Let me start by saying that the following comments are only my point of view based on my amateur observations! A few people have asked for feedback regarding the latest version (2-17) of the Nankang AR-1 Medium compound tyre. I have the standard 18” rims and use 235/40/18 sizes on my RS250 Cup. I include here a couple of videos showing the grip levels of the Nankang AR-1 on a typical dry track and also on a damp track at the Nordschleife and a summary of my experiences below. Conditions: Air temp approx: 24 degrees Track temp approx: 27 degrees Car: Renault Megane RS250 Cup. Camber at 2.75 degrees neg front and 2 degrees negative rear. KW Club sport coil overs. Tyre Pressures: Front 2.5 Bar Rear 2.6 Bar Tyre Condition: New scrubbed (6 laps) Conclusions: Tyres appear to have very stiff side walls and require increased running pressure to counter under-steer at lower pressures. Pressure range is large from cold to hot. When hot at 2.5 Bar leaving over night pressures reduce to 1.6 Bar at 19 degrees in garage by morning. Constant pressure regulation is recommended and one can “feel” when the tyre is operating either over or under the optimum pressure by the feedback in the handling of the car. Once the optimum temperature and pressure is reached then the effective working window of the tyre can be consistent especially on a less demanding track and for fast road use. The tyre is noisy in corners with early “squeal” but this does not affect the performance and could be due to the track surface at the Nordschleife. The tyres are able to reach operating temperatures quickly and maintain them over three laps (65kms) before one can feel overheating becoming an issue. Once the tyre becomes too hot then slip is felt. This is at the front axle first by under steer which is progressive and controllable. Wear rate is very good by comparison to other makes and after 37 laps (including warm up laps) the tyres still look in very good condition and I would expect to double the distance. Shoulder wear is less than on other brands which will help in longevity. Estimated performance comparison would be in my opinion perhaps 5-10% less than a Dunlop Direzza and 20% better than the Federal FZ-201. In the “damp” video both the track and tyre temperature were decreasing and you might see that the car rotates more easily and grip levels begin to reduce at the end of the lap, this I think is a combination of track surface conditions and tyre temperature combined. The tyre is a semi-slick and driving on track and road in wet conditions is not recommended. From hot the effect of quickly reducing pressures and temperatures, if caught in a rain shower for example, would change the operating characteristics of the tyre completely. Aquaplaning due to the semi-slick nature of the tyre is also a possibility! Please remember this is only my opinion and I hope the information is useful for some forum users. Safe driving.
Excellent info there Paul, I'll see you there last weekend of Sept, staying at Apex before heading to Spa for a trackday at the start of the week
Thanks for your comments. I think you are staying at Roberts Apex in Nurburg not with me at Apex-Apartment.Com (original and best ). Just had a back surgery last week so no more driving this year for me. My cars are (RS250 and R26R ) are for sale with German registration. It's possible that a buyer could register the car here and have fully comprehensive insurance for the Ring. I even have garage space for storage! I wonder if that could interest anyone?
Aye staying in Nurburg, shame about no more driving for the season but you've probably done enough anyway so far haha!
