Cupped Tire Fix with a belt SANDER!

[svx_commuter]

I did not want to buy another set of tires. Some of the conti extreme contacts have cupped. So I took a belt sander to them. :D
Check the pictures in my locker.

[Earthworm]

yikes!!!!!

[SVXer95]

I'm speechless.

All I can say is:
Go buy new tires.

[Hohopirates]

Scary.....very scary. So were they over or underinflated?

Steve


P.S. Guys I was wondering....My car was leaking a little oil, but I fixed it. I put in straight 40 weight oil for a lawnmower...is this ok?

[SVXer95]

Scary.....very scary. So were they over or underinflated?

Steve


P.S. Guys I was wondering....My car was leaking a little oil, but I fixed it. I put in straight 40 weight oil for a lawnmower...is this ok?
THis is a joke, right?

[Hohopirates]

Do I look like I'm kidding? ;)

Steve

[svx_commuter]

THis is a joke, right?

No. It is not a joke.

[svx_commuter]

I'm speechless.

All I can say is:
Go buy new tires.

Yes I would like to buy new tires but I need the money for other repairs and I am pretty sure the new set will cup also sincel I didn't find the problem.

[svx_commuter]

Scary.....very scary. So were they over or underinflated?

Steve


P.S. Guys I was wondering....My car was leaking a little oil, but I fixed it. I put in straight 40 weight oil for a lawnmower...is this ok?

The air pressure does not appear to be the problem.

SAE 40 is non-detergent. It's better than no oil. I have had good results with Lucas oil additive. It takes a few oil changes to work its' way into the seals and parts.

[svx_commuter]

yikes!!!!!
That's it "yikes!!!!"
No comments about making flat spots?
Nothing about making the tire mis-shaped?
How about uneven sanding and wearing down the inside to the remove the cupping more than the outside that had less cupping?

I drove it today to work. :D
It was pretty good.
Nice and quiet again at 80mph,:D
Pulls every so slightly to the right :rolleyes:
And a very slight unbalance somewhere.

[n00b on demand]

What does tire cupping exactly mean?

[svx_commuter]

The tire cupping that I get is always on the inside 1/4 of the tire surface. The middle surface and outside surface of the tread has nothing.

It is a wear pattern that results in the outside diameter of the tire not being round.
The difference from the high spots to the low spots could be about 1/32 of an inch or less.
The distance from the one high spot to the next was about 2.5 inches on my tires.
There were about 28 high spots and low spots around my tires.

The net effect is similar to waves on the ocean when the tire runs down the road.
As the tire rotates each one of those little high spots hit the road and makes noise.
As the troughs get deeper the noise gets louder.

I also noticed when braking that the noise from the front tires gets louder as the troughs get deeper. This is most noticeable at low speeds right before the car stops.

The cupping can be seen if you know what to look for. It can also be felt with your fingers sliding over the surface of the tire.

[demonsvx]

I once used sawdust in a transmission to help with it slipping :rolleyes: Dont worry it wasnt a SVX :)

[SVXer95]

Have you ever replaced your struts? If they are not bad, it sounds like an alignment issue. Generally tire pressure will wear tires in one of three ways.

1) even.
2) on the outer edges (underinflation)
3) Inside (overinflation)

Tire pressure should not cause the tires to wear unevenly, just improperly. This is the case as long as pressures are even from side to side.

[THAWA]

You've got to be joking me.

[UniqueAngle]

Please tell me you're joking about sanding your tires. If you're serious though - go buy new ones. You're now driving on tires where the structural integrity is compromised. In English - you're just counting time until a tire failure/blow-out happens. Not smart!

[Beav]

Unless he sanded into the cords he hasn't compromised the structural integrity of the tire(s). No worse than tires worn from misalignment.

[svx_commuter]

Unless he sanded into the cords he hasn't compromised the structural integrity of the tire(s). No worse than tires worn from misalignment.

Hey Beav? Why do tires cup?

[SVX_MY_BABY]

I had all 4 tires cup on my car last year alaong with side wall cracking. The manufacturer replaced them under the warranty. Pro rated to tire wear.

[SVX_MY_BABY]

Why do tires cup?

Here is a link to why. Scroll down a bit.

http://www.babcox.com/editorial/tr/tr129622.htm

[svx_commuter]

Besides the info on cupping I found this....

"Some low profile tires (mostly performance tires), tend to develop uneven wear patterns because of their belt and tread design. As the tire rolls along, the deflection and squirming of the tread produces harmonics that cause certain areas of the tread or ribs to wear more than others. The wear pattern can be further compounded by other factors such as toe misalignment, wheel imbalance, wheel runout, underinflation or lack of rotation. After awhile, a "heel and toe" or "washboard" wear pattern may develop that generates annoying noise and vibrations at speeds above 40 mph. Once the wear pattern is established, it's too late to reverse it by rotating the tires. So the only cure you can recommend is to replace the tires and possibly switch to another brand or style that is less "quirky." "

.......and this more in-line with the wear I see on my tires. I think the term "cupping" applies to wear across the entire surface of the tire.

So, I get most of the wear on the side of the tire next to the engine. What way can I adjust the aligment to try for better tread wear? Less camber and more toe in?

[svx_commuter]

I was thinking about the Yoko AVS db I bought, used, from Jlittell. It was completely worn EVENLY across the width and all the way around. All the tires I ran became uneven at some point and one was a lot worse than the others.

I would like to know what he used for the alignment setting and for tire pressure.

[SVX_MY_BABY]

Aside from the cupping, my tire wear has been very even. My mechanic told me that Subaru Suspensions tend to work best with tires that have a rounded shoulder area (like Michelin Pilot) rather than a square shoulder like many of the newer tires. When I think of it. I ran my origional Potenza's until they were almost bald and they were even all over. They had a round shoulder. I've always had the dealer spec used for alignment, run a pound or two higher than the spec on the door and rotate every 7 - 8000 km.

[SVX_MY_BABY]

A bit off the topic, but speaking of tires with rounded shoulders; I would think that they would handle better. Last year in Formula One Michelin developed a tire which had a tread along the shoulder/sidewall area that became a contact point when the tire rolled under cornering stress. The FIA made them stop using it as it created an unfair advantage against the Bridgestone runners.