Keep losing wheel balance

[jwakil]

I have a set of Fikse Fuch replicas on my car. The front wheels have become imbalanced multiple times. I had them balanced by NTB and were good for a while then I started getting excessive steering wheel vibration at certain speeds. Had them rebalanced and they were good for about a day and now the steering vibration is back. The shop told me that these wheels have to be statically balanced and were more prone to losing balance. To me it seems the only way a wheel would come misbalanced would be if the weights fell off or something. These weights seem to be glued on the inside of the rims. Has anyone else experienced this issue? Is there a different way to balance these to keep them in balance?

[ChrisBennet]

That's pretty wild. I'm looking forward hearing what people say/what you discover.

I'll add a couple of data points from my experience. These events happened at the track so they probably aren't applicable but "in the interest of completeness" as they say..

- Got some new track rubber mounted the morning of a track event. Later under braking, the tire actually slipped position on the rim. I guess the combination of tire lube and threshold braking was enough to move it. After that, I would make a line on the tire with chalk next to the valve stem to detect this happening.

- I've experience the stick-on weights adhesive melt, the weights move and then remain stuck. Some of that silver metal duct tape over them keeps that from happening.

[Sooner or later]

Mark the wheel and tire and see if you are having the tire slip on the wheel. Happens more often than not.

What kinds of bs are they feeding you about the wheel/tire can only be static balanced. You want them dynamically balanced . Proper dynamic balance will require weights on the outside and inside of the wheel. Static balance will not correct for all balance problems.

[Sooner or later]

Static balance is looking for the heavy area of the tire. Basically you place the wheel tire on a pivot and see which direction the tire leans. You then place a weight opposite the heavy side to balance it statically.

The problem with static is that you may have the serial side (blackwall side where all the dot data is located) be an ounce light while the non serial side (whitewall) is a ounce light 180 degrees (circumference) from the serial side light spot. The two sides will weigh the same so no static balance weight will be needed. Put that perfect static balance tire on a dynamic (rotate at speed) machine and the tire will need an ounce on each side to keep the tire from vibrating at speed.

Never accept a static balance as being acceptable.

[T77911S]

did you have other wheels on the car and if so did you have vibration problems.
how is the front end on your car. is the bushing in the steering column bad/been replaced.
how are the tie rod ends.
ball joints
excessive play in wheel bearings
not sure if bad shocks would effect this.

these things may not cause the problem but they can let the problem be worse than it is.

have the wheels checked for trueness. are they bent.
can you swap the fronts and rears
alignment
cheap tires/bad tires. tires can flat spot just sitting.

I have not seen a shop that can do this in years but if you can find a shop that can balance the wheels ON the car, that will fix the problem.
you need to find and old shop with an old guy there because the new kids wont know what this is.

[Sooner or later]

Originally Posted by T77911S

did you have other wheels on the car and if so did you have vibration problems.
how is the front end on your car. is the bushing in the steering column bad/been replaced.
how are the tie rod ends.
ball joints
excessive play in wheel bearings
not sure if bad shocks would effect this.

these things may not cause the problem but they can let the problem be worse than it is.

have the wheels checked for trueness. are they bent.
can you swap the fronts and rears
alignment
cheap tires/bad tires. tires can flat spot just sitting.

I have not seen a shop that can do this in years but if you can find a shop that can balance the wheels ON the car, that will fix the problem.
you need to find and old shop with an old guy there because the new kids wont know what this is.

If you balance on the car you must put the wheel/tire back on with the hub in the exact same position. Lugs must stay matched to home wheel hole.

[metalracer]

I chased a problem like this many years ago on a Miata. Moved it to every corner of the car, balanced it every way from Sunday including kinetic-in-place, etc. Finally, pulled the tire off the wheel and discovered a couple broken reinforcing cords. New tire = problem solved.

[gtc]

Have they checked inside the tire?
I've seen some tires lose pieces of rubber inside, which leads to strange balance issues.

