Road force balancing tires?

[Da Dark Jedi]

This may not be the correct forum but I've read a number of posts regarding shimmy as well as the term "road forced balancing" of tire. Not ever hearing this term I googled it and found this explanation on the net.

Road Force Balancing Tires

You have to remove the wheel and tire from the vehicle to have it road force balanced. What the machine does is spin the wheel/tire slowly while pressing a roller against the tread with about 1400 pounds of force. It measures the "loaded runout" of the wheel/tire combination. Then it measures, using other rollers, the runout of the wheel where the bead seats. Then it instructs the user to mark the tire and the wheel, remove them from the machine, break the beads loose, rotate the tires on the wheel to match the marks, then re-inflate and re-mount the wheel/tire on the machine. Then it spins it again to measure the results, then spins it up so balance weights can be applied in the usual manner.

OK, now what's it REALLY doing?

It models the wheel bead mounting surface as a circle that is not necessarily concentric with the rotational axis of the wheel. For the technically literate, that's the first order radial harmonic. It models the tire as a circle that's not necessarily concentric with its beads. It then computes how to mount the tire on the wheel so that the "high spot" of the tire is at the "low spot" of the wheel. Again for the technically literate, it puts the first order harmonic of the tire out of phase with the first order harmonic of the wheel such that they cancel as much as possible.

What that does is minimize the net loaded radial runout of the wheel/tire combination. In layman's terms, it makes the tread surface, under load, as round as possible, relative to the axis of rotation of the wheel.

Does it work? Absolutely. Very expensive machines are used to do the same thing with the tires and wheels that are mounted on new vehicles at the factory. The Hunter GSP9700 does it just as well and it does it in a tire shop. Ask Michelin -- their engineers bought the first six of them Hunter produced.

You can road force balance wheels at any time. Tires sometimes change their loaded runout with wear, and road force balancing can improve their performance.




Now here's my question...Does MM owner have this done regularly? If so how often? If not why?

[FordNut]

Lots of us have it done. Usually only at the time of new tire purchase.

[Bluerauder]

Lots of us have it done. Usually only at the time of new tire purchase.
+1 ^^^^^ 789

[fastblackmerc]

+1 ^^^^^ 789

+2 ^^^^^ 789...

My tire guy only does road force balancing.

[chader]

NIGHT AND DAY..works well on the big wheels

[ctrlraven]

I've never heard of it. I'll have to check on that the new time I get new tires mounted.

[sweetair]

Lots of us have it done. Usually only at the time of new tire purchase.right there with him. Only done once at new tire purchase.

[QWK SVT]

NIGHT AND DAY..works well on the big wheels

In what way would you consider it "night and day"? By that, I mean what specifically do you feel has improved, as a result? (just asking cause I've never had it done)

[Adam12]

id do it every time you rotate the tires side to side so every 10k miles or so

[lifespeed]

While it sounds like a good idea, is it always necessary? If one's tires and wheels are actually concentric (as they are supposed to be, although we know things are not always perfect) and no vibration is occuring is there any advantage to doing this?

[Adam12]

it will prolong the life of the tires by alot....well at least the fronts.....lol

[Da Dark Jedi]

Well... After 3 phone calls to places here (recommened by Tire Rack) NONE of them offers this service. So far "Spin Balancing" is whats being offered. One place went as far to tell me "Normally the people who has that machine DON'T know what they're doing", but than again he has the highest price @ $138 bucks, to spin balance all 4 wheels. So this RFB is better than regular Spin, or it's in the marketing.

[lifespeed]

And spin balancing was an upgrade from the old bubble-balancing.

[chader]

In what way would you consider it "night and day"? By that, I mean what specifically do you feel has improved, as a result? (just asking cause I've never had it done)
I find the biggest difference at high speeds.What I do find is I never thought I had a vibration till I had road force balanced the my tires.The larger wheels of today18"-24" are really hard to balance properly but road forcing makes it much easier.It also helps with the feel of flat spotted tires from sitting.

[Bluerauder]

And spin balancing was an upgrade from the old bubble-balancing.
1. Bubble Balance - tire horizontal, trick was to get the bubble in the center of the crosshairs by placing weights around the rim. Usual standard was "Close Enough". Was about $1-2 per wheel.

2. Spin Balance - tire vertical and spun with a motor. Better simulation of the tire's actual rotation and effects at speed. "Much Closer". About $5-10 per wheel.

3. Road Force Balance -- very similar to Spin Balance but with a load on the tire tread itself. Much closer to actual road forces and up to high speeds. Hence the name. "Best for Now until something better comes along". Around $15-20 per wheel.

IMHO a Spin Balance is fine for the majority of people who don't push the car too much and rarely top 65 MPH.

Road Force Balance is for the folks who "Want it Right", can "feel" the slightest quirks and vibrations, and occasionally to frequently like to feel the limits of performance. :D

If you get a little squeamish above 45 MPH, then a Bubble Balance will do just fine for you. :P

[CRUZTAKER]

I only roadforce on our performance vehicles.

The machine has caught 3 bad tires (internal issues) over the years that would have been over looked by the cheap balancers and merely had the installer add 5 ounzes of weight to correct the balance. :rolleyes:

If you are adding more than 2oz of weight to a wheel to balance it, something is a piece of shat.
Either the wheel or the tire.

Having come from a family of tire engineers from Akron, Ohio the rubber capital, back in the day :(..... I heard plenty of stories from grandpa and dad of tires with f-ed up steel belts being passed through qc and out to the public. No one knew otherwise because most folks don't drive over 55.
T 130 you WILL find out if there is a mis-balanced wheel. ;)

[sicilianmarquis]

+1 on cruztakers, if ur adding anything more then like 2 oz either u got a f*d up rim or the machine is ****ty




i do about 2-3 road forces a day, pain in the ass on out part.............LOL

[Da Dark Jedi]

If you are adding more than 2oz of weight to a wheel to balance it, something is a piece of shat.
Either the wheel or the tire.)


I'll remember this point. So whats the general cost?

[CRUZTAKER]

Prices vary...

My guy only charges $8 a wheel. But that includes mount and stem.