Help with more Cupping on tires....
Thread Starter
JK Freak
Joined: Oct 2006
Posts: 628
Likes: 1
From: Los Angeles
Cupping is almost always the tire bouncing rather than maintaining contact with the road.
Its almost always worn shocks, or, inadequately valved shocks for the tire/axle combo in use.
For example, the heavier the tire, the higher the compression valving that you need to help control that weight and the momentum involved.
If the shocks are in good shape, but have too low a compression setting, well, you can have cupping.
All that bouncing can wreak havoc on other parts too.
Depending on the specific cupping patterns, other things can also be wrong, but, 90 times out of 100, its the shocks.
What shocks/valving are you running?
Its almost always worn shocks, or, inadequately valved shocks for the tire/axle combo in use.
For example, the heavier the tire, the higher the compression valving that you need to help control that weight and the momentum involved.
If the shocks are in good shape, but have too low a compression setting, well, you can have cupping.
All that bouncing can wreak havoc on other parts too.
Depending on the specific cupping patterns, other things can also be wrong, but, 90 times out of 100, its the shocks.
What shocks/valving are you running?
http://www.quadratec.com/products/16...googlemerchant
JK Enthusiast
Joined: Apr 2009
Posts: 226
Likes: 0
From: Johnson City, TN
I noticed that my KM2's weren't wearing properly. For me it was simply tire pressure... In all honesty 30psi might be to high.
I chalk tested and retested about 27.5psi is where I drive with mine and they are wearing perfectly now.
I chalk tested and retested about 27.5psi is where I drive with mine and they are wearing perfectly now.
JK Junkie
Joined: Jul 2009
Posts: 2,343
Likes: 1
From: The San Andreas Fault
I don't believe the problem is tire pressure, 30 psi is not too much for a 4200+ lb curb weight. Look at the tire tire load information. I run mine at 35 psi in the winter with no problems.
If you have checked your tire balance, shocks and ball joints, then check your bearings. Any unbalanced, loose or faulty part that causes your tires to bounce will cause them to cup.
What is the backspacing of your wheels and are you using spacers?
BTW, this is not a general problem with KM2s.
If you have checked your tire balance, shocks and ball joints, then check your bearings. Any unbalanced, loose or faulty part that causes your tires to bounce will cause them to cup.
What is the backspacing of your wheels and are you using spacers?
BTW, this is not a general problem with KM2s.
JK Newbie
Joined: Dec 2007
Posts: 33
Likes: 0
From: Austin, Texas
I'm having the same problems with my KM2's. I run the tires at 35psi and have a TerraFlex 3" lift with TerraFlex shocks. After rotating the cupped tire to the rear, the problem is back again and it's always the front passenger side!