuming I'm correct on the thought process). ... :)

I wrote with difficulty: "Yes matching stagger to the track can be faster, if it more closely matches a calculated radius."

Please notice the words "can be faster". To help make it more understandable it might help if I relate it to Occam's razor. I think I can do it by saying what many on here will read as correct. I will say, too different amounts of stagger can be equally fast. If I then apply Occam's razor to it, the stagger which most closely matches the radius of a turn, will cut off the most items complicating the issue.

How'd I do Al? I keep waiting for you to say the light bulb went off and you now can see the possibility of control, via slipping and applying the RR. Slip either and you can get around the track, the difference is in the efficiency of getting around the track.

... and maybe because this is all IMHO and ain't necessarily right anyway. ... :)
 
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Why should the left rear be harder? Left front softer? (Than rights)....just asking because I am having trouble keeping my left rear harder than rights....my rights keep hardening up at a faster rate. What effects does this have on my handling?

intimidator3, ditto from me on what racing promotor, gave you to think about for a why of it.

_________________________________

You asked: "my rights keep hardening up at a faster rate. What effects does this have on my handling?"

Three different people have replied it may lead to a push coming off. I threw my two cents in saying the reason for the push is if the RR gets hard and looses grip, it cannot do it's job keeping up with and rolling ahead of the LR.
________________________

From your question and the responses, I'm going to have to ask, because I like questions so much ... :), Do you experience a push coming off, especially later on in the race? If you say yes, then maybe you have an answer to the why.

If you say no and the information you got as an answer is still correct, then even though your right side tires are getting harder, they still have enough grip left in them to be able to roll faster then the LR when needed. Maybe along with your right side tires getting harder, the track is also gaining bite or grip, keeping all ok. Maybe in the grove where the kart run, it's mainly the part of the track where the right side tires roll, that gains the most bite or grip?

Weather or not it's ok, all depends on where your tires were and the track was grip wise. They may change perfectly for you during the race day, but you then may need to change the tires back to where you need them starting out, between race days.

I know very little about prepping tires, the last sentence just seemed to flow and fit in. Weather or not it's possible to adjust your tires, like I suspect you may need to do, will have to be answered by someone who knows prep.

Thanks for reading.

paul
 
"I am having trouble keeping my left rear harder than rights....my rights keep hardening up at a faster rate."

I don't remember ever reading about the rights hardening up faster then the lefts, on here before. Is it common? I guessed at maybe the track coming in and changing more towards there the outside tires run, but it was just a guess on how it may effect tires getting harder.

If the rights are used more, then I would expect them to wear more or feather more, which has often been asked about on here. I think the general answer about feathering is usually, if it ain't real bad and you win or run up front don't worry about it. But we have many tire experts on here, don't we? Why would they get harder? Is it a false duro reading and they need to be scuffed or something before taking into consideration hardness?

Joey(JWD) many years ago on here explained tire needs and use for how hard or soft the surface is, air pressure and sidewall stiffness. He associated each with specific track conditions. The hardness of the surface of the tire is one of the three. How is it controlled chemically. Would you tread out side tires is a specific way, knowing they will move from soft towards hard faster then the left side tires? And what do you do between race days to put them back to an again usable condition?

The original poster got some info about what problems he might expect, but nothing so far from all the tire experts out there about how to deal with the problem chemically. Could how you treat inside the tire rather then outside the tire be what needs to be changed? Maybe inside treatment a little more to outside tires, then inside tires?

Is this maybe getting into something those who treat tires, don't want to talk about? Or maybe you experts out there don't have a clue how to adjust the tires, to help the original poster? I know I don't have a clue what to suggest. ... :)
 
I hope you don't mind my butting in and asking for more about it, intimidator3? I hope I'm not hyjacking your question asking about tires. Or are we doing ok so far?

edit: I just looked at the "Tire" section on here and you asked the exact same question there. I guess with it being asked there, your only interest here is about what problems others think loosing grip at the outside tires might cause.

