So when you say “torch” does that mean overheated, got to hot or overworked to much deflection or sliding? Maybe they are the same but Im trying to figure out what overheated would look like.
I’m not sure but I would imagine heat would be the only thing able to change the actual properties of the tire. Heat from excessive surface friction from sliding.
Was morning warm up on the same set of race tyres or a different set?
if it was a different set would back up the thoughts you hurt your race tyres and they never recovered
I came here to post what Andy did. I’ve never experienced anything like my tire troubles from this weekend before especially on a set with relatively low heat cycles for a “hard” tire. In practice I’ve run SH2s up to about 17-18 HC previously and not experienced anything like I did recently.
The kart was a nightmare to drive. It wouldn’t Jack and looked like it was flat sliding, but any changes to setup didn’t really help. I thought to chassis was broken but we couldn’t find any cracks. I was ready to drive the thing into the retention pond Sunday morning and leave it there. After putting new rubber it was magically better although it means I think I missed on setup having made so many changes chasing the issue. For reference the difference between my last morning warmup on the junk tires and qualifying on new rubber was a staggering 3.5 seconds a lap!
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Sounds exactly like my issue. Kart felt just evil. We joked it was “loose tight”. Like driving on ice. I also was looking for cracks in the frame or something because it literally felt broken.
I’ve heard from a couple more people now as well who have had similar experiences on the new Reds.
Updated opinion?One bad date doesn’t sink a relationship Derek. 
This particular set seems to have had a bad weekend, but now that I know that you can destroy these tires by overdriving or overheating them too much, I just have to keep an eye on that and maybe I’ll finally put batteries in my temp gun that’s dead in my toolbag.
Also, I had no issues like this for the entire season. I think part of the equation is the track layout at Trackhouse, which is mostly fast corners and mostly right-handers, so there is a lot of load going into the tires if you aren’t careful about managing them. Particularly turn 4 which is now a super-fast bowl that you cruise around at nearly max speed with all the grip that’s been laid down. That surely is torture for the left front. And given that I generally am hard on front tires, I think I probably need to adjust my driving style a bit to prevent that from happening in the future.
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Whoa. 3.5 SECONDS??? That is… something, wow.
I’m really curious to see if this would show up using a tire durometer. From the sounds of it though it seems like its not necessarily the tire surface thats causing the terribly different characteristics though. If it was just a harder tire it would just drive like it has less grip, but if the sidewall gets altered in some weird way… that’s a different story. @tjkoyen @Kutschca
In my club they race DD2 with MG SI tyres because it was faster than the SH and cheaper than the SM, but now some have noticed that the SH2 has the same performance
I can appreciate your wisdom and optimism. I know it was not your intent, but I have learned a ton about my set up and situation from your weekend. Over working tires, having too much grip, overheating tires, inconsistency on used tires. All things that I struggle with here locally on the SH2. I appreciate the write up and transparency!
Luckily for me, I am on the Hoosier R70 for the rest of the year. Its like a stop back to 2005 where hard tires and flat sliding set ups have a lovely relationship.
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Thats what I was wondering too, but I don’t think there is a way to tell if the structure of the tire is somehow damaged by overworking it.
Are the offending tires still around to durometer them?
Prodigy has mine. I would love to see a durometer comparison between a set of known “good” used tires and a similarly used set of “bad” tires.
Re sidewalls. I wonder if anyone has built the equivalent of a shock dyno, but for kart tires. You’d need something to measure laterally too since that’s crucial as well.
I think my case was extreme because the chassis just flat out wouldn’t work on the junk tires. It wasn’t like driving with low grip it was highly inconsistent on how and when it’d grip. Sometimes it wouldn’t turn in but then grip up mid-corner, other times it’d turn in, but then the rear would slide out at apex when loading up the side. It also didn’t help that we were on a configuration at NCMP using parts of the rental track so different asphalt surfaces and different levels of rubber across the turns which complicated things.
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Coincidentally that is exactly how I would describe my kart. I noted to my dad in the scale line post-session several times how unpredictable the kart was. I would go into turn 1 and be completely sideways one lap but understeering the next lap. I kept trying to adapt to how the kart was working but each lap it would feel different so I never felt comfortable all weekend. Like riding an angry bull.
I still have the tire but no durometer to test with. I actually wonder if there was damage to the sidewall structure somehow.
Whatever it may be I hope to never deal with it again as it was insanely frustrating.
I’m going to invest in a tire temperature rig over the winter. Whether that’s shelling out for the MyChron system or duct taping IR temp guns to my spindles, not sure yet.
I have a durometer somewhere…I"ll try to find it this weekend don’t throw those away yet we can measure and see if the data shows anything.
This thread is interesting to me because I experienced the same type tire “degradation”, for lack of a better term, at Stars Trackhouse.
Now, I’m usually a good 3/4 of second of the KA Master’s guys, but I found myself much closer at Trackhouse ibn the heat races. My qualifying got hosed by the rain a bit, but in the heats I was with .2 to .3 of the leaders, but I was turning what felt like all-out qualifying laps to get those times.
Sunday rolls around and all of a sudden I lose about .4sec/lap in the pre-final. Now everyone slowed down a bit, but not to that extreme. About three laps into the pre-final the kart just started to go away, it was still relatively balanced, but it was sliding a lot, a bit more so in the rear, but still fairly balanced.
Anyway, we made a few changes for the final hoping to gain some of the time back, but from lap one I could tell it wasn’t there, and it proceeded to get worse through the run. By the time it was over, I honestly thought a weld had to be coming apart somewhere. However, we looked it over and even took it to Tiago to check on the table, and it was dead-on.
I’m now starting to wonder if I just burned the tires up in those first two heats. Admittedly, I’m not experienced enough to feel comfortable pointing the finger at anything other than my own driving, so I had simply dismissed it as a case of just “running out of talent”, but now I’m starting to think it could have possibly been the tires.
We did flip tires on my kart after every session, for what that’s worth, and the tire wear looked good, but they felt lmore like tires that have 25+ heat cylcles on them as opposed to five.
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What tire pressures were you running? I was between 9-12 all weekend but because we battled the tires and a few other things I never felt like we nailed it. I have heard several other drivers were running a fair bit lower than that.