I just paid $200 to have my tires balanced

Zeke · 05-19-2003, 07:16 PM

No, I don't have stupid written across my forehead. At least I don't think. Here's the story:

Now this is on a Boxster, but I had the same thing done to my 911 15 years ago by the same guy. The process starts with trueing the tires (shaving) just enough to make them round. The guy claims the .001" out-of-round at 70 mph exerts 10 lbs. of force. Then he computer balances the tires to distribute the weights for a dynamic balance. Then he installs the wheels and rechecks trueing with a portable shaver. Lastly, he spins them up and trims them out with a strobe. The car is perfect at any speed. It won't shake a feather taped to the steering wheel.

On the 911, his process (for which he has 3 patents) resulted in Potenzas lasting over 40,000 miles and showing good tread when I sold the car. The wheels are indexed and are not to be rotated, which I never did.

Now I realize this is over the top. In his shop right now are tires from two land speed record vehicles and some race cars. For extra camber in stock classes where reslotting the bolt holes is not allowed, he builds more camber right into the tread. The last twenty bucks was for filling the tires with NO2 which I didn't think was necessary for a street car, but it's his thing. I don't fight it.

He's doing my race car tires, too.

Doug Zielke · 05-19-2003, 07:21 PM

NO2 ???

Two Oh · 05-19-2003, 07:29 PM

I'd say $200.00 well spent.

Neilk · 05-19-2003, 07:31 PM

I was hoping to see that you lived in Canada.

Why not fill the tires with Helium to reduce unsprung weight in the suspension?

Eugene at Pelican Parts · 05-19-2003, 07:39 PM

did you balance the steering wheel too?

engken · 05-19-2003, 08:00 PM

Most likely N2 (just plain old nitrogen - air minus the O2) not NO2. NO2 is nitrogen dioxide, part of the Nitrogen Oxide (NOx) family. NOx is formed by burning fuels at high temperatures. NO2 forms nitric acid in the air and also plays a part in the formation of smog, so I don't think your tires are being filled with it. Not trying to be a smart A@#, just trying to clarify things.

ZAMIRZ · ZAMIRZ's Garage

I believe I've tested this guy's work before in non-Porsche applications and must say that I was impressed. The ride quality was improved a lot at high speed, but IMHO not enough to justify blowing $200 for a street application. However, if I had a racecar, I would not hesitate to make it one of the first things I'd do.

carnut169 · carnut169's Garage

Nope. It would be the last thing you would do...
You rip tires up so quickly that there is no way a racer (at least a club racer) would spend $200 on a balance. Many of us use bubble balancers...

masraum · 05-19-2003, 09:02 PM

I don't know, if I had a little more extra cash after paying the bills and had access to a guy like that I think I would do it. I think it would actually make more difference on street tires that are around longer and log more miles. probably reduces the amount of heat when on the highway, easier on the suspension, I can see the tires lasting longer (tho' 40000 is hard to imagine, but I am open to the possibility). My 730's went about 15-20 on the rear, and the fronts have at least that much more.

They say the biggest handling improvement that you can buy for the car (excluding driving lessons) is tires, so it makes sense that they could also use the most precision when preparing. I bet at anywhere from 70-100 mph which I'm sure we all see (some of us daily) exerts a huge amount of force/stress on the tires and even the tiniest imbalance would amplify and be considerable at that speed, even if we don't feel it in the car.

Zeke · 05-19-2003, 09:23 PM

Quote:

Originally posted by engken
Most likely N2 (just plain old nitrogen - air minus the O2) not NO2. NO2 is nitrogen dioxide, part of the Nitrogen Oxide (NOx) family. NOx is formed by burning fuels at high temperatures. NO2 forms nitric acid in the air and also plays a part in the formation of smog, so I don't think your tires are being filled with it. Not trying to be a smart A@#, just trying to clarify things.

Thank you. I was wrong and need to go back and revisit my high school chemistry book. Still, that's an easy 20 skins for the guy.

He won't charge $200 for the race wheels. We realize that the tires are consumed too fast to spend 3+ hours dicking around balancing them to the gram. But let me tell you, at 300, 400 mph or bettter, the tires are the ticket. And this guy will spend an entire day on one land speed record wheel and tire.

Another therory: Don't have the scientific term for it, but we all know that the closer to the center of the spin the weight is, the faster the revolutions. Like the figure skater. With a perfect wheel, no energy is lost. The tire is always in agreement with the road surface. At least it's not going up when the road undulation is going down. So the contact patch is maximized.

I know of at least one POC Tribute to LeMans racer who has his tires done here. And I don't think he wants that information known. If he is 2-3 tenths faster becuase of something simple, he would rather keep those tenths to himself. Can't say I blame him.

