*My Tires*

Dunlop SP2000

Starting 9/1995:

The first set of tires were the Dunlop SP2000s that came with the car's sport package. Tire size is 225/50ZR16. Wheels are 7x16 ET46.

I didn't have much to compare them with, but I noticed that as they aged, the wet traction became terrible. It made for nice slides in the rain but was not confidence inspiring at all. There was minimal squeal or protest even beyond the limit. I got about 40000 km (25000 miles) out of them. They could have gone more, but because of my low mileage driving, the compound had hardened and was barely wearing down anymore. With the poor wet traction and also not very good dry traction due to the hardening, I got rid of these. About time since I had three punctures (and thus 3 plugs) in 3 different tires.

Continental ContiSportContact

Starting 9/2000:

I picked up a set of Continental ContiSportContact that came off of an E46 3 Series. In comparison to the SP2000s, these had slightly poorer dry traction and squealed a bit more at the limit. But they were more predictable and had a better ride quality. Wet traction was a major step forward, even towards the end of their life after another 47000 km (29000 miles), which was pretty good treadwear considering the numerous autocrosses and more aggressive alignment (up to -2.0 degrees) on these tires for much of their life without rotation. Again, the nails caught up: two punctures, two tires, two plugs. Here are some photos of these tires after they came off the wheels:

Front left:
Outside of tire at bottom/foreground
0" tread on inside block
2/32" tread towards outside block
0" tread on outer edge
  Front right:
Outside of tire at bottom/foreground
0" tread on inside block
2/32" tread towards outside block
0" tread on outer edge
Rear left:
Outside of tire at bottom/foreground
1/32" tread on inside block
3/32" tread towards outside block
  Rear right:
Outside of tire at bottom/foreground
1/32" tread on inside block
3/32" tread towards outside block

Yokohama AVS ES100

Starting 3/2003:

Please see http://www.bimmerforums.com/forum/showthread.php?s=&threadid=82478 for continually updated information.

Summary: An inexpensive, soft riding tire that grips well in the dry with slow transient response and large slip angles due to soft sidewalls.

Disclaimer: I have a semi-custom adjustable coilover setup with retuned anti-roll bars, so tire problems show up quite readily. A stock car may not reveal the problems that I've witnessed as severely. I haven't been able to take these tires to the track or autocross like I did with the other tires.

Background: My previous two tires were Continental ContiSportContact and Dunlop SP2000. All tires are 225/50ZR16. I have used these ES100s for about 5300 miles and just dismounted them.

These tires suffer from very slow response and large slip angles that are quite noticeable from speeds of 40 MPH and up and become dangerous above 80 MPH. There is a vagueness at turn-in; the front tires then take a set, and then a split second later, the rears plant themselves. What this translates to is a slow initial response and then a sudden build up of cornering forces and yaw angle. The tires give a rubber band feel as they progress (non-linearly) from straight ahead to the final slip angle. The final slip angle is large so it feels like I'm drifting the car, at least compared to other tires I've tried. Basically one has to wait for these tires to settle. If not, and you crank in more steering, you'll have overshot and need to relax the wheel a bit. If I accelerate out of a corner and then push the clutch in and let it out at a higher RPM, it's very obvious that the tires compress and shear quite a bit before really grabbing. The softness of these tires is noticeable even visually from the roll angle of the car in turn-in and in slaloms! Also, if I hold a small, steady angle at freeway speeds and then suddenly release the wheel, it will snap back to center, overshoot back and forth before settling down. They also tramline more and requires more steering corrections with crosswinds. This is true even with high pressures than my previous tires. I've also tried to adjust my shock settings but have determined that the problem is really in the tires as I can't get rid of it at all. I tried a set of used Bridgestone RE730s just to make sure I was properly calibrated, and the RE730s had better response even though they had been sitting around and only had 20+ PSI in them!
In the wet, engine torque can break away the rears much more easily than the ContiSportContacts. And when they do break away, they don't regrip as naturally, therefore requiring significant correction. The front also breaks away early in the wet, suggesting that this compound is still not that great for the wet. I can also spin the wheels more easily accelerating in the wet.
After a couple thousand miles, the tires started to whirr around 35 MPH and 20 MPH. More recently, the whirring has started to become evident at most speeds up to 60 MPH or so. There is also some whirring during hard braking, but that happened on the Michelin Pilot Sports as well that I drove on, so it may be a characteristic of directional tires. The tread pattern tends to throw up a lot of rocks into the wheel well area.

