dwe8922

Hi everybody,
I took my Toyo's off after Roebling last weekend, and was a little surprised about the wear pattern. Before the event, I asked about running them in reverse here: https://rennlist.com/forums/racing-and-drivers-education-forum/427179-can-r-888-s-be-run-backwards.html ..

Well, I ended up not switching them right to left, and the left front really got chewed up compared to the others. The left side gets the most wear at RRR, but I've run RRR a good bit in my 993, and have never had so much LF wear relative to the other tires as I did this time in the 360 Modena. I started the day targeting a hot pressure of 38, and ended up feeling best around 34-35 hot. My alignment specs are (challenge stradale specs):

Camber LF:-1.4, RF:-1.5, LR:-2.0, RR:-1.9
Toe LF:0.10, RF:0.10, LR:0.19, RR:0.20

I also measured the tread depths: (divided tire into 1/4's; going outer to inner

LF(mm): 2.3mm, 2.5, 2.5, 3.2
RF: 3.6, 4.1, 3.7, 3.8
RR: 4.0, 4.2, 3.6, 3.8
LR: 3.6, 3.2, 3.3, 3.5

Below are pictures of the Left front, left rear, and the shoulder of the LF. It's weird that one side of the groove is lower than the other, and the higher side had developed those "flaps". Only the outer half of the left side tires has done this. Also, the outside corners have worn a lot more than I expected on the left side, since the tires felt overinflated and greasy on the first day. Any suggestions?

weneversleep

All of my R888s have this "flap" that develops on the grooves, I don't know why--it's my first set of R888s, in fact, my first set of R-compounds.

I'm driving an E36 M3, with -3 front camber, -2 rear camber, and coilovers. Corner-weighted.

M758

I have seen that on all the R888's and also on the RA-1's. Although with the RA-1 the ridge would be different due to the different tread pattern.

Here my newest set of RA-1's. These started Full tread and have 7 heat cycles on them and I guess have about 6/32 still on them. This is quite normal for these tires. As you can see they have the same rolled up edge, but it is just sits different on the tire. It is always on the "outside" of the tire as well.

In time they wear down and this goes away as the tread depth goes down. I believe it will on the R888 as well.

Scootin159

I had the same groove on my RA-1's as Joe. Has also gone away as the tread depth wore away.

chrisp

If you notice, the flap is always on the edge of the groove that's to the outside of the turn you are taking. Basically what's happening here is that the rubber on either side of the groove is unsupported and when you corner the rubber on the outside of the groove is flexing into the groove and doesn't wear against the track surface as quickly. Then when load is taken off, it flexes back and since that portion of rubber is less worn, you end up with the flap. If you could see inside the groove while the tire is cornering you would see that the groove is closing in on itself with that flap of rubber. As noted, it goes away as you wear the tire because the shallow the groove becomes, the better supported that edge of rubber is an the less it flexes into the groove.

dwe8922

I've seen the flapping before with other tires I've had, just not to this degree. Thanks for the explanation of why.

Any suggestions for lessening the burden on the LF tire at a track like Roebling? I've always combatted this by swapping tires right to left, but I've never seen this much wear on one tire relative to the others. Perhaps I need to go to -2.0 deg camber in the front?

Also, the left side tires seem to show more outside corner wear than the others. But, the wear line seems about right relative to the arrow mark (showing not too little pressure), and the depths are pretty even across (maybe could use more camber) not showing signs of ballooning in the middle from too much pressure.

Thanks!
David

jrgordonsenior

A couple of thoughts..... The flapping as pointed out by others apears to be common in this tire. It does it on my Spec Boxster and then disappears. Porsches like your 993 are light in the front end unlike lke your CS which may account for your LF tire wear. I would keep try the front pressure back up in the 38 range while keepinmg your rears lower for traction. I would also try to brake earlier so you could get back on the throttle sooner shifting the weight to the rears. You don't have a lot of neg. camber in those wheels so I would imagine you getting lots of push turning into the corners. The fronts are probably scrubbing across the pavement under those conditions. Have someone take you temps in the hot pits, that will tell you everything you need to know...

333pg333

I run more than -3 on mine. Although different cars, Toyo suggest that they respond best to pretty large neg. I would contact your vendor or Toyo themselves to get more info.

dwe8922

Just some additional info. I put the car on the scales at RRR, and this is what I got:

2000 F360 1/3 tank of gas(saddle tanks rear)
Total: 3182
RR:906 LR:926
RF:686 LF:664

With me in it
Total: 3387
RR 909 LR 1005
RF 718 LF 755

I didn't expect the car to weigh this much. The balance of the car feels very good though. It was very neutral, and didn't really have any understeer. Also, the F/R brake pads/rotors are the same size, and seem to be wearing at the same rate.

SB

I run r888 on my 997s. These tires like camber, but not a crazy amount. I run -2.5 deg in the front and -2 in the back. Front tire temp spread is excellent(ie insides are about 5-7 deg hotter then the outside), and rear temp spread is about even across the thread (which to me suggests I need a bit more camber in the back).
Keep in mind that camber settings are highly dependant on suspension geometry, which is probably quiet different on f360.

SB

one more thing to add is that I didn't notice this wear pattern on my set. Also, i found tires to be VERY sensitive to tire pressures. In my experience, the tires like about 34 psi hot, and start to feel greasy probably around 36.
PS. For reference Pilot Sport Cups like more camber...in the 3.5 degree range.

tdf360

You need to get those scales looked at, those numbers are just wrong. The 360 is rear weight biased, not front. Actually, it looks like you just transposed front and rear.

Here are the numbers from my '05 F430, 1/2 tank gas:
LF 793 RF 796
LR 973 RR 976
TOTAL 3538

Gary

dwe8922

Thanks Gary for pointing out my mistake with the numbers. I've corrected them in my post above above. If your shop did your corner balancing with you in the car, they did a terrific job.

SB-That's the hot pressure I did best with (34-35), where most of the recommendations I got, including from the Toyo website, recommended high 30's to low 40's. What cold pressures did you start with?

mooty

i have used up 5 sets of R888.
from the pix you posted, the wear is even and normal.

tdf360

Props to Custom Alignment in Mt View for the corner balance. I was impressed how close they were able to get it. They worked on it all day. They put weights in the seat to simulate the driver.

Gary