Michelin Cup 2 lasting only two track days
03-08-2016 | 06:28 PM
#31
The Penguin King
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From: Houston
That is certainly not normal wear and not typical for these tires.
Several culprits come into play.
Pressures
Are you keeping an eye on tire pressures? Street tires will go up 12 pounds or more at the track. This is nothing like what you see on the highway. If you don't bleed them they will be wildly over pressure and cook that much more. Over-pressure tires will not perform well, can be damaged and are in fact dangerous. Certainly an over-pressure tire will feel greasy. Just as an overheated tire will also feel greasy. You need to start at a lower cold pressure than normal and bleed them out through the day. At the end of the day, you will need to put air back in. Are you checking your pressures?
Driving Style
If you are grinding the outside edges of your front tires, you are understeering and just grind the tires to death. Thats not the fault of the tires. You need to consider your driving style and not try to force the car to turn, tires screaming in protest.
Alignment
Alignment is going to be a compromise. A typical stock alignment is designed to wear well on the street. The toe & camber is set to make the car safer and the car wants to go straight. With a track alignment the car wants to turn. Not necessarily what you want on the street. Typical street alignment will show more shoulder wear and understeer at the track. Typical track alignment is optimized for turning and hard cornering. Track alignment will handle better on the track and wear better because it is optimized for the constant state you are in on the track: turning. Of course, that track alignment also means that the tires will wear more on the street and the shoulders will wear faster on the highway when you are not turning.. You can compromise with a slightly more aggressive alignment. Pick your poison.
If you are wearing the shoulders, you are grinding the tires. Guess what? That produces heat. More heat==more pressure. More pressure+more heat will cause the chemical reactions in track rubber that we associate with heat cycling. And of course all that greasy effect will just mean the tires slide that much more, wear that much faster and on and on and on...
Consider all of the factors mentioned above.
Several culprits come into play.
- HEAT
- Driving Style
- Alignment
Pressures
Are you keeping an eye on tire pressures? Street tires will go up 12 pounds or more at the track. This is nothing like what you see on the highway. If you don't bleed them they will be wildly over pressure and cook that much more. Over-pressure tires will not perform well, can be damaged and are in fact dangerous. Certainly an over-pressure tire will feel greasy. Just as an overheated tire will also feel greasy. You need to start at a lower cold pressure than normal and bleed them out through the day. At the end of the day, you will need to put air back in. Are you checking your pressures?
Driving Style
If you are grinding the outside edges of your front tires, you are understeering and just grind the tires to death. Thats not the fault of the tires. You need to consider your driving style and not try to force the car to turn, tires screaming in protest.
Alignment
Alignment is going to be a compromise. A typical stock alignment is designed to wear well on the street. The toe & camber is set to make the car safer and the car wants to go straight. With a track alignment the car wants to turn. Not necessarily what you want on the street. Typical street alignment will show more shoulder wear and understeer at the track. Typical track alignment is optimized for turning and hard cornering. Track alignment will handle better on the track and wear better because it is optimized for the constant state you are in on the track: turning. Of course, that track alignment also means that the tires will wear more on the street and the shoulders will wear faster on the highway when you are not turning.. You can compromise with a slightly more aggressive alignment. Pick your poison.
If you are wearing the shoulders, you are grinding the tires. Guess what? That produces heat. More heat==more pressure. More pressure+more heat will cause the chemical reactions in track rubber that we associate with heat cycling. And of course all that greasy effect will just mean the tires slide that much more, wear that much faster and on and on and on...
Consider all of the factors mentioned above.
03-08-2016 | 06:51 PM
#32
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From: All Ate Up With Motor