[brianlay]

dismount and check inside the tire. I once had water in there and had the same symptoms you describe.
Water may get in there from a compressor without a water separator.

[flat6pilot]

Describe the vibration: (I also have a set of Fikse Fuchs)

Does the steering wheel 'oscillate' rapidly back and forth (I'm talking a 1/2" or so of travel) when you lightly hold the wheel?

If you grip the wheel, does the vibration go away (mostly) or can you feel it 'fight' you under your grip?

[jwakil]

Some more info:

The tires are new.

Not sure how to check for stuff inside without dismounting. The fact that the balance was good for a while after each balance leads me to believe it is not something floating inside or broken tire.

The steering wheel oscillates clockwise/counter clockwise and goes away if I hold the steering wheel firmly.

[GH85Carrera]

My 911 is super sensitive to wheel balance. I fought it for years with different tire shops. I finally found a place that does a "road-force" balance. First the spin up the wheel with no tire. Then they mount and balance the tire but the balance machine applies the force of the tire on the ground and they spin it at a higher rate of speed than many companies. In the end it works great.

[Sooner or later]

Originally Posted by GH85Carrera

My 911 is super sensitive to wheel balance. I fought it for years with different tire shops. I finally found a place that does a "road-force" balance. First the spin up the wheel with no tire. Then they mount and balance the tire but the balance machine applies the force of the tire on the ground and they spin it at a higher rate of speed than many companies. In the end it works great.

He needs to find a shop with one of these.



Wheel & Tire Balancer | Road Force Touch® Wheel Balancing Machine | Hunter Engineering

[Sooner or later]

He needs to check for tire/rim slip first. Mark the wheel/tire with a crayon an then several heavy braking stops.

[Sooner or later]

If there is no slip move one tire side from front to back. No change then move the other side.

He can narrow the possible causes down to a manageable level..

[Sooner or later]

Houston area. Hunter Road. Force machine.



Texas Tire Shop Locations | Beasley Tire Service Inc.

[Sooner or later]

A question for the OP.

Are you able to "drive through" the vibration. Is it worse at say 15, 30, and 60 but smooths out in between? If so then most likely tire wheel

If you have the shake at all speeds it looks more like worn steering/suspension parts.

[jlex]

Sometimes the tires are out of round. They seem okay for the most part until they synchronize with each other. You can balance them all you want, but it won't help. The only cure is to find a shop with a tire truing machine that will cut the treads until the tire's perfectly round.
To see if they're out of round, jack the car up, then put a stationary object near the middle of the tread. Rotate the tire to see if it shows near and far gaps from the object when rotated.
They're making tires better these days, so many shops won't true tires anymore; they look at them as defective, and merely replace the tire. Back in the day when I worked in a shop over the summers, I saw many tires that needed to be trued. It's possible that you ended up with bad, out of round tires...

[Sooner or later]

Originally Posted by jlex

Sometimes the tires are out of round. They seem okay for the most part until they synchronize with each other. You can balance them all you want, but it won't help. The only cure is to find a shop with a tire truing machine that will cut the treads until the tire's perfectly round.
To see if they're out of round, jack the car up, then put a stationary object near the middle of the tread. Rotate the tire to see if it shows near and far gaps from the object when rotated.
They're making tires better these days, so many shops won't true tires anymore; they look at them as defective, and merely replace the tire. Back in the day when I worked in a shop over the summers, I saw many tires that needed to be trued. It's possible that you ended up with bad, out of round tires...

They are new tires. If they are out of round (radial run out) they should be replaced. RRO tolerance is around .030":

[jwakil]

Originally Posted by Sooner or later

A question for the OP.

Are you able to "drive through" the vibration. Is it worse at say 15, 30, and 60 but smooths out in between? If so then most likely tire wheel

If you have the shake at all speeds it looks more like worn steering/suspension parts.

Vibration seems to be bad between ~40 and 65mph, and ok below and above.

I'll have NTB do a dynamic balance first with a different weight attachment method, as I paid for the lifetime balance last time. Will mark tires too. If still have issues then will try the force balancing.