Road Force Balance

Joined
May 25, 2005
Messages
15,636
Location
ROCHESTER, NY
Bought new Pirelli Cinturato P7 A/S+ from TR at the end of February and had them installed locally(at our largest tire store in the Rochester, Buffalo, Niagara Falls area) in early March. From the beginning, the tires were all out of balance. I rotated all of the tires(one side at a time) to determine which tires may be the culprit and it was all 4, IMO.

Brought the car back for a re-balance and...
...The original installer said that all 4 tires were out on the inside portion of the wheels(OOPS!) and in only 3 weeks/
I told the shop that the tires were out of balance right from the beginning on the hiwy and I had already moved all tires around the vehicle. After the rebalance, the tires were only slightly better but they were not where they should be. Still shimmying.

I found a local guy who ONLY travels(you can't go to him) and installs tire, brakes, RFB, right on his truck in your driveway. He came out to my house and did a RFB on all 4 tire(1 tire had to be turned ~1/4 turn on the wheel for a road force match/RFM). But, all is now perfect.

He claimed that the tire shop that installed my tires only did a static balance not a dynamic balance(which would have been better).

This traveling tire guy ONLY does RFB with all of his tire installations. The Hunter GPS 9700 RFB is his only balancer. You can buy your own tires or get the tires from him. He uses 4-5 different local tire distributors. He allowed me to come up into his truck while he explained everything to me(as if I were in training) while he did the RFB/RFM.

Very Cool,

CB
 
Last edited:
I discovered the Road Force Balance (RFB) method, after replacing two front tires on my '06 Spec V.

I bought the two tires (quality Yokohama Avid Ascend GTs at that) from a major tire chain. The second re-balance was a little better, but not like it should be. My attempt to have it done a third time, was hindered by one of the service managers, claiming that the irregularity wasn't tire based and that I should leave the car with him to further diagnose.

I proceeded to get in touch with the corporate office of this chain. I expressed my displeasure with the way the service manger handled my third attempt at resolving the issue at hand. A training rep got back to me, saying their machines don't do RFB, which she termed as "speed balancing". She said that the tire service would cover the cost for the RFB, which they did.

After some research which also included contacting Hunter, I discovered that in my neck of woods, a number of venues offer RFB. The prices vary. For my two tires, I paid around $41 dollars taxes included. The RFB dramatically improved the driving experience.

In addition to the prices varying for such work, it's important to use someone proficient in doing RFB. An RFB can be improperly done.

There's a good deal of info on RFB:

https://www.youtube.com/results?search_query=road+force+balance
 
Last edited:
In my area, RFB is ~ $15/tire as it was with this traveling tire guy providing a tire(s) don't have to be repositioned.
He also charged an additional $15 to break the bead of the tire/wheel and reposition the tire and again, RFB.
So, he does spend quite a bit time measuring the wheel/tire combo to make sure they're in spec and is first OK to RFB.

Like I mentioned, 1 tire needed to be turned 1/4 turn on the wheel. This included...

RF measurement(which he did with all 4 tires/wheels)
Remove air & Break bead
Rotate tire 1/4 turn
Reinflate
Put back on the RF machine
Measure again
re-RFB
$15 extra

So with tax, it was $81 in which, the TR will reimburse me some or all of this. I have it in writing from them.
 
Yes, it was explained to me that depending on what the machine communicates, some additional work might be required for an additional cost.
 
Timely subject for me.

I test-drove a 2016 4Runner Trail Premium yesterday (manual transfer case! crawl control! fun fun) and it was flawless, EXCEPT for a shimmy between 40 and 70. Not horrible and 90% of drivers wouldn't care one bit. But I do.
The tires were so new that they still had blue on the white lettering (facing inwards). I figured it was a quick spin-balance.

I talked with the two salespeople that were helping me, and asked if their main (new car) dealership offers dynamic/road force balancing to fix this problem. He said he wasn't sure, but that he would get that answer for me on Monday. Worst case, I'll buy it and bring it back here to have it fixed.

I believe RFB is the only proper way to balance tires and wheels after years of having shoddy work done at places that don't offer it.
 
