Hunter Smartweight Technology?

[The Critic]

http://www.weightsaver.com/VIDEO/index.htm

Is their weight saving technology a good thing for customers, or is it simply a way of saving money for shops at the expense of a less than perfect balance? The video talks a lot about small vibrations being unnoticeable...

Thoughts?

 

[JHZR2]

Got to "run the experiment" to know for sure... like yopu said in the other thread, could depend upon the tire/aspect ratio if it makes sense...

 

[The Critic]

Originally Posted By: JHZR2
Got to "run the experiment" to know for sure...

They run an experiment during the last few minutes of the video.

I wonder what CapriRacer and others in the field have to say about this.

 

[JHZR2]

Originally Posted By: The Critic
Originally Posted By: JHZR2
Got to "run the experiment" to know for sure...

They run an experiment during the last few minutes of the video.

I wonder what CapriRacer and others in the field have to say about this.


I mean a user needs to do it on their car and see if any differences are actually perceivable...

 

[The Critic]

The high-volume America's Tire centers have one of these Smartweight balancers IIRC, but I'm sure they have one because they can afford it:

http://www.psedealerequipment.com/node/201397

At nearly 10k, it is quite an expensive balancer. Weight savings aside, I wonder if there is a difference in the accuracy of a wheel balance with these higher-end Hunter dynamic balancers in comparison to the ancient Coats machines.

 

[firefighter]

We have a hunter roadforce machine with the smartweight program. It is awesome, it stops weight hunting. We do tires for this one company they are 20's or 22's really low profile on ford and chevy trucks. When they have a vibration problem they send them to us. Before we had the smart weight technology, you would balance a tire, then when you did the check spin it would want another 1/4 or 1/2 oz elswhere, it was very annoying. With the smart weight technology , it really calculates it out with less weight and no more weight hunting. People are always happy with our balance jobs. So to answer the question yes it does save the shop $ through less weights, but it is a much more precise balance

 

[CapriRacer]

Originally Posted By: The Critic
........I wonder what CapriRacer ...... (has) to say about this.


This is all about tolerances.

Balance weights come in increments of 1/4 ounce or 5 grams - unless you are using tape-weights, which you can cut into smaller pieces. Most vehicles are insensitive to static imbalances under 1/2 ounce. So balancing to within 1/4 ounce is a bit of overkill.

Vehicles are more sensitive to static imbalance than dynamic imbalance. That means you don't need to use as much weight to get an acceptable level of dynamic balance - meaning that using 1/4 oz increments for dynamic is a lot of overkill.

All this system is doing is using different tolerances for static and dynamic imbalance. The net effect is that less weight is used.

 

[The Critic]

Originally Posted By: CapriRacer
Most vehicles are insensitive to static imbalances under 1/2 ounce. So balancing to within 1/4 ounce is a bit of overkill.

Vehicles are more sensitive to static imbalance than dynamic imbalance. That means you don't need to use as much weight to get an acceptable level of dynamic balance - meaning that using 1/4 oz increments for dynamic is a lot of overkill.

Thanks for the insight.

Here's my concern. After reading your reply and watching the video again, it appears the Hunter software is reducing the static and couple imbalances to levels just below tolerance, with more emphasis placed on static imbalances.

Considering that tires do go out of balance eventually, wouldn't tires balanced using the SmartWeight feature go out of balance far more quickly than ones balanced using a traditional balancer? It sounds like the Smartweight feature is doing "just enough," and the tires will pass the limits for static and couple imbalances much faster than a tire that was balanced to stricter tolerances.

Please correct me if I am wrong?

Thanks.

 

[CapriRacer]

Critic,

I am of the opinion that tires go "out of balance" much more slowly than is normally thought. Put a different way, I don't think that tires wear unevenly (the source of the additional imbalance) fast enough to worry about - EXCEPT - where there is an alignment problem and that is going to cause additional imbalance regardless of of how closely the initial balance is to perfection.

I don't see any issues with the way Hunter is using the system.

 

[eljefino]

With two saturns running self-static-balanced tires, I run into some that behave themselves on the rear but shake the steering wheel up front. Eventually I had to take a known dud into walmart for their $5 one-time balance.

IDK what machine they use but the tire came back with one ugly big .75 oz weight; I think WM is done with lead. It behaves itself on the front now.

 

[PandaBear]

IMO the main saving is not in the weight, but the labor to balance again after the first weight and the skill a technician need to run the machine.

How much is the older type of machine?

 

[AstroTurf]

Be Careful of what they say is imperceptible to the customer.
It is perceived by the tire, the vehicle suspension, and ultimately, Your Mpg.
Have your tires zero balanced. Frequently, every day, every time you drive. Use Dyna Beads by www.Innovativebalancing.com

I do and my tire wear and Mpgs thank me for it.

