I am going to be replacing the tires on my car to cooper’s cs4 touring tires. General on line research has mentioned that these tires should be placed with a hunter road force balancer. I spoke with a shop that sells these tires and the salesman expressed that this was a fancy machine that did just what the eye does without the extra $70 charge/tire. Who’s right?
In most cases, road force balancing is not necessary. Road force balancing compensates for varying stiffness in the tire sidewalls and slight wheel out of round. Cooper CS4’s are a premium tire and shouldn’t suffer from an inconsistent sidewall, they are also not a low profile tire which are more susceptible to this problem. Don’t waste your money.
The Hunter GSP9700 is a great machine for diagnosing wheel end related vibrations. In particular, it can match the low point of the wheel with the high point of the tire, which results in a “rounder” assembly. (It isn’t exactly “roundness” that the machine is measuring, but it is close.)
The salesman at the shop is all wet about the “eyeball”. No one can do what this machine does without a machine of this type - and certainly not by eye. And if someone is charging $70 per tire, that’s outrageous. Most shops that have this machine charge no more than regular balancing charges.