Maybe this can clear up some of the mystery and misunderstanding on balancing because balancing is balancing whether its a solid rotor mass in a turbine or spinning a doughnut on a broomstick. There is no such thing as perfect universal balance because as forces change- bodies react differently so balance is defined by a range, not a state. Its basic calculation is an L/D over run method. ( but there are others)

As a PE and CAT-IV doing motion diagnostics and modal analysis, this is a common discussion to tell clients and I often use the car as an example they can relate to.

In the most basic term, "balance" defined as the relationship between center of mass and center of geometry and the criticality is mostly determined by RPM.

Lets assume a proper tire/rim installation and a calibrated balancing machine for the following.

In terms of auto terms you would be best to understand that these are simply more "precise' methods of balancing- not "better' per se. Which level solves the problem is adequate.

Static- think bubble balancer. This is simple mass to axis and weights (added or removed) bring it close to center.

Dynamic- the body is in motion. It internally adjusts to the given RPM. You can also have external forces but only those forces generated by the body as it reacts to its immediate environment. ( most commonly used method)

Then you have calculated loading ( real or modeled) which is the RFB in the car world. This puts physical stress on the rotor mass as it would experience in operation. This identifies ( exposes) things the other methods cannot. The accuracy is dependent on the load mimicking actual conditions.

Even then ( and over time) as the rotor mass changes ( erodes, changes geometry, changes RPM of forces change)- the balance will change as well as that center mass/geometry changes.

Putting weight on one or both sides ( assuming the machine is calibrated) is the same as far as mass goes.

Then theres troubleshooting- to a degree minor shaft deflections, densities and so forth can be "covered' by a balancing standard and not "felt" ( except on the accelerometer0 they are still there and inducing change which will eventually surface and cause wear/damage.

Just FYI
 
I'm glad things can be resolved but is it not galling as heck that there are BOZOS in the tire business who cannot balance a tire.

This thread reminds me to contact my local RFB guy. Last time we spoke his Hunter machine was on the fritz.
 
I had a similar experience with DT a few years ago, where brand new tires shimmied. After four return trips they said the tires are bad and replaced them. I suspected user error but went with their suggestion. Second set also required 3+ balances until I finally took them to a real installer with RFB. One and done.

On a positive note, a new DT was just built near me and they did a great job balancing a problematic tire that is near the end of life. The balance is only as good as the person doing the work, regardless of whether they RFB or not.
 
Char, sorry if I missed it, but what vehicle was this on? Did you ever have tire balancing issues on this particular vehicle before?
 
Last edited:
When compared to previous years, I'm sensing that there're:

- more tires on the market, which aren't as easy to balance
- cars are generally lasting longer, with greater miles put on them
- as cars age with increased wear, quirks can develop that might make balancing more difficult
- cars are being made with some greater intricacies, which might make balancing a harder process to perfect
- a good number of tire venues might be experiencing a greater employee turnover, leading to some not so experienced installers
- a growing number of consumers are perfectionists.
 
Last edited:
Originally Posted by Bogdon
When compared to previous years, I'm sensing that there're:

- more tires on the market, which aren't as easy to balance
- cars are generally lasting longer, with greater miles put on them
- as cars age with increased wear, quirks can develop that might make balancing more difficult
- cars are being made with some greater intricacies, which might make balancing a harder process to perfect

- a good number of tire venues might be experiencing a greater employee turnover, leading to some not so experienced installers
- a growing number of consumers are perfectionists.


Very well thought out list and I believe those highlighted are probably the main drivers.

I might add 2 more.

- The drive to make cars more "precision" and efficient especially in areas of weight and aerodynamics, this has 'exposed' different degrees of "felt" vibrations that probably have always been there but were previously absorbed into the mass and camouflaged. (cars have always had some chronic vibration issues)

- Possible the introduction of "new technology" to the market as a service to increase revenue. Understanding the need for load defined balancing is as old as the technology itself but somebody decided to add a pressure roll to a spin balancer only in the last few years. This is hardly a discovery of something "new".
 
Our local dealer has a road force machine but sadly he has never has an employee that has the slightest idea what he is trying to accomplish with all that technology.
 
Yep, been there done that. A balance job is only as good as the tech doing it.

