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benmunger
12-29-2003, 09:16 PM
i have a 1.5 " drop with no camber kit. I have been ridding on these tires for about 14,000 miles now.


I researched it and have come to 5 answers on what causes cupping.
1. alignment
2. blown struts (It's not this, i checked my struts)
3. wheel bearings worn (Its not this)
4. excessive tire or wheel runout.
5. worn balljoints (its not this)

questions
a. What is "wheel or tire runout"?
b. If its alignment (camber), will a camber kit fix it? Or can i just get away with regular alignment at any old alignment shop?
c. Does any one have cupping problems on the rear wheels, under these same conditions?

Vertigo
12-30-2003, 05:00 AM
What is that tread wear rating on your tires?
Wheel and tire runout is where the tire rolls strait and true with the wheel. You see this when you balance them. As you balance them, you look for hoping and tread going side to side.
Majority of premature tire wear issues are due to alignment. IE; camber, caster and toe. Also, tire pressure plays an important factor in how the tire wears.

31102si
12-30-2003, 05:46 AM
anytime you lower a car you throw the camber and alignment off,you need a rear camber kit and have the car aligned and balanced. you have probably already ruined those tires though.:confused:

chunky
12-30-2003, 07:53 PM
Originally posted by benmunger
i have a 1.5 " drop with no camber kit. I have been ridding on these tires for about 14,000 miles now.


I researched it and have come to 5 answers on what causes cupping.
1. alignment
2. blown struts (It's not this, i checked my struts)
3. wheel bearings worn (Its not this)
4. excessive tire or wheel runout.
5. worn balljoints (its not this)

questions
a. What is "wheel or tire runout"?
b. If its alignment (camber), will a camber kit fix it? Or can i just get away with regular alignment at any old alignment shop?
c. Does any one have cupping problems on the rear wheels, under these same conditions?

a) wheel runout = the uniformity of the wheel. the edge of the wheel should be X mm from the center of the wheel at every point around the rim. However, b/c nothing is perfect you won't find a wheel that has zero variance from point to point around the edge of the wheel. The maximum runout specifies the maximum variance between the highest & lowest distance from the hub. Basically, if you have shitty wheels, then the runout may be relatively high, causing the wheel to oscillate at higher speeds. A wheel that is severly out of balance will also cause cupping.

b) if it's alignment, the cupping is probably not caused by camber, it's probably caused by toe irregularities. Camber will cause uneven wear on the inside v.s. outside of the tire, but will not cause cupping. If the cupping is occuring only on the inside or outside of the wheel, then it's almost certainly a toe related issue. If the cupping was across the entire width of the tire, then it's probably a wheel bearing/loose suspension component/wheel runout/etc. issue.

c) i never had any issues, of course, I got my car aligned immediately after I lowered it and have had it algined periodically since.