Tire Balance Question

Baja 252 · July 12, 2010

Well only 2500 miles and I picked up a screw in my RR tire. Took it to the tire store and the guy pulls of the tire and it has two wheel weights, 180 degrees apart on the inside of the wheel. Both factory weights, one small and one larger.

Makes no sense to me, why would the factory do that?

caddycruiser · July 13, 2010

Not unusual. Just how that wheel needed to be balanced originally. Every one is different.

pm26 · July 13, 2010

Placing more than one weight on one side of the tire is against common balancing rules (except when more than one weight is needed side by side). It is called weight stacking. However, it is occasionally done when the person doing the balancing is too lazy to remove the old weight.

In this case, they probably balanced the tire wrong first time, and then they rebalanced it by adding another weight without removing the old one.

caddycruiser · July 13, 2010

Placing more than one weight on one side of the tire is against common balancing rules (except when more than one weight is needed side by side). It is called weight stacking. However, it is occasionally done when the person doing the balancing is too lazy to remove the old weight.

In this case, they probably balanced the tire wrong first time, and then they rebalanced it by adding another weight without removing the old one.

True. Coming from the factory like that, not unlikely. Things are balanced but not guaranteed perfectly, given production levels & variations in tires and wheels.

CapitalTruck · July 13, 2010

I strongly recommend that you find a Hunter Road Force balancer. www.gsp9700.com to find one. They really are the best way to balance a tire (in my uneducated opinion).

ColoradoSkiCountry · July 13, 2010

A digital balance machine is a digital balance machine. They all do the same things with the same results. They are only as good as the idiots using them. (tire shop people)

Irv · July 14, 2010

Just had my tires re-balanced again, first time was an out of round front passenger side Good-Year (20")

Truck tires were still out of balance when it went in last week for the fuel pump sending unit replacement and washer recall so they did them again.

This time when I got my truck back I noticed all the ugly outside factory weights were removed and inside weights were installed front and rear (the way they should have come from the factory!)

Truck finally rolls down the Hwy without any vibration what so ever!

ddp1960 · July 14, 2010

Why does the factory put clip on weights on the outside of the rim? This marks the rim and causes further white marks and corrosion on the rim. Is everyone seeing this also?

Doug

[email protected] · July 14, 2010

Placing more than one weight on one side of the tire is against common balancing rules (except when more than one weight is needed side by side). It is called weight stacking. However, it is occasionally done when the person doing the balancing is too lazy to remove the old weight.

In this case, they probably balanced the tire wrong first time, and then they rebalanced it by adding another weight without removing the old one.

I'll have to respectfully disagree with that.

Wheel/Tire combinations are balanced today by the digital balancing machines in more than one plane.

The primary balance is in the rolling plane first. This keeps the tire from throwing itself in an up/down motion. The wheel/tire combination is then balanced in the secondary plane - where an out of balance condition side to side can cause the assembly to wobble side to side.

The digital balancing machines show the operator exactly where to place the required weight the first time, then the wheel/tire is spun a second time and the machine shows the operator where to place the second weight if it is needed.

The first weight most likely is the larger of the two you see, and it most likely was put there to balance the tire in its rolling plane. The second weight was most likely put there to correct a smaller out of balance condition - to correct a possible side to side wobble.

Truck tires and wheels are large and heavy - it is quite frankly an amazing piece of manufacturing quality control that produces such near perfect tires today.

The weights are not there to get a blem out the door - the Factory doesn't buy nor use blems. They get sold to retail dealers.

FWIW,

Carl B.

[email protected] · July 14, 2010

Why does the factory put clip on weights on the outside of the rim?

Depending on the diameter and width of the wheel and thus the tire size... If an out of balance condition exists in the primary or rolling plane, that requires more than X ounces to correct - the weight should be split, with half placed on the outside of the rim and the other half on the inside. "X" could be as little as four ounces for one size tire, or 2X for others..usually "X" is four to six ounces.

If you put four or more onces on one side of the rim, to correct an out of balance condition in the rolling plane - you can then cause an out of balance condition in the secondary or side-to-side plane.

Keep in mind that as the tread of a spinning tire meets the road - a squirm is created, and that can be either mitigated by a properly balanced tire - or made worse by a tire that is out of balance side-to-side to begin with.

Personally - I'd rather have a small weight on the outside of the wheel - than have a tire out of balance. One option is to use stick on weights place close to the centerline of the wheel. However balancing the wheel/tire in both planes using stick on weights - may require placing the weights in one position to balance the tire in the primary plane - then having to move them in/out from the center line to gain a balance in the secondary plane - this takes a lot of trial and error and a lot of time to do properly - not to mention having a clean surface on the inside of the wheel.

FWIW,

Carl b.

Baja 252 · July 14, 2010

Why does the factory put clip on weights on the outside of the rim?

Depending on the diameter and width of the wheel and thus the tire size... If an out of balance condition exists in the primary or rolling plane, that requires more than X ounces to correct - the weight should be split, with half placed on the outside of the rim and the other half on the inside. "X" could be as little as four ounces for one size tire, or 2X for others..usually "X" is four to six ounces.

If you put four or more onces on one side of the rim, to correct an out of balance condition in the rolling plane - you can then cause an out of balance condition in the secondary or side-to-side plane.

Keep in mind that as the tread of a spinning tire meets the road - a squirm is created, and that can be either mitigated by a properly balanced tire - or made worse by a tire that is out of balance side-to-side to begin with.

Personally - I'd rather have a small weight on the outside of the wheel - than have a tire out of balance. One option is to use stick on weights place close to the centerline of the wheel. However balancing the wheel/tire in both planes using stick on weights - may require placing the weights in one position to balance the tire in the primary plane - then having to move them in/out from the center line to gain a balance in the secondary plane - this takes a lot of trial and error and a lot of time to do properly - not to mention having a clean surface on the inside of the wheel.

FWIW,

Carl b.

Thanks Carl for the explanation, that's the information I was looking for. I didn't think it wasn't a mistake. I remember the video that came with my Z06 showed when they balance the tires they spin them several times, now I know why.