These tires were quiet except for the specific speeds mentioned above. They are also quiet when loaded up (they do not squeal very easily). I have not had any problems with hydroplaning. But then again, I've not had problems with my other tires either. In the dry, the front tire can really grip relative to the front in tight corners, dialing out some understeer and allowing me to steer with the throttle. The large slip angles make these a good training tire for drivers to learn yaw sensitivity. Ride harshness is the best among the tires I've tried in the same size and on the same car. They will absorb the small disturbances in the road quite well to reduce impact harshness.

Continental ContiSportContact (2nd set)

Starting 7/2003:

Bridgestone Blizzak LM-22 (snow tires)

Starting 11/2003:

These are the snow tires that I got slightly used (already mounted on wheels). I'm impressed with the dry and wet behavior. There is barely any more noise than regular summer tires, and these squeal even less than my ContiSportContact summers! Instead, you just hear a bit of grinding as the tire rolls onto its sidewalls. In normal, mild driving, there's actually very little perceivable difference, so I can see how many drivers can probably live with these tires year round! This is Bridgestone's highest performance snow tires and are H-rated, so that's probably why. However, push them just a little bit harder than what's considered normal, and the lower cornering stiffness becomes apparent. It's not too obvious at first as I dial in my steering lock. However, once the throttle is lifted, I realize how much the rear tires were already taxed. This is the first set of tires in which I can get very significant lift throttle oversteer. In fact, I'm always preparing myself for that when accelerating through on- or off- ramp, looking ahead to make sure that I don't have to lift the throttle farther down. Power oversteer can also be had much more easily. The only time when I had any easier power oversteer was with my PSS-9s with the front anti-roll bar disconnected! So these are indeed "fun" tires to drive in the dry. They're not as annoying (loud, squirmy and soft) as what others normally say about snows tires, but I've not had any other snow tires on this car, so it's hard to compare.

In the snow though, I can't say I'm impressed. Being the most dry highway snow oriented tires from Bridgestone, I guess that's not a big surprise. These also don't have the special Multicell compound that many of the other Bridgestones do. Starting traction is better than on summer tires of course, but I can't say it's a night and day difference. I guess it's not fair that my only other serious winter driving this season was in an all wheel drive 325xi, but even with comparing the braking and cornering ability in the snow where all wheel drive doesn't assist, I don't think these tires are any better than the all-season Michelin Energy MXV4s that are on the 325xi. Fortunately I'm in Detroit now and there are very little hills. I still definitely do better than most cars on the street which seem to spin their wheels like crazy, but I also have to be very judicious in throttle application because even before I notice a wheel spinning, the car's already trying to rotate. That seems to be the first response--rotate instead of wheelspin. For my next winter tire, I'll probably trade off some dry performance for better winter traction.

November 24, 2004 entry:

Wasn't planning to put them on today, but a quick brake and gas on the Eagle F1 GS-D3's made me think otherwise. The sleet was freezing on the ground. These are a little less harsh over impacts but not as large as one would think for 50 aspect ratio snows vs. 45 aspect ratio max performance summers. The biggest difference is that it's a lot less sensitive to road crown and bumps. It's a lot more relaxing driving these, especially over truck ruts where the F1 GS-D3's would tramline a lot more...almost unacceptably now that they're wearing in. These Blizzaks do whirr a bit at all speeds. Not enough accumulation today to have too much fun. Just a bit :)

Goodyear Eagle F1 GS-D3

May 5, 2004 entry:

Put the Eagle F1 GS-D3s on today (225/45/17 mounted on 7.5x17 forged wheels). Did the fronts first and went for a drive to make sure there weren't any major vibrations from wheels being bent or unbalance. Felt fine but very plush, even softer than my 16" Contis. Didn't do any handling.

Then went back to the garage to put on the two rears. Checked pressures to be in the mid-20s. No wonder! Pumped up to mid-30s. Some of the harshness came back, but they still are comparable to my 16s (both the summers and the snows).

The 16" summer Conti combo are about 39 pounds. The 17" GS-D3 combo with the forged M wheels are about 43 pounds.

