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Opinions on tire wear please....

 
Old 01-27-2019, 01:47 PM
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JTT
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Default Opinions on tire wear please....

Please provide opinions on this tire wear. Michelin Pilot Super Sports, 11,000 kms (6800 miles). Inside edge is to the left.




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Old 01-27-2019, 02:03 PM
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You need a 4-wheel alignment
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Old 01-27-2019, 02:25 PM
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Originally Posted by Byprodriver View Post
You need a 4-wheel alignment
Need new tires too . Seriously though, it was aligned actually twice during this period. All within spec except a a tiny bit of excessive negative camber
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Old 01-27-2019, 02:27 PM
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Scott at Team Harco
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You either need to corner harder, or reduce the negative camber.
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Old 01-27-2019, 02:37 PM
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Originally Posted by Scott at Team Harco View Post
You either need to corner harder, or reduce the negative camber.
+1
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Old 01-27-2019, 05:38 PM
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Time for new sneakers and alignment. If it was aligned 2 times during those 6800 miles you have some worn out suspension parts.
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Old 01-27-2019, 06:09 PM
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Originally Posted by Scott at Team Harco View Post
You either need to corner harder, or reduce the negative camber.
No doubt, a little of both. Does this look like a camber issue or toe issue? The extreme edge wear makes me wonder if it might be toe related, but I'm looking for expert opinion.
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Old 01-27-2019, 06:31 PM
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Scott at Team Harco
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Originally Posted by JTT View Post
No doubt, a little of both. Does this look like a camber issue or toe issue? The extreme edge wear makes me wonder if it might be toe related, but I'm looking for expert opinion.
It's almost impossible to tell without having it checked. Too much toe out will wear the inside of the tire as well.
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Old 01-27-2019, 06:38 PM
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+1 on all input given so far...

what about the other front tire?
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Old 01-27-2019, 06:49 PM
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Thanks Scott, and others. I appreciate the input from those with experience with tire wear and alignment.

I wish I had kept the alignment printout to compare specs. I lowered the car, approx 30mm last winter before putting on these tires and realigning. I had asked for to be at the mildest end of the spec spectrum. With the lowering, negative camber could not quite be brought into spec, but was close to higher negative camber end of the spectrum. Toe was set to as close to zero end of spectrum as they could get (very mildly toed in), and well within spec. Since I have been trying to learn a little about alignment specs and 996 suspension to try to understand how it all works.

From what I've read, it would appear that 996 multilink rear suspension tends to toe out on compression, which seems to make sense looking at the arc of the links with the wheels off. This got me wondering if having almost zero toe in at static, might actually be creating a situation of excessive toe out under load, or accelerating? There is a very good chance I'm way off on this, but I throw myself to the collective of much smarter people than me here at Rennlist. Previous to lowering, tires also seemed to wear most heavily on inside edges, although not quite as bad.
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Old 01-27-2019, 06:51 PM
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Originally Posted by golfnutintib View Post
+1 on all input given so far...

what about the other front tire?
Sorry, missed you comment while I was replying to others....first this is the rear not front. Fronts are wearing evenly. The other rear tire looks virtually identical.
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Old 01-27-2019, 06:57 PM
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Scott at Team Harco
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Originally Posted by JTT View Post
Thanks Scott, and others. I appreciate the input from those with experience with tire wear and alignment.

I wish I had kept the alignment printout to compare specs. I lowered the car, approx 30mm last winter before putting on these tires and realigning. I had asked for to be at the mildest end of the spec spectrum. With the lowering, negative camber could not quite be brought into spec, but was close to higher negative camber end of the spectrum. Toe was set to as close to zero end of spectrum as they could get (very mildly toed in), and well within spec. Since I have been trying to learn a little about alignment specs and 996 suspension to try to understand how it all works.

From what I've read, it would appear that 996 multilink rear suspension tends to toe out on compression, which seems to make sense looking at the arc of the links with the wheels off. This got me wondering if having almost zero toe in at static, might actually be creating a situation of excessive toe out under load, or accelerating? There is a very good chance I'm way off on this, but I throw myself to the collective of much smarter people than me here at Rennlist. Previous to lowering, tires also seemed to wear most heavily on inside edges, although not quite as bad.
Toe will remain consistent regardless of accel or decel (unless there is slop in the bushings/ ball joints).
Toe-out in compression, in the rear, usually induces oversteer. I doubt that is the way the suspension is designed.

You would do well to have it aligned to spec and have them take a little off the negative camber spec (go more vertical).
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Old 01-27-2019, 07:03 PM
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Originally Posted by JTT View Post
Sorry, missed you comment while I was replying to others....first this is the rear not front. Fronts are wearing evenly. The other rear tire looks virtually identical.
Oh - that's a whole different story. I thought this was the front.

It's actually so much different that the same things apply. Slightly more wear on the inboard side of the tire is much more common, and less of an issue, at the rear. Dialing out a slight amount of negative camber will help. Much less change than if this were at the front.
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Old 01-27-2019, 07:11 PM
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my tire wear isbasically identical to yours, and I got twenty thousand miles out of my Continental all season tires and I just replace them with some Michelin a few weeks ago. I would not be concerned
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Old 01-27-2019, 07:23 PM
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glad i asked

i agree w scott above - this is kinda normal

if u want less inside edge wear just dial out some rear neg camber, otherwise leave it if the car feels good to you on the move
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