Tire Balancing Act
by Pat Goss
We get a lot of questions involving vibrations in cars, and usually those vibrations have something to do with tires and tire balance. But balance isn't always the answer. Now consider this airplane, or any airplane, the propeller on it has to be perfectly balanced in order to keep from vibrating the plane apart. Yet we couldn't take that propeller and put it on a car or anything else and drive it on a hard surface, because clunk, clunk, clunk. Doesn't work. So, how does that relate to the car? Well, here we have a tire on a typical machine to balance a tire. It's balanced out here in the air. We spin it in the air. Ok, so we can balance the tire completely, but that doesn't mean that it's going to roll smoothly down the road. And the reason for that is what is called road force variation.
Now you have to think of road force variation as being oh similar to a hard spot someplace here in the tire that every time it hits it creates a vibration that's transmitted into the car. Back in the day that didn't matter because tires used to be like this, really tall sidewalls, and there was a lot of area to absorb those imperfections. Today the smaller sidewalls, the low profile tires, they're very unforgiving with this. And that means that all of these imperfections in the tire are transmitted into the vibrations and into the car. Alright, so what'd do?
The Hunter GSP ninety-seven hundred road force balancer is pretty unique in that it has this big roller here. The roller comes up against the tire as the tire is spinning, it senses any imperfections in the tire, converts that into a digital reading, and tells you what the road force variation is. And there are set standards. So, if a tire has excessive road force you can balance it, from now till next year, and it's not going to roll smoothly on the road because of excessive road force. So, what do you do?
If you're having a balancing problem, new car, new tires, old car, or old tires, whatever, you want to look for a machine like this, a road force variation machine, and dial in the road force variation to get a smooth ride. I'm sure you'll be impressed.