Static vs. Dynamic

[surflvr911sc]

I had new tires mounted on my new (to me) 7 & 8 Fuchs today and they didn’t scratch them!! Will post pics next week.

I was wondering about balancing. They balanced them statically, i.e. just in rotating and not inside/outside. Is this going to be a problem? I definitely don’t want weights on the outer rim but I had always had weight put on the inside of the rim to dynamically balance them. The guy doing the balance was concerned that it would take too much weight that way and I wasn’t sure about caliper clearance if weight was all the way to the inside lip of the wheel (stock calipers). I'm afraid of finding out the hard way by barely being able to hold onto the wheel while driving.

I don’t remember if the last tires I had balanced were balanced statically or dynamically but I will find out tonight when I take them off. The car is 100% street so far but want to be able to track it in the future. Any advice appreciated, TIA.

[KFC911]

I had a set mounted & balanced a couple of weeks ago, and the 8 inchers were done statically. (The two attempts at a dynamic balance called for a large amount of weight on each side, and even then, they didn't balance after the weights were attached.) However, the 7's were no problem dynamically (w/ a minimal amount of weight on each side). Obviously, having both balanced dynamically would be better, but I'm thinking that the "fronts" are more important. On the 8's, was it a 'lack of knowledge and/or technique' at the tire shop, or is this the 'nature of the beast' with wide 'offset' wheels?

[Zeke]

Whenever a tire takes more than 2 oz. of weight, something is amiss. It either needs to be rotated on the rim, or another tire should be selected. As far as static vs. dynamic is concerned, no one can get it perfect UNLESS, first the tire is trued, second the tire is balanced on the computer and third, the whole tire/wheel assembly is stobe balanced on the car. At that point, you never rotate or change the indexing of any wheel. My tire guy says if the alignment is spot on and the tires are balanced perfectly, the need to rotate is moot. People running different wheel sizes and/or tire sizes rejoice over this.

[sammyg2]

In most cases a single plane balance (refered to previously as static) is good enough. In some cases you will still get shake. I can see this if the rim is bent, the tire has seperated a little, or if it's flat-spotted.
The best way to do a two plane balance to remove couple unbalance (sideways wobble) is to first spin up the wheel without the tire and record the unbalance. Then, install the tire and index it in degrees for a benchmark. If it does have a significant couple unbalance, the tire can be rotated on the wheel to compensate and minimize the amount of balance weights necessary (gotta do the math first).
Another way to compensate is to add weights inside the rim (and tire) where the pressurized air goes. That way they are hidden and you can add more weight. Only downside to that is the tire has to be unmounted and remounted with every move, and the balancer has to be very careful not to dislodge the weights. Usually cheaper and better to get a new tire that is within tolerance.
BTW, if you ever get a new set of tires that are waaay out of balance, they are defective that can be exchanged as long as the wheel is not the problem.

Yesterday I had my new Yoko AVS tires mounted and balanced. I asked the technician for the finished numbers in gram/inches. I told him I needed the numbers for tech inspection or some BS like that. He looked at me funny and proceeded to re-balance the wheels, apparently to a tighter tolerance :-)

[NapTownSpeedy]

I used to work for the company that supplies all of the tires for IRL and CART (will remain nameless). When we were doing the testing for thier first modern Indy car tire several years ago, we always got better response from the drivers with Static balance. In fact even the teams that wanted dynamic, we checked static to make certain they were with in spec (<0.10 oz).
Plus when we used to do the SuperCar series, which ran on street tires (shaved RE71's) we static balanced everyones stuff. Including Hurley Haywood and Hans Stuck's 911 Turbos.
Moral, as long as you take care of your treads, and check the balance at regular intervals like a good owner, static will be just fine and you won't dirty the rim of your Fuchs.

[Superman]

Weights on the center area of the inner part of the wheel do not mess with any brake parts on my stock SC with 6 and 7s. I don't know why, but tire balancing seems to be a lost art. Yes, we have computers do to the decision making now, and perhaps that is part of the problem. Those fancy computer sustems today seem to properly balance tires about 60-70% of the time. The rest of the time, they are out of balance. Go figurre.

In the olden days there were only static balancers. In those days, freeway speeds were posted AT LEAST 70 mph and there were no radar guns. Actual speed on slow freeways was 75-80 mph. Actual speeds in faster areas were 80-90 mph and in Nevada and Montana.....cruise control was a heavy brick placed on the accelerator pedal. In those "olden" days, the only tires I ever had balance trouble with were the ones that were mounted and not balanced at all. I have never, EVER had a problem with a staticly-balanced tire. I wish those bubble balancers were in every tire shop. If they were, I would require they be used to balance my wheels.

Post Script. I once watched a guy balance two tires on the rear of my small pickup, using a pair of pliers and a floor jack, without taking them off the vehicle. They were smooth as silk when he finished. Why can't punks balance tires using expensive computerized machines?