Glad you're riding smooth again
19.gif
 
Road Force Balancing isn't just about balance. It is also about measuring and, perhaps, correcting tire and wheel uniformity (Think out-of-round and you'll be close!)

Uniformity and balance are completely separate items. Balance is about mass distribution, where uniformity is mostly about "Roundness".

And - YES! - tires and wheels on new cars have had uniformity specs since at least the mid 1980's. When did it start? Unclear, but the late 1970's might be a good guess.

Currently EVERY car manufacturer specifies the limits for tire and wheel uniformity.

One of the current issues is that a lot of work has been done to make car chassis' stiffer. Sometimes that results in a chassis whose resonant frequency is near the frequency of tire rotation - and the result is a sensitive vehicle. There were several GM cars who had this problem.

Tire manufacturers have very expensive machines to measure tire uniformity (On the order of a million bucks each!) These are highly accurate, repeatable, and fast! Some tire manufacturers measure 100% of their production, some don't!

Hunter engineering produces a line of shop level machines that aren't as good, but do give adequate results. The problem is that the Hunter machines can give both false positive and false negative results. (false positive being measures good, but is actually bad, and false negative is the opposite!)
 
Originally Posted by JTK
Char, sorry if I missed it, but what vehicle was this on? Did you ever have tire balancing issues on this particular vehicle before?


It's the Altima in my signature.
Prior to having the Pirelli's installed, I had(on the same wheels), Michelin Primacy MXV4 that were perfect(but worn out). And I also have separate Winter wheels & tires, which were also perfect as well during this recent winter.

You know which tire dealer I'm talking about. They're name is smeared on every Buffalo Bills backdrop during TV interviews.
 
Last edited:
Originally Posted by Kira
I'm glad things can be resolved but is it not galling as heck that there are BOZOS in the tire business who cannot balance a tire.

This thread reminds me to contact my local RFB guy. Last time we spoke his Hunter machine was on the fritz.


If you're referring to my last post, it is the FIRESTONE Service Center in my area who's RFB is on the fritz, not the guy who came to my home. Unless you're referring to they guy in your area???
 
Last edited:
Originally Posted by Chris Meutsch
Timely subject for me.

I test-drove a 2016 4Runner Trail Premium yesterday (manual transfer case! crawl control! fun fun) and it was flawless, EXCEPT for a shimmy between 40 and 70. Not horrible and 90% of drivers wouldn't care one bit. But I do.
The tires were so new that they still had blue on the white lettering (facing inwards). I figured it was a quick spin-balance.

I talked with the two salespeople that were helping me, and asked if their main (new car) dealership offers dynamic/road force balancing to fix this problem. He said he wasn't sure, but that he would get that answer for me on Monday. Worst case, I'll buy it and bring it back here to have it fixed.

I believe RFB is the only proper way to balance tires and wheels after years of having shoddy work done at places that don't offer it.



We recently sold our '97 4Runner (owned since new), and bought a new TRD ORP. Ever since Toyota went to steering racks on their trucks and SUVs, they are more sensitive to any imbalance/uniformity issue. The upside is that when the tires and wheels are round, and balanced properly, they have great steering for trucks and SUVs.

I've noticed over the years that some brands seem to be able to make tires with consistently better uniformity. So those are the brands I typically look at, when I need tires.

I'd say that they need to find someone that knows how to use a Roadforce balancer to it's full capability. And tell them to turn off the 'Smart Weight' feature, as all it does is try to save wheel weights to achieve an 'acceptable' balance. You want the balance job to be as good as possible.

So after lots of research, and avoiding brands that I've had too much trouble with in the past, I chose the Yokohama Geolandar A/T G015 in LT265/70R17 E. Roadforce numbers were between 10 and 17. Not bad for a load range E 32" tire with 18/32nds tread depth. They ride smooth, are quiet, no vibration or shimmy up to 80 mph, They did great in a late spring snowstorm and rain. Pleased so far.

[Linked Image]
[Linked Image]
 
Originally Posted by Char Baby


You know which tire dealer I'm talking about. They're name is smeared on every Buffalo Bills backdrop during TV interviews.


I sure do... and the DT doesn't stand for discount tire given we have none of those around.

It's been many years since I've bought tires from them.
 
Back
Top