Undriveable kart: tyre, track or chassis issue?

Good morning everyone,

I’ll briefly explain my problem: I have a race tomorrow, Iame X30 category, and usually on Saturday (today) I go to track tests with the other riders. Unfortunately today I have a family commitment and I had to go yesterday.

The day was disastrous: on this track, which I know very well, my times are around 40.3 / 40.8; in the March race I qualified in 40.0, the pole time was 39.5. The asphalt has been redone a year ago, it is quite smooth, so in the heat you lose some grip and in the hot months (here in Italy we are around 36 ° these days) the times get up about 5-8 tenths.

As mentioned, I went to test yesterday, the track was totally empty except for two bikes, and for the whole day the kart was undriveable at the rear: the sliding was continuous, the times were very high (best time 41.9 but the average was 42.5, the afternoon even 43) and the tires seemed burnt.

We tried everything: changed 3 axles, heights, track widths, tires, but the times remained the same. My mechanic says not to worry because the track was so smooth and not very rubbery, so the scorching heat burned the tires, which got hot but didn’t grip the asphalt as there was no rubber. In fact, when I enter the box the tires were incandescent but the hand did not stick to them, they seemed vitrified.

In your experience, is it possible that in particular conditions like these on such a short track, times can increase by 2.5 seconds per lap? I would like to have some reassurance from you that are more experienced, but at the same time if you think it is impossible I start to fear that I have a problem with the chassis. At the sight it looks perfect, since the last race (in which I was fast) I haven’t used it anymore so I don’t see how it can be damaged, but everything can be. The engine also has all the correct parameters.

It’s impossible to say exactly how much time could be lost due to poor track conditions, but certainly if the surface is newer and doesn’t have any grip except when it is driven on, there will a noticeable difference in grip on an empty Thursday or Friday than a busy day.

Our local track can be 1 sec if pretty easily on a week day and the surface there is well-worn in. I wouldn’t be surprised to see 2 sec of track evolution on a race weekend on certain surfaces.

1 Like

Last weekend we had a race and the track went through major evolution. Granted I didn’t fight setup like you did. But from Thursday practice to qualifying it was around 1.6 seconds.

Sounds like you have lots of laps there. Toss your baseline setup in and go from there.

Was there rain recently? I’ve felt 1s+ difference between green track and rubbered. I was worried but the other guys times were off too.

No rain recently but I had a very strange sensation from the very first lap, seems like I was “floating” on the asphalt. The steering wheel was very light and I could’t feel the wheight of the kart in my hands and the contact between tires and asphalt.

I was really convinced to have some issues, like wheels not fastened well to the axle or a problematic tire. The rear tires was screaming very heavy while turning, also at slow speed. Never felt anything like this! This Is why I’m little bit afraid for tomorrow

Sounds like you just went to a cold track. You have to remember with track conditions, it’s not just the temperature of the air that affects grip levels. If you were the only person on track, that’s way different than a raceday or even a busy practice day. Every kart that goes on track adds heat to the track surface and cleans off the dust and fine dirt that settles on the track when it’s cold. This is not an insignificant change in both the laptimes but also the feel of the kart.

Earlier this year we were running in Orlando and had to go through the LCQ. Our LCQ was the first out after the lunch break, and even the 30 minutes between sessions was a noticeable difference. Orlando is an extreme example of that case, but I’d wager that you’re experiencing the same thing.

1 Like