Did some gentle inputs. Doesn't feel any sharper, but felt very smooth and linear, more so than the Contis and definitely more so than the Yokos. Steering feels slightly lighter, and a bit more tramlining. No major difference in noise level on the roads I drove. Didn't push the tires hard yet...will wait for a bit.

June 20, 2004 entry:

Best tires I've had yet. (Disclaimer: It's also my first set in 17".) Front end keeps biting, particularly amazing given proper trail braking. Braking performance is also surprisingly good. Several times I've braked hard, thinking that I'd get into the ABS soon, but I don't. Has a tendency to pull to the left. Given that my tires immediately before these didn't do that, I suspect that it has a different PRAT rating to counter road crown, but it is a little too much. Seems to generate vibration at 85+ MPH, but nothing through the steering wheel. Did a front/rear swap to see if would show up in the steering. It didn't, and the vibration seems to be a bit better. Ironically, the left hand pull is less now. Maybe the tire with the out-of-spec PRAT is now in the rear with less effect on drift/pull. Wet performance is superb. So far, I've been able to drive as hard as I do in the dry, except in first gear out-of-intersection-corners where I can still snap the rear end out given that I get to my peak torque at the right point in the curve. Tried to do a drop clutch start from 5000 rpm, but still couldn't spin the tires loose in the rain!

October 17, 2004 entry:

I got the tires rebalanced a while back, and some of them were out of balance...not surprising since the first store didn't put any weight on and claimed they were in balance! It helped but didn't get rid of the vibration entirely on one of the pairs. Took that pair to a place with a road force balancer (applies about 700 lb to measure the road force variation) and found that one corner had a 30 lb variation. The Hunter GSP9700 said that 29 of the 30 was from the tire, but that it could be reclocked (tire rotated relative to wheel) to bring the assembly's force variation back into spec. So it was reclocked, but it was no better...still showed 30 pounds of force variation. They pointed out something interesting to me though...the treadwear on the left tires differs from the right tires. I think this is because both of my left wheels have a bit more negative camber than the ones on the right side, so while the right side ones wear evenly, the lefts wear more on the inside, and this has caused some of the shallower tread to remain on the outside tread blocks on the left tires but not on the right tires. I wonder if that is causing the drift/pull. I guess I'll wait until all the shallow tread has worn out to see if the drift/pull cancels itself. Take a look at the photo below, which I took since I rotated them today after my front brake service:

The tires also seem more sensitive to road crown and ruts now. It's not unacceptable, but it's caught me by surprise a few times. Either that or the ruts themselves have gotten worse!

November 24, 2004 entry:

It's raining @ 3.5C/38F now, so I thought it'd be a good time to test these Y (Z) rated tires in the cold. In a familiar left turn, I went in slightly on-throttle and it plowed significantly with that buzz through the steering wheel. The speed scrubbed off a bit, and the rear came way out...that I actually had to use quite a bit of countersteering...both on the initial spin and the rebound spin. These tires are great in the warm rain but not the cold rain. Perhaps the old ContiSportContacts aren't that bad after all. They weren't great in any particular situation, but those stay consistent regardless of temp and age....

September 23, 2006 entry:

My rear tires wore out in June with zero tread in certain sections, and the fronts only had a little bit left. Unfortunately I didn't get to take photos before discarding these. In the last few months, grip levels dropped noticeably in the dry as well, but the overall characteristic was much more oversteer, which worked well for me in a low speed autocross event. In mountain driving, I played around with tire pressures and found it better with a higher rear pressure. Wet grip still stayed acceptable though, even though it was nothing like what they were when new. Rut wander/tramlining got worse with time too, almost to being unacceptable, although I found out recently that at least one front ball joint was worn, so that may have been a contributor. These tires never got noisy with wear, which is quite an achievement. However, secondary ride (impact harshness) was much worse as the tires wore. It literally felt more like plastic or "thin rubber." But overall, I've been pleased with the performance of these tires as they are without doubt the best I've had so far.

