Sorry for the double post, I did not see this forum catagory... sorry.
I decided to write this review on the basis that many of my fellow Subaru owners are presently running Kumho 712’s and love the bang for the buck they offer. First let me say what I liked/disliked about the Kumho’s then I will move on to what I chose and why to replace them with. Let me let you know that I am running: 2002 WRX with B4 17X7” wheels, on a stock suspension with Kartboy endlinks and a whiteline swaybar. I have a Tubro XS stage one kit with Samco Intercooler Hoses installed. I have also changed out all my fluids to Royal Purple (actually did make a difference!)
First and foremost, lets not kid ourselves. Kumho’s are inexpensive. They are not the best tire on the road, but for a UHPT (ultra-high performance tire) they do certain things quite well. The first thing that I have to say about the Kumhos is that they offer pretty good turn in. This is probably attributed to its large square tread block and stiff sidewalls. I was always pleased by the Kumhos ability to change direction. Where I found they faltered was in holding that level of grip. The Kumhos could not tame the WRX’s tendency to understeer completely. They were vastly better than the RE92’s, but tire squeal in mid corner usually meant early lift to settle the car back down. The Kumhos due to there hard sides did allow the tire to hop more over sharp changes in pavement (usually associated with potholes, uneven pavement, etc) and this was mostly noticeable on hard braking where you could feel the tire come out of contact with the road. This is the same reason that the Kumhos are also not the smoothest tire to own. Mine allowed me to feel just about every expansion joint, dip or bump in the road once they got past the first 25% of tread. But to most, this is not important because being a luxury tire is not what the Kumhos are all about.
Wet weather traction was good, and I never felt anything but confident when the heavy Houston rains fell. The Kumhos just kept on sticking, although their lack of mid corner grip was heightened as I could easily outpower the front wheels ability to turn, making the AWD work to keep me out of many a ditch. Even when the tread was 80% worn, I still had little issue with wet roads and the Kumhos behaved admirably.
One area that began to become an issue was with tire noise. Again, these are not a luxury tire, but the Kumhos had a harmonic at about 40 mph that after a while had me wondering if I had a bad bearing in a wheel. Most people who want a performance tire a great price will not care about this, and it did not really make me lose sleep, but its worth noting in the sake of being thorough. The last thing I want to talk about is treadlife. Now when purchasing performance tires, we make concessions in this category accepting the fact that they have a short life span. The Kumhos survived two driving clinics, and a couple of autocrosses along with the 24000 miles of service they provided. When taken off, they were still not on the wear bars, but were close enough for me to replace. I have never been one to be cheap with tires, they are without a doubt the most important part on the car.
Okay with that being said, I started looking for new tires that would again meet my need for great performance along with a great price and this time local availability would be important. I have ordered 4-5 sets of tires from www.tirerack.com
and have had nothing but good results from them. The only other place that comes close is my local discount tire company. Well, I had several choices in what tires I could install. Without going into the details about what I did not choose, I wanted to tell you what I did choose and why. I am presently running the Yokohama AVS E100 in a 215/45/R17. Basically the factory recommended size. Why the Yoke? Well, basically it offered improvements in every area where the Kumhos fell short ON PAPER! I read reviews that both praised these as the best thing since superglue, and as soft and slippery as melted jello. So what is an average consumer to do? Well you trust hard data and filter out opinions from less educated people who may have an entirely different background than you do. It just so happened that Luke from Tirerack posted an article with regards to a road test they did between the Kumho 712, the Sumitomo HTR(something or other), and the AVS E100. Oh my, how lucky for me!!!
Well it was very clear, again on paper, that the AVS E100 was a league above what the Kumho had to offer. It was also a few bucks more per tire, but fact that it was a notch above in every category justified the cost to me. So off to get these put on. The first thing that all former Kumho owners should know is that these Yokes can handle more pressure than the Kumho’s. I think the max in the Kumhos was 44 psi, while the Yokes can handle 51. I cannot get into why this is, but I will tell you that the Yokes like the elevated pressure.
The first thing I noticed as I pulled out was the decrease in initial turn in and directional changes (KEEP reading potential buyers don’t get discouraged). I pulled into a gas station and checked the pressure. The little needle pointed to 37 psi. A tad low considering the 51 max. However I should note that I ran my Kumhos at 37-38. Well I did not add air right away because there is an initial tire break in that you must drive through. Tires have a mold release agent on them when new, as well as the grease and grime from being stored in the warehouse. All this must be driven through to get to the fresh rubber. My first real sensation was that its amazing how much tires can effect the way a car drives and feels. My WRX was not the conduit for every bump and dip. It was a far supple ride. I was thinking that the softer sidewalls that led to a less crisp turn in are also helping me out in ride quality. My Girlfriend will love this, but I am looking to improve my handling, not move laterally or decrease it. Just another note about these tires. The first things I noticed visually before driving off is that the shoulder blocks are a little more rounded than the Kumho, making directional changes a little more subtle and not as knife edged.
My first feel for the great grip these tires provided was turning through an intersection. I was first and really rolled on the throttle to see what it would take to break them loose. Knowing that they had barely 2 miles on them and far from broken in I wanted a preview as to what lay in store for me in the next 20000 or so miles. Well turn in was probably every bit as good as the Kumhos, it just did not feel like it, as its not as twitchy, but where I was shocked was with the mid-corner grip. This tire really goes where its pointed. Where I would sometimes push to the second lane due to the Kumhos starting to give up, the Yokes kept on tracking where I wanted them really biting the street. I started to smile at this point, because I knew things would only get better. On the way home from work I tried a similar move on a fast on ramp and again, these tires just hold on completely through the curves. Before I went home I stopped in a gas station and increased the pressure to 45 psi all the way around. I still wanted room to play with should I need to go up more. Well it made a large improvement in the way the car turns in. It feels more instant now and less vague. Still not as sharp as my near slick Kumhos were, but extremely close, and I would wager better than new Kumhos would be. Its only been two days, but so far I am very pleased with the grip, the turn in, the ride quality, and most definitely the noise level. Did I mention that these tires are very quiet (at least compared to the Kumhos). A win-win situation. I will write more once I get them fully broken in, but Yokohama has done a wonderful job of putting a great tire on the market at a very reasonable price. For all you Kumho Ecsta 712 owners out there, I strongly recommend the AVS E100.
Thanks for reading!
Next report will be on the Turbo XS stealth back when added to a Turbo XS Stage I unichip package.