Had my first track day of the season this past week at my home track of VIRginia International Raceway. This was my first time out using Yokohama A052 tires and my new toy of the Apex Pro Digital Driving Coach. Just some general notes for folks that might be considering either of these items:
: I had done some light street scrubbing of these (~60 miles) prior to the event, however this still didn`t seem to be enough. My first session out it took 4 or 5 hard laps before they really started to feel OK. Previously I have been running RE-71rs and happened to get a good deal on these so I thought I would give them a go. My impression so far is that they stick very well, better than the RE71rs when properly setup (see my next note), but there are some distinct differences. These seem to be very sensitive to tire pressure and you have to compensate as such for your sessions. The RE71rs I am able to dial in to my target starting value and they would get heat in them on lap 1 and be stable through the end of a session mostly independent of outside temp or session length. The A052s were much pickier in that regard. In the morning session I went out too low and took several laps to get to the range I needed to be. I compensated in my second session, but then that same setting was overcompensating for my third session an hour later which resulted in overheated tires and a spin at T10. Dialed back for my fourth and they were happy again.
These tires also have a much softer sidewall in comparison to the RE71rs. That is one area I am really not a fan. I was able to adjust to it by the end of the day, but it makes for some very vague feedback and unusual behavior in certain situations. For example, braking into T1 is a ~130-->40mph transition and I find that these tires induce a bit of a "float" effect, much more lateral movement vs the 71s. I was able to adjust, but that was pretty damn unnerving at first!
Final piece is they are significantly quieter vs the RE71rs. Combine that with the softer sidewall and you miss a fair amount of feedback. Going into my spin at T10 there was almost no sound as the tires broke free (T10 is a 80-90mph blind left hander that is also going downhill). I would expect that from a slick, not from a treaded tire.
So, long and short, lots of grip, but vague and sensitive to setup. I will continue to run them, but at this stage I don`t know that I would get another set. They were on special at Tire Rack and were actually cheaper than 71s at the time.
This thing is pretty cool. Last season I was using Harry's Lap Timer (which I have a very strong hate/love relationship with) and decided I wanted to step up a bit on the data front. Thought about the typical Vbox or AIM system but this offered similar levels of resolution and data with the added benefit of realtime analysis and feedback. The realtime analysis is intuitive and useful and the app is equally matched. Both in and post session I was able to utilize the information to make adjustments and push further, which was great, Overall, I am extremely pleased with this little guy and am looking forward to using it more this season