I'll tell you what, that Boxster is a whole new car. Now, if i can just get some NO2................

jphillips-998 · jphillips-998's Garage

Okay, $200 seems like a lot when costco can do it for $36. However, my race car guy gets over $300 and doesn't do half of what has been offered here. I think this $200 is very well spent. Additional mileage aside, the fact that your tires and wheels are perfectly balanced is worth that much. Now you will know for sure if you warp your rotors or have other problems.

As for the nitrogen, it does not condense and "sweat" like air does. When you are generating high temperatures without adequate airflow what happens? You create steam, just like in a shower. The steam w/no where to go creates water which "unbalances your wheels. The water generated is not an insignificant amount. I have heard as much as a pound or two per wheel.

Now before all of you engineers jump on me, let me say that I really don't know what I am talking about. This information was taken from a PCA racer school and offered by an engineer who runs nitrogen in his tires.

I wish you were in Illinois, I would gladly pay $200.00 for the service that you have received.

snowman · 05-19-2003, 09:30 PM

Sucker specials

Zeke · 05-19-2003, 09:50 PM

Quote:

Originally posted by jphillips-998

As for the nitrogen, it does not condense and "sweat" like air does. When you are generating high temperatures without adequate airflow what happens? You create steam, just like in a shower. The steam w/no where to go creates water which "unbalances your wheels. The water generated is not an insignificant amount. I have heard as much as a pound or two per wheel.

One older, I assume now expired, patent that this guy's former partner (now deceased) had was a tubular ring with BB size shot in it. The ring was about the diameter of the rim and attached under the old full size wheel covers or hub caps as some called them. The effect of the BB shot was to find the imbalance at any speed over 10-15 mph and balance the tire/rim ass'y. When you stopped, all the BB's went to the bottom of the ring ready to spread out again. This only balanced the tire/rim in a single plane. These guys learned soon after about dynamic balancing (this was in the late '50s, early '60s) and abandoned the tubular ring. My father had this on one of his cars. It worked.

So, I don't know how water would be inside the tire, but if it found a pocket on the inner suface of the tire and couldn't distribute itself like the BBs, then I could see the problem.

Milu · 05-19-2003, 10:54 PM

It's my understanding that the use of an inert gas to fill the tyres is for more stable and consistent temperatures in use.

BGCarrera32 · 05-20-2003, 06:43 AM

Does he have that special machine that shakes your oil cans before changes??

Don't forget to dynamically balance your wiper blades...

Crachian · 05-20-2003, 07:07 AM

Maybe I'm a sucker too, but I spent $100 having my wheels "road force balanced" last week and the vibe at 75 mph is gone and my car feels very happy, stable, and quiet at speed now.

I followed advice from this board and found a nearby GSP9700 via:

http://128.242.141.111/pub/search/findgsp9700.cfm

KTL · 08:13 AM

I can see how precision balancing would benefit an ultra-high speed car. Makes perfect sense to me.

But on a street car I don't know. Plus, your precision balancing is subject to the quality and precision of your alignment. If you've got poor alignment on your car? It's going to negate your precision wheel balancing in no time.

Just a thought.

Another thing that Jeff said........ that water weight. I'm wondering if that's a pound force or a pound weight? I guess it would have to be a pound force. If it were a pound weight, 1-2 pounds of water would be approx. 1/8 to 1/4 gallon of water (1 gal. of water is in the neighborhood of 8.33 lbs.)!!!! That's alot of water in your tires!!!!!

I think you'd hear a lot of sloshing in there. So I think I answered my own question. Gotta be pound force, not pound weight! Duh.

That Hunter road force balancing machine is the hot setup!

Harold_89_911 · 05-20-2003, 08:32 AM

Aren't you worried about potholes or other street surface irregularities? I would be too afraid to drive a car and potentially upset the perfect balance/alignment. I agree that it must be nice while it lasts...

agabriel · 05-20-2003, 09:04 AM

I agree with Harold. It sounds like they set this up for an ideal road, like nothing I have seen in this country. I think proper inflation and alignment, perhaps if things get out of hand shaving are all thats needed. Most roads even highways aren't smooth across the pavement settles where trucks drive over it etc. My car is properly balanced and I keep the tires in good shape - I have no negative feedback with the sterring wheel either. If your going to spend the day at 200mph on a track perhaps, but otherwise you can get similar results otherways.

What kind of tires are you running?

I have Eagle F1's on mine.

Anthony

tiorio · 05-20-2003, 09:41 AM

Quote:

Originally posted by Harold_89_911
Aren't you worried about potholes or other street surface irregularities? I would be too afraid to drive a car and potentially upset the perfect balance/alignment. I agree that it must be nice while it lasts...

I don't know doodie about the physics involved in this thread but I find it fascinating. Although I understand your statment and see your point isn't this kinda like saying why pay to have your car professionally detailed if you're just going to drive it and get it all dirty? Aren't you afraid of bugs on the windshield?

No matter what you do to your car, it is finite and will eventually wear out, no?

Not trying to argue w/Harold's point but just playing devil's advocate a bit...