The art of tire balancing?

[SCadaddle]

So my recently new to me 05 Subaru Legacy wagon @85k miles has a set of fairly decent Uniroyal Tiger Paw tires that the previous owner fitted. The car does pretty well up to about 65mph, but above that think space shuttle re-entry phase. I'm thinking of having the tire balance checked. That's when I notice on a couple of the wheels, there is a weight at one spot and yet another weight say 120 degrees around the wheel.

I've never seen such. So I take the car to one of these new boutique tire joints after finding a coupon on the www. "Tire balance and rotation---$29.99". Sounds reasonable enough to me. Get to the place and it's a millennial running the front counter. Ask him about the multiple tire weights in different spots on the wheel as I draw him a sketch. Ask him if he's ever seen that. "Sure do, all the time. We put the weights on the wheels where the computer tells us to." Hrrrumphh. I'm still not believing this correct, but I tell him that I might go for the balancing but not the rotation part of the deal. Well, that would be a different price. Huh? Yep, $29.99 to rotate and balance, $15 per wheel just to balance. Well now, that makes a lot of sense doesn't it?! I'm willing to pay your price for 1/2 of the service but for that it's going to cost me twice as much? As I hear the one guy working on a car in the bay hammering away relentlessly with the impact gun, I ask him about proper torque when mounting the wheels. Not a problem. We just had a class on that last week! Ok, so (looking at 4 people in the waiting room and noticing another technician behind the counter playing with his cell phone) about how long before you can get to me? About an hour.......ok, well, I got stuff to do. I'll see if I can get back on Monday. (But don't count on it!)

Am I in the dark ages when it comes to balancing a wheel and tire or what?!

[fastfredracing]

They don't always balance up the first time, and it will tell you where to put the next weight. If you want to , you can remove the weight, and start over, and may be able to get it to balance up with just one weight by shifting its location around, but sometimes it does take more than one weight. This usually happens on large wheels where there is a lot of imbalance, or if there is some irregularity in the tire, or rim.
Modern tires and wheels are huge compared to how they were 20 years ago. Ive had some truck wheels and tires take up to 3 or more ounces on each plane to get them to balance out . That is about 6 inches of weights . I try to never to do two weights on the outside , because. personally , I think it looks ugly but on the inside of the rim, who cares ?

[Sooner or later]

Could be a couple of things.

Balanced once and when they checked a second time it required the second, smaller, weight.

Could be a dynamic balance where they put both weights on the same side. True dynamic balance requires weights to be placed on both inside and outside of the wheel.

Or a screwed up machine or tech.

[masraum]

Most of the folks that balance these days are min wage morons that don't care.

I've heard that if you get a wonky tire and/or wheel, that sometimes it can help to pop the tire beads, rotate the tire a little bit and start over, but most places (especially when they're charging $29.99) aren't going to go that extra mile.

I do believe that you may have to put weights in multiple locations to get the tire to balance.

If you want a really good balance, at least as of a few years ago, the best balancer was supposed to be the Hunter 9700 Road Force Balancer or something like that. I think TireRack.com had a way that you could search for places near you with that kind of balancer. Things may have changed since then, but I doubt it.

[SCadaddle]

I've always subscribed to the "red dot-yellow dot" placement of the tire on the wheel since the manufacturers have been putting the dots on the tires, yet I have never found a tire tech that had any clue as to the dots. In one instance, with a directional type tire stating "outside" on one sidewall and the dots on the inside sidewall, the tech, after being clued into the dot system by myself, scratched his head and brought the tire to me outside the service bay and asked how to handle that situation. I said give me a piece of chalk.....then drew a line up the sidewall, over the tread and down the other sidewall and put a X. There you go. This is pretty basic stuff. Maybe I'm asking too much of the industry?

I've also had them break the bead and rotate the tire to another spot if the weight was excessive. We're talking 14-16 inch car tires here. Not a monster mudder on a pick up truck! I guess at some point, the labor costs might exceed the cost of the balancing weights, and probably 95% of the customers are either clueless or could care less.

[Sooner or later]

A vibration can be caused by more than just static or dynamic balance.

Radial and it's harmonics. Think out of round (high harmonicvalue) or a more localized high/low spot due to, say, a heavy tread splice (low harmonic)

Lateral and it'"s harmonics. Think a tread and belt package that is applied in a snake pattern(high harmonic) or a belt spice that has a large offset (low harmonic)


All the weights in the world wont correct for radial or lateral.

[Don Ro]

Agreed, morons tend to gravitate to mounting/balancing tires.
.
Goodle "Tire Truing" in your area...
Mount & balance, drive a couple of hundred miles, then have them true the tire...where they mount it in a machine that actually slices off the high side of the tread.
The company's owner that did that to my tires for years said the most Michelin tires didn't need truing.
.
BTW, new tires on my Ducati MH900e...took them to the hot shot Duc. dealer and the goon put a huge strip of lead weights on the rear. I looked at it and mentioned it...service manager asked if I wanted them to do it over...I just walked out.
Any moron would break the bead and rotate the tire 180'.

[Arizona_928]

^^
I have had a set of hmmwv tires balanced. A good 8x2 inch strip of peel on weights. I think I got my $$ worth (30 bucks a tire)...

[Mark Henry]

My wifes snow tires I mounted them with no weights. 4 oz of airsoft pellets in each tire.
Works perfectly but the rub is it doesn't work well in wide tires.

