Track Tac

Early fire tire vs late firing tires

1fasttiller

1fasttiller

Member
Wanted to get some opinions from you experts on this subject as its what killed us this past weekend at our first World 100 in Jasper! My son was running Jr2 with 24 other bad fast kids and came from 13th where we qualified, all the way to 5th in the first main but if it weren't for many cautions, he wouldn't have been able to maintain that spot as the tires were wicked fast for about 4-5 laps then fell off fast. This seemed to be the issue for us all weekend. If a race stayed green like the final Pro Race on Saturday did we slipped back fast after he got about 5 laps in. We had ran all the way up to 5th-6th in the first few laps so the kart had speed but this race stayed green longer and he steadily lost positions ending up 10th for the big money.

I had multiple sets of Maxxis with different chemicals inside and out. Tires feathered up and looked great when he came off the track telling me they weren't too soft?

Is this all chemical choice or something to do with setup???
 
racing promotor said:
You say tires feathered up and looked great, it can't be both ?
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I always look for a light feathering or graining across the tires to let me know I was getting in the track and the tire working. Is that not correct? The one pair I tried earlier that day were much harder and didn’t even wear the ink stamp off them.
 
1fasttiller said:
I always look for a light feathering or graining across the tires to let me know I was getting in the track and the tire working. Is that not correct? The one pair I tried earlier that day were much harder and didn’t even wear the ink stamp off them.
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Light feathering & grainIng across the tire the tire is to soft, you just answered your original question, keep in mind the chemical is part of the reason why as well, a Maxxis that is working will only show that on the edge maybe 1/2 " wide max.
 
How were the tires prepared internally and how many weeks out were they? That’s be my first question if he was good at the beginning of the race then fell off on long runs.....
 
Gee, if only we had some tire temp data to consider, or how about the durometers don't matter crowd?
No, I'm just joking...not to derail the conversation...
Obviously hardness and temperature do matter. Tires wear as a way to help cool themselves. Excess heat causes excess wear. Too soft also cause the tire to wear prematurely.
I like to see some "graining" in a tire after it was ran hard, but you should not see any feathering.
It sure sounds like you were too soft on duro, the tire built up some heat a few laps into a run, and experienced wear (feathering in your case.)
Now, Earl was there, and he said that the track had low bite. Low bite doesn't typically build much heat or wear tires. That makes me think that you were too aggressive on your internal or possibly that your tires were too fresh. I am leaning toward the prep and amount rolled being too aggressive.
Without giving your whole tire program away, I'm curious what duro you were at and how many ounces of what, (& how many weeks ago,) was rolled in your tires, and then what you did externally to them.

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Well, we went with our team and had several sets, all with different amounts internally and different chemicals wiped outside.

This issue seemed to happen to us on two separate sets in both Features Saturday.

Set one used in feature one were originally rolled with Matt Connell inside approx 6 months ago and were ran in 2 features at another track with wins. We refreshed the roll on these about a month ago with some Insanity inside. These were punching 54-55. Only external wipes that day with HLII. He was much faster on this set. Actually placed 5th in this race but if it had stayed green long it would have been worse.

Set two used in feature two (pro) were a fresh set from a team member, just rolled within 2 weeks with insanity aggressive then heavy wipes of Krug clear on the outside while rolling in the hot box just before the feature. It was in the mid-low 60's that night and the dew was heavy so we had these punching 50 when they were bolted on. This set actually locked him down more than anything.

The track was definitely Dark BLACK with a beautiful groove but it was a prep groove I believe and not really rubbered up. I know we've got a LOT to learn on tires for this type of show!

Thank you all for you input though! appreciate the responses!

Does anyone know who Austin Yarbrough has doing his tires? The guy is a wheelman for sure!
 
1fasttiller said:
Well, we went with our team and had several sets, all with different amounts internally and different chemicals wiped outside.

This issue seemed to happen to us on two separate sets in both Features Saturday.

Set one used in feature one were originally rolled with Matt Connell inside approx 6 months ago and were ran in 2 features at another track with wins. We refreshed the roll on these about a month ago with some Insanity inside. These were punching 54-55. Only external wipes that day with HLII. He was much faster on this set. Actually placed 5th in this race but if it had stayed green long it would have been worse.

Set two used in feature two (pro) were a fresh set from a team member, just rolled within 2 weeks with insanity aggressive then heavy wipes of Krug clear on the outside while rolling in the hot box just before the feature. It was in the mid-low 60's that night and the dew was heavy so we had these punching 50 when they were bolted on. This set actually locked him down more than anything.

The track was definitely Dark BLACK with a beautiful groove but it was a prep groove I believe and not really rubbered up. I know we've got a LOT to learn on tires for this type of show!

Thank you all for you input though! appreciate the responses!