Did you get answers here, you expected to get about the push? We can learn too from your question AND your follow up.
 
Why should the left rear be harder? Left front softer? (Than rights)....just asking because I am having trouble keeping my left rear harder than rights....my rights keep hardening up at a faster rate. What effects does this have on my handling?

Why are they doing this?
But to answer the original question, if its a newer kart, the LR and the rights should be close, if not a bit softer for the LR.
 
Uggh....

A push can not be caused by the LR. PERIOD!!!

Why?

Because push is a rotation condition and the LR tire has nothing to do with rotation. It's a drive tire.

A push occurs because either the RF is underloaded and can't rotate the kart. This is a too free condition and the most likely issue with new karts. The weight solution to this is add cross.

Or, the RF is overloaded and won't rotate the kart. This is a too tight condition and the most likely issue with older karts. The weight solution to this is add left side. In very old karts the weight solution is remove noseweight.

Notice the weight solution in everyone of the push conditions adds weight to the LR. Therefore the LR can not be the cause of the push.

Now you could possibly have major lack of grip issues where the cross adjustment simply isn't enough and you additionally have to add right side weight and or stagger. But again that has NOTHING to do with the LR tire.
 
Uggh....

A push can not be caused by the LR. PERIOD!!!

Why?
then why do they put so much caster in Sprint karts? Answer; because if you don't get that inside rear tire off the ground, the kart will push.

Why do we have stagger? Answer; so that both rear tires can be rolling around the turn, versus having one sliding and one rolling. The closer both rear tires come to the same circumference, (and the smaller the radius of the turn the more this is true) the more the kart will tend to push. Of course this is only true if the LR is on the ground. And, if it's on the ground, and the stagger is correct for the turn, you have more side bite. A sliding tire has less traction than a rolling tire.
 
then why do they put so much caster in Sprint karts? Answer; because if you don't get that inside rear tire off the ground, the kart will push.

Why do we have stagger? Answer; so that both rear tires can be rolling around the turn, versus having one sliding and one rolling. The closer both rear tires come to the same circumference, (and the smaller the radius of the turn the more this is true) the more the kart will tend to push. Of course this is only true if the LR is on the ground. And, if it's on the ground, and the stagger is correct for the turn, you have more side bite. A sliding tire has less traction than a rolling tire.

I have to agree with Paul, excellent reply Al. wish you could see the difference between this reply and your normal reply, now your debating not degrading.
 
Well. I haven't posted in a while and didnt realize how many replies this topic got. Sorry about not following up sooner. I have solved the push by changing weight. 10 pds from back of seat to the nose. The kart was fast even though my rights are about 5 to 7 points harder than my left rear. My left rear showed signs of wearing/feathering though. I just wonder if I am leaving speed on the table with my left rear being softer and feathering?
 
Well. I haven't posted in a while and didnt realize how many replies this topic got. Sorry about not following up sooner. I have solved the push by changing weight. 10 pds from back of seat to the nose. The kart was fast even though my rights are about 5 to 7 points harder than my left rear. My left rear showed signs of wearing/feathering though. I just wonder if I am leaving speed on the table with my left rear being softer and feathering?

Did you win? ... :)
 
Nope....ran 3rd and 4th. The 2nd and third place where not that much faster than me...probably just got outdrove. Kart was pretty good. Got beat slightly down the straights. Probably needed to go down a gear. Alan Garner was the winner. I am new to karting but I hear he is really good. Definitely diddnt have the speed he had though.
 
Nope....ran 3rd and 4th. The 2nd and third place where not that much faster than me...probably just got outdrove. Kart was pretty good. Got beat slightly down the straights. Probably needed to go down a gear. Alan Garner was the winner. I am new to karting but I hear he is really good. Definitely diddnt have the speed he had though.
Did this happen to be at Buffalo monday? Gardner was definitely fast.
 
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