My buddy had tires that they just couldn't get a slight shimmy out of, so since they were balanced we tossed 2 oz of pellets into it, fixed it right up.

In order to use the airsoft pellets you have to break the bead to get them in, there is a commercial version that you install through the valve stem.

[javadog]

You should only have weights in a maximum of two spots and never two spots on the same side. If you do have weights in two spots on the same side, you need to find a more knowledgeable tire shop

[asphaltgambler]

I know this may sound obvious but more often than not the wheel has either a tweak laterally or the rim that has flattened in an area from potholes. Most of the wheel service 'joints' as said above have kids paid minimum wages doing the work. They almost never see the rim damage unless it is very bad. Same if the tire is out of round. All tires even new ones have some out of roundness.

My observation is the Michelin and Continental brands have the least issue with that when new and tend to keep their roundness throughout their life.

Tire 'shaving' or 'sipping' is performed on a machine which resembles a tire balancer and with a skilled tech can do wonders without taking too much tread off. You cannot believe how smooth a vehicle can ride and drive with this done. Problem is most places make more profit from selling new tires VS making your current tires round.

Like anything else, it's overly simple to pit weights where the 'cornputer' indicates they need to go, but another to have a good eye for a small rim and tire issue.

[Mike80911]

As already mentioned a road force balancer is the way to go.
Do you feel the vibration in the steering wheel or in the seat? If it is in the steering it would indicate a problem in the front wheels and in the seat would indicate the rear wheels are the issue. Most places today place all of the weights on the inside of the wheel instead of inside and out. With the outer weights being as close to the outside as they can get them.
Tires and wheels have heavy spots and sometimes when mounted those spots line up causing the need for a large amount of weight to be added when balancing. Most tire installers do not know that when that happens you simply break the bead and rotate the tire 180 degrees and re-balance and that usually corrects the issue.

[SCadaddle]

Here are the front wheels on my Subaru. One of the rears has a single weight on the outside of the wheel and the other has no weights on the outside of the wheel. Haven't investigated the backsides of the wheels for weights on them.

As for the Hunter Road Force Balancing, the plant that manufacturers them is about a 30 minute drive from my home. I just might swing by there and see if they would like to entertain some tech talk.

[Sooner or later]

That is just wrong.

[john70t]

^Too much lead weight.

The rim is not formed perfectly.
The tire is not formed perfectly.
But when matched together they should be close to perfect.

[Don Ro]

I have a Marc Parnes moto wheel balancer. Put two milk crates on end and balance in between.
A penny weighs 3 grams, I've cut one in half and after balancing a moto wheel/tire, placed the cut penny on the rim with double sided scotch tape and watched the wheel rotate.
I wish there was a simple one like this for auto wheels. There must be.
.
Motorcycle Wheel Balancer

[Jeff Alton]

Most good balancers (regardless of what company made them) have a program to show how to rotate the tire to minimize weight, and match the high and low run out of the tire/wheel assembly.

We have twice this year balanced an assembly that required no weight. New tires and new wheels in both cases, one red dot and one yellow dot. No vibration up to 250km/h reported... (not that we tested it at those speeds)

As to the above, if a tire has a flat spot or feathering from a poor alignment, or the wheel has radial or axial runnout it may take a second weight placement on one of the planes to get to zero. Most vehicles will not transmit any vibration with a misbalance of .25oz/7gm

There is a fair amount of weight on the wheels shown in the picture. I think they did not start from scratch but balanced with weights left on the wheel from the previous balance....

[manbridge 74]

Road force balance
Force matching
Straight wheels
Non out of round tires (you can balance a stop sign but it won't feel great)
Uniroyal tires aren't that great

[RKDinOKC]

My tire tech uses a Hunter Road Force balancer.

He does this...
Spin all the rims empty. The balancer tracks each one and he gives the balancer a reference position for the wheel, usually the valve stem so he can place it back on the balancer and the balancer knows it's orientation. Then mounts the tires on the rims, puts the wheels on the balancer with the rim in it's referenced position in relation to the balancer. Then spins em up. It tracks each tire and you mark a reference position on each tire as well. After all four have been spun the balancer recommends which tire to mount on which wheel and how the positions should be located to each other. After remounting the tires to the correct wheels and in the right position, you spin them all again adding the weights where needed as necessary. This way it best matches the rim to the tire to use the least weight to get the best balance.

As a true road force balancer it takes into consideration the weight of the car and the max speed you are expecting to drive the car and it will make sure they are balanced for that speed as well. It also checks for roundness and trueness of the wheels and tires and will reject any rim or tire that is too far off or takes too much weight to balance or can't be shaved round for the speeds desired.

Most all the work is done by the balancer. But the operator does have to pay attention and be willing to swap the tires around to different rims after having already mounting them once.

Only had one set he mounted that I ever had any problems with. I had replaced the plastic valve stem caps with some aluminum ones that had logos on them. It caused a slight vibration from 80mph to 85mph. Had to rebalance the wheels with the fancy valve stem caps on them to get rid of the vibration.

[Bill Douglas]

Richard your tire tech sounds like he knows what he's doing.

A mechanic friend told me a lot of tires these days are manufactured WAY out of balance - cheap manufacturing I guess. And the guys at the tire places pick out the best ones for themselves and their favored clients.