Does anyone know who Austin Yarbrough has doing his tires? The guy is a wheelman for sure!
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Most likely the Re Roll got ya, and without the Re Roll probably would of been better with little more aggressive than hot lap II wiped outside
 
This has been a great thread to read and stay out of, butt I have a question.

Remembering way back for compound and grip per what I remember JWD explained it's... (proly wrong statement but it's really a question)

... so per the feathering you brought the softness down too far to match the abrasiveness of the track.
If your tires would have come off looking right without the feathering all across then it would have been a task to match air pressure to the grip offered by the track.

... sure it's normal to chemically get more grip but when you have physical signs the grip your going after via softening starts to damage the tire you've gone too far. ... and if you were far enough then it's fine tune to match the grip offered by the track with air pressure. ??????

hope my questions/statements are correct and appropriate. ????????????????????


edit: only thought left per JWD's three rules is did your internal prepping also soften the sidewalls when they did not need any softening?

edit again: and that leads me to another question or two.
Did you do anything while internally prepping like bb's or tape to keep prep off the sidewalls?
 
paulkish said:
This has been a great thread to read and stay out of, butt I have a question.

Remembering way back for compound and grip per what I remember JWD explained it's... (proly wrong statement but it's really a question)

... so per the feathering you brought the softness down too far to match the abrasiveness of the track.
If your tires would have come off looking right without the feathering all across then it would have been a task to match air pressure to the grip offered by the track.

... sure it's normal to chemically get more grip but when you have physical signs the grip your going after via softening starts to damage the tire you've gone too far. ... and if you were far enough then it's fine tune to match the grip offered by the track with air pressure. ??????

hope my questions/statements are correct and appropriate. ????????????????????


edit: only thought left per JWD's three rules is did your internal prepping also soften the sidewalls when they did not need any softening?

edit again: and that leads me to another question or two.
Did you do anything while internally prepping like bb's or tape to keep prep off the sidewalls?
Click to expand...
We didn't use much internal in tires for this race, knowing the track and the amount of karts that would be on it. The most I used was 60cc in the rights so I don't think much if any got on the sidewalls and no, we don't use BB's or anything like that. Just a super slow tire roller which I think helps keep anything off the sidewalls.

I do think Had I gone up in air, we could have been better, especially on the second feature where we got locked down. The tires for that race had plenty of bite! But it was late and chilly, I misread the track big time!
 
1fasttiller said:
We didn't use much internal in tires for this race, knowing the track and the amount of karts that would be on it. The most I used was 60cc in the rights so I don't think much if any got on the sidewalls and no, we don't use BB's or anything like that. Just a super slow tire roller which I think helps keep anything off the sidewalls.

I do think Had I gone up in air, we could have been better, especially on the second feature where we got locked down. The tires for that race had plenty of bite! But it was late and chilly, I misread the track big time!
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provided you were locked down because of over prepped to soft, going up in air would have only built heat quicker which means most likely fell off quicker as well.
 
racing promotor said:
provided you were locked down because of over prepped to soft, going up in air would have only built heat quicker which means most likely fell off quicker as well.
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Please explain how this makes any sense at all. Given they were locked down, increasing air would lower the contact patch, lowering the rolling resistance, therefore lowering friction, and thus creating less heat. This is my understanding of how increasing air works, please explain how I'm wrong here, I am seriously asking because it doesnt make sense the other way.
 
Another question and then I hope i'm done.

I think all of us understand how moisture causes pressure buildup and that is the main reason to use dry nitrogen in your race tires.

And what follows is just ramblings... might it be possible to read and know the water content of the air you have inside your tires to control how quickly they build heat and pressure because of the moisture content?

... i'll go crawl back under my rock and listen
 
racing promotor said:
provided you were locked down because of over prepped to soft, going up in air would have only built heat quicker which means most likely fell off quicker as well.
Click to expand...
So I'm incorrect in thinking that tires with too much grip (bite) would work better with higher air? Wouldn't the higher air cause the soft tire to have a higher and harder sidewall? Wouldn't it take some of the excess grip out? Higher air increases the spring rate of the tire so it takes away grip though?
 
paulkish said:
Another question and then I hope i'm done.

I think all of us understand how moisture causes pressure buildup and that is the main reason to use dry nitrogen in your race tires.

And what follows is just ramblings... might it be possible to read and know the water content of the air you have inside your tires to control how quickly they build heat and pressure because of the moisture content?

... i'll go crawl back under my rock and listen
Click to expand...
Paul, I can certainly see moisture causing issues on asphalt racing in big cars but I don't think these karts (especially kids classes) build enough heat for the moisture to be a factor. Now the crazy prep chemicals we use internally with very high VOC's I'm sure are contributing to the pressure gain/drops!
 
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