As anticipated last month we had already started a test with the new Le Cont CIK homologated tyres with new technical specifications. These tyres have now different oils that are more environmentally friendly, as ruled on a European level starting from January 1rst 2011. The big news is also that LeCont will be supplying for CIK the U18 World Championship with the LH08 CIK M and the Academy Trophy with the LH07 CIK H.
Structure of the tyres
Compared to the already tested LH 01, 02 and 03 LeCont tyres, the LH08 CIK M and the LH07 CIK H tyres for international racing differ in particular because of the varied hardness of the shoulder. A plastic insert is positioned in the shoulder to increase hardness, which will generate a more complex behaviour, where good setup is strongly needed. At the same time the tyre tread will be perfectly working and well in contact with the asphalt generating extremely good performance. So more potential performance, but a little more difficulty with these tyres compared to the LH 01, 02 and 03.
Also the tyre compounds of the M and L newly CIK homologated tyres differ from the ones of the LH previously tested. The M tyres we have tested have a tread hardness of 38,2 DIDC – IRHD for the front tyres and 37 for rear tyres. Service pressure value suggested is 0,5 bar.
Another aspect common to all LeCont tyres, which is a patented solution, is a special construction that eliminates any closing surface on the treat. This also means there is no real rotation verse and no possibility of the treat to open and come apart in the conjunction surface, because there is no conjunction! The only thing to consider is to keep the white label of the LeCont brand on the shoulder of the tyres always external. The two arrows of the badge are just part of the brand logo and do not indicate rotation verse.
First test on low grip track and cold temperature
As confirmed by LeCont company, the LH08 CIK M are tyres thought for international races, which means best use is on tracks with high grip and with rubber on the asphalt left by karts running. Also higher temperature helps these tyres performance.
Our first test, which had an early stop last month because of technical problems, gave us some disappointment on a very slippery track with no rubber on the asphalt and a very cold day, with temperature close to zero. Tyres seemed not to warm up and grip was constantly insufficient. Also when stopping after a set of laps, the tread of the tyres was not really warm and also was still hard.
Second test on track with good grip and warm temperature
Our second test, which we managed to bring well to its end, we made on a different track, the Viterbo International track, on a Saturday when many karts were running preparing for one of the first challenges of the KF and KZ, but also Rok and Super Rok championships. Day was warm with temperature around 18¡C.
Well it was incredible how the behaviour of the LeCont LH08 CIK M tyres changed completely. Grip was extremely good, kart was drivable and always performing well. At our first stop at the end of the session we looked at tyres treads and they showed a completely different look. The treads were really warm and the rubber was soft indicating tyres was working properly.
We proceeded with some more sessions and managed to find a good feeling with kart and tyres, decreasing our lap times from session to session. I even registered my best lap time at 46.40 sec, beating by more then 5 tenths my best obtained with Bridgestone tyres. In that situation though, it is correct to say that lap time of 46.94 sec was set on a day with few karts running and consequent low grip of the asphalt.
After the first session and my satisfying 46.40 sec lap time, we looked at the tyres and were quite pleased with the way the treads looked, especially on the rear tyres, and especially on rear external tyre, which suffers more wear and deterioration since it is the tyre on which the kart pushes most of the time. We had been running for around 45 minutes and wear was absolutely limited, which is the base to LeConts philosophy: good performing tyres, but always with constant and long lasting performance. This is something we had in fact criticized on Bridgestone tyres, which gave excellent performance, but lost some tenths after the first 20 laps, and quickly deteriorated loosing more then one second on lap times after the first 50 laps.
Even though wear was good we were not really convinced by the look of the treads of the front tyres. There was some disproportion in the wear of the internal part of the tyre, much greater, compared to the external part that was not really working.
We decided to adjust the setup of our Tony Kart EVR widening the front carriage of one and a half spacers (one big and one small spacer). This is quite a big change on front carriage, but we really wanted to check if this solution gave us a flatter front setup, which would in theory make front wheels treads work more evenly and horizontally on the asphalt. Also this would help in some fast curves such as the entrance to the long straight where the start is positioned and the curve at the end of this same straight, which is ran at very high speed just lifting partially the accelerator entering the curve and then accelerating again just after.
Well, the day was actually ending and the sun was lowering on the horizon, cool air coming quickly hitting the sweat on my skin and suite. I quickly went back on track with my new setup. Engine somehow was working a little better because of cool air. Also the sensation was of a more slippery trackbut also of a much better balanced chassis.
Precision along fast curves was well improved. Sliding of rear tyres was eventually much more uniform and predictable. Exiting curves was much smoother and effective. Lap times were soon good with 46.75 46.60 – 46.45 in laps 3, 4 and 5. Then in lap 6 tyres were warm enough for a new personal best on Viterbo track of 46.29 and finally on lap 8 my best overall of the day at 46.15 sec. I then decided to stop, quite happy I must say with the result. The choice made with the setup adjustment worked extremely well. Also the day had been a great day of testing and fun.
A check at the treads of the tyres confirmed my impression. It was incredible to see how now front tyres treads were extremely uniformly working. Wear was much better distributed from internal to external of the tyres. Actually the tyres seems even regenerated by my last session and showed they could surely go on many and many more laps.
We had finally ran more or less 1 hour and 30 minutes (about 120 laps!) and performance of LeCont tyres was extremely constant, helping to work properly on setup, making it possible to compare one setup with the other without having to consider tyre performance deterioration from one session to the other.
Tyres tread reading also gave good indications on hour setup could be changed and great confirmation of results obtained, in addition, of course, to what at the end always counts morelap times! Still, good and uniform tyre wear can also give us constant and good performance along the whole race.