Hi, my son has been racing for several years in different categories. We’re currently running 2025 Rotax Senior and Junior engines. In the most recent rounds, we’ve been experiencing what I believe are tire pressure issues. We’re using LeCont LH03 tires.
The main problem we’re seeing is that when we mount a new set of tires, lap times either get worse or stay the same compared to worn tires. The kart also feels like it’s sticking too much to the track, which leads me to suspect a tire pressure issue.
That said, I’m open to any advice—not just on tire pressures but also on potential OTK chassis setup changes (alignment or anything else) that might help specifically when going out for qualifying. Our qualifying sessions are usually 5 minutes long.
I hope the problem is clear, and I’d really appreciate any guidance, tips, or explanations. Thanks in advance!
As you say tyre pressure, compare the qually session with a normal pratise session and see When the best laptime normally is, i would not be surprised if its past the 5 min mark.
Setup of kart on used vs new rubber, if the old tyres are very old there Can be a significant difference In setup.
Driver not used to run on new rubber, its simply a qustion of not being able to use the full potential of new rubber.
Generally its highly adviseble to use a new set In one of the last practise sessions, we often (if money is for it) do it the last practise session before qually and dont run longer then the qually session is, with these short 5-6 min sessions it Can be hard to get everything right, but In reallity you have 2-4 laps where the tyres are at their best, if the time is not within lap 2-4 i will claim you not getting the best time possible.