Kart tyres are many and diverse, both by brand and by type. In official competitions they’re imposed by the rules; but when you’re driving for fun … you’re free to choose. But a doubt plagues enthusiasts: which tyre should they buy? Harder ones that last longer, but don’t perform as well? Or softer ones with better grip, but a shorter life? And how long do they actually last? Also: how does their performance change from one lap to the next? How much wear do they undergo?
We went to the track to get some answers.
Testing the life and performance of the Vega Whites
With a long run of over 100 km, divided into 10-lap sessions.
Test 1: 10 laps with new tyres
Test 2: Laps 11-20
Test 3: Laps 21-30
Test 4: Laps 31-40
Test 5: Laps 41-50
Test 6: Laps 51-60
Test 7: Laps 61-70
At the Adria Karting Raceway in Adria (Italy)
Well-maintained and smooth asphalt, with good (but not excellent) grip following the race held there on the weekend prior to the test
It’s well-known throughout motorsports that the performance of new tyres during the first few laps generally can’t be replicated later on. On account of this, for the first 10 laps of the test, we decide to simulate a session of qualifying heats. Initially we keep the pressure of the Vega Whites lower with the goal of reaching the recommended pressure levels during the test: 0.78-0.82 bar. In setting the pressure levels we also keep in mind the greater heating of the tyres in traction and of those on the outside, in this case those on the left since the Adria circuit runs clockwise.
Once out on the track, the tyres immediately show good grip. Lap times are good from the start, just over 53 seconds, then falling on two occasions to 52.98 and 52.96 seconds. A time of 52.62 seconds was registered, however, on the 8th lap: the best time of the session. At the break, pressure measurements indicate the same value for all 4 tyres: 0.8 bar. Perfect!
The treads indicate optimal tyre behaviour, with just a hint of excess slippage from the outside rear tyre, the one put under the greatest stress. This is visible on the inner part of the tread, in an area roughly 3-4 cm wide. This can derive from many factors: an insufficiently-rubbered track causing the kart to slip a little too much, an excessively soft axle, an overloaded front axle … Still, the tyres tell us that the setup is correct, with some small issues in the rear.
After the first session, grip is still optimal and steering is still easily controllable, even when pushed to the limit. Times are decent, but there’s no chance of repeating the exploit of the first session. The best time comes on the second timed lap (the third if you count the opening lap) at 53.92 seconds. The fourth lap is still under 54 seconds, but from the fifth lap on things settle around 54.2 seconds. Back in the pit, tyre pressure has changed little compared to the first session, though it is a little less “perfect.”
We’ve now completed a good number of laps: it’s as if we were more or less halfway through the race and had already completed the qualifying heats (about 10 minutes). The tyres are pretty stable and we continue recording roughly the same times as the previous sessions (around 54.2 seconds), the best lap being the third at 54.16 seconds. That means we’re now 540 milliseconds from the fastest time in qualifying, without ever changing the amount of mix in the tank at the beginning of each session.
A problem with the air filter forces us to return to the pit more slowly. This can also be seen from the tread’s very irregular surface, which shows how the hot rubber stuck to the asphalt in the slower last two laps. Tyre pressure has fallen as well, highlighting how a couple of slower laps can completely change the tyre situation on returning to the pit.
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