Just my Two Cents, Jim

 

[Rand]

I used dynabeads IMO they are overrated and dont work well in low profile and smaller car tires.

in larger suv/ fullsize truck or semi tires they work much better.

If you have any moisture in your tire they tend to clump and freeze in the winter for a few miles also.

 

[Ken2]

Many states are outlawing lead wheel weights. They fall off and get ground into lead dust on the road, then the lead dust washes into soil and water poisoning it.

The non-lead weights are bigger and uglier than lead weights...I don't know how the cost compares. Any balancer what reduces the size and number of weights will save in several ways.

Dynabeads says on their web site that they do not work well in low profile tires, and they don't recommend them for tires of less than a 75 aspect ratio except maybe for a fine tune of the balancing. Water and oil from the compressed air is a problem.

 

[AstroTurf]

Originally Posted By: Rand
I used dynabeads IMO they are overrated and dont work well in low profile and smaller car tires.

in larger suv/ fullsize truck or semi tires they work much better.

If you have any moisture in your tire they tend to clump and freeze in the winter for a few miles also.


Did you use the beads with or without the existing balance lead weights?

Thanks, Jim

 

[Shannow]

Originally Posted By: The Critic
I wonder if there is a difference in the accuracy of a wheel balance with these higher-end Hunter dynamic balancers in comparison to the ancient Coats machines.


Critic, they are saying that they are targeting a lesser accuracy of balance when measured according to the old method, by defining a new method which uses the tyre/wheel assembly as part of the equation.

The old method works to "ounces" of unbalance, which isn't a metric generally used in industry, where the actual displacement is measured.

As an example, turbines. Shaft vibration amplitude is measured. Anything under 80um shaft movement is pretty well OK, regardless of it being a 40 tonne main turbine rotor, or a 4 tonne auxilliary turbine. If either got to around 100um, we'd look at balancing to get them back under 80, preferrably in the 50s.

The big rotor, we balance with weights in increments of 2/3lb, The small one in tens of grammes...but remember our target is actual running smoothness rather than getting within half an ounce of the "perfect" balance.

IMO, it's kosher, in answering the actual question of tyre/wheel vibration.

All that being said, if the old method gave a more "accurate" balance, and there was no savings as a customer with the new method, I'd take the old.

 

[CapriRacer]

Just a bit more clarification.

The company I work for has done many vehicle sensitivity experiments aiming towards helping the vehicle manufacturer determine if their vehicle has any excessive sensivity to tire and wheel related issues.

You can balance a tire and wheel assembly to within a very tight tolerance. For those who don't know, most balance machines round off the weight needed to either 1/4 oz, or 5 grams - and you can set the machine up either way. But you can also turn off the rounding feature and get the imbalance stated as accurately as the machine allows. Needless to say, this is over-overkill - but it can still be done.

We sometimes do this when we are interested in the determining the actual imbalance of returned tires. The wheel is "zero balanced", so any residual imblance is 100% the tire.

OK, back to the vehicle sensitivity studies. We take a set of "zero imbalance" / "zero runout" tire and wheel assemblies and apply that to the car and run a baseline ride. Hopefully, there will be no "shake" - the term we use to describe vibrations caused by tires and wheels.

Because we know the mathematical relationship between runout and imbalance, we apply a weight (I forget how much) to one of the wheels and do the ride again. This is repeated - and again I forget the exact procedure - and then all that data is plugged into a computer to determine the sensitivity of the vehicle to static and dynamic imbalance (or its functional equivalent, radial run out and lateral runout) - Oh and I forgot to mention we rate the ride quality on a scale of 1 to 10, so that is the input data to the computer

We have always found that vehicles are much more sensitive to static imbalance (radial runout) than dynamic imbalance (lateral runout). The Hunter Smartweight technology is just taking advantage of that.

 

[bdcardinal]

Originally Posted By: CapriRacer
We have always found that vehicles are much more sensitive to static imbalance (radial runout) than dynamic imbalance (lateral runout). The Hunter Smartweight technology is just taking advantage of that.


Is there any correlation between suspension design and sensitivity to imbalance that you have seen? Like in a RWD applicaion would a front Macphearson Strut vs SLA 1 or SLA 2. Or having IRS or live axle with either a 3 or 4 link and a panhard bar or watts link have any differences?

 

[CapriRacer]

Originally Posted By: bdcardinal
Is there any correlation between suspension design and sensitivity to imbalance that you have seen? Like in a RWD applicaion would a front Macphearson Strut vs SLA 1 or SLA 2. Or having IRS or live axle with either a 3 or 4 link and a panhard bar or watts link have any differences?


I don't know. If there was, it wasn't communicated to me.

But an educated guess, is "No!". What I remember about sensitvity was it had more to do with the resonant frequency of the chassis. Some chassis's had a mode near the resonant frequency of the suspension - the wheel hop fequency.