Bridgestone Potenza RE050A

September 23, 2006 entry:

In June, my Goodyear Eagle F1 GS-D3 tires wore out, and I decided to try the Bridgestone Potenza RE050A's, partly because I've always wanted to try Bridgestones (like the RE730's, S-02's, S-03's) but never did because they tended to be expensive. However, Tire Rack had a large sale of these RE050A's, apparently to make way for the Pole Positions. So although the RE050A's that I got were not Bridgestone's flagship, they are the predecessors to the current flagships and quite commonly appear as original equipment, anywhere from some Mazdas (MX-5, Mazdaspeed6), BMW's in their runflat variants (3 series, Z4), Aston Martins and Ferraris.

These tires run wide, as shown by their specs, warned by the Tire Rack rep and also visually apparent. However, because I had a worn front ball joint, followed by an overheat and blown radiator, my alignment was delayed and did not really evaluate the tires until more recently, now with 4500 miles. In any case, this is more a comparison of the Goodyears and the Bridgestones....

Unmounted, the Bridgestones are definitely stiffer and would hardly deflect with body weight or squeezing of the sidewalls, so I expected a very harsh ride. Surprisingly, they had much better impact harshness and overall secondary ride than at least the used Goodyears. How they compare to the Goodyears when new, I don't remember, since Goodyears got harsher with time, just like my previous Continentals. So the better ride of the Bridgestones despite their higher sidewall stiffness was a nice surprise, and a mystery.

I had a mechanic at work match mount these to minimize force variation, and he was able to get the radial forces down into the teens for a pair (which I put on the front axle) and low 20's, which I put in the rear. My wheels were used and have been repaired, so I think these values are acceptable. Nibble (vibration in the steering wheel at speed) is noticeably reduced, especially after I replaced the control arms for the ball joints, and there is no significant drift/pull. Rut wander/tramlining are also better than the old Goodyears.

However, the Bridgestones trail the Goodyears in grip, at least slightly in the dry (I'd need to be very extreme to push too hard in the dry) and very noticeably in the wet, in braking, cornering and acceleration. Now the new Pole Positions flagships do earn an "AA" wet traction rating, like the Goodyears, but my RE050A's that I got do not, so I did expect some difference, but not this much. I'd say that the Bridgestones have the wet grip level of midlife Goodyears. However, the Goodyears got very loose with aging, and these new Bridgestones brought me back some understeer.

Noise-wise, the Goodyears were amazingly quiet through their entire life which, as I have learned from others and from the vehicles I've experienced at work, is not something to be taken for granted. Right from the start, the new Bridgestones seem a bit louder, not necessarily from an overall level perspective but from the presence of some distinct whirring/rumbling. It's currently not annoying and not noticeable unless I'm listening for it, but I wonder if it'll be worse with time, as that tends to be the case with Bridgestones, so I hear.

The steering and transient response are the most disappointing aspects of my new Bridgestones. I had read this on some reviews prior to my purchase but decided to take the chance. Some of you may remember that I had serious complaints about the Yokohama ES100's several years ago, so much so that I sold them after unsuccessfully trying to tune them better with air pressure adjustments and changing damping on my adjustable shocks back then. The Bridgestones exhibit a similar problem. At 60 MPH and higher, if I give a quick enough (step) steering input, the car would turn in as expected and then suddenly turn much more, creating greater yaw and sideslip than expected, at which point I'd have to back off on the steering input. At 80 MPH and higher, it becomes quite annoying when making larger corrections. Below that, it's only an annoyance if I'm purposely trying to jerk the steering wheel. I guess if I were super smooth, it would never bother me, but I don't think this is very safe. I suspect some of this could be due to my new front control arms which give me increased caster and unknown bump steer characteristics, and some of it from my new alignment which runs very little toe on both the front and rear, but I decided to play with tire pressures anyway. From 32/34, I went to 30/36, to 36/32, 32/36 and am planning to go back to 36/32, or thereabouts. The nonlinear steering response is definitely very sensitive to pressure, unlike the ES100's which was just way out of the box. I'm just surprised that a higher front pressure is the solution since intuitively and from some of the notes I have from class suggest that such behavior is usually caused by a lack of rear tire stiffness. I guess this is a different mechanism. So fortunately I've been able to tune out of the nonlinear steering in this case, but I have a feeling it would come back if I drove at even higher speeds, but I'm not going to be too concerned about that :) I'm interested in seeing how this might change over the tire's life, and if the restriction of running higher front pressures would affect my ability to tune for balance on the autocross and mountain driving....