At normal highway speeds, an average size tire rotates 850 times per minute. At this speed, slight variations in balance, sidewall stiffness or roundness can cause the wheel to literally slam into the pavement 14 times a second. The ultra-sensitive road feel of today's vehicles gives drivers a hands-on detection of vibration, a warning of potential problems. Unchecked, excessive wheel vibration can result in expensive damages and unsafe driving conditions. There are three main types of wheel balancing used to resolve these issues: static, dynamic and the new Road Force technology.
Static wheel balancing uses a single weight plane and only addresses "up-and-down" imbalance. This is simply not adequate for today's wheel vibration sensitive vehicles.
Dynamic wheel balancing uses two weight planes. This eliminates "up-and-down" and "side-to-side" imbalance. Dynamic is the entry-level standard in wheel balancing.
Road Force wheel balancing is more accurate and reliable compared to older static and dynamic methods. This machine applies 1,200 pounds of pressure to the tire. This simulates the vehicle rolling down the road. The computer and sensors in the machine detect variation in the tread.
These variations can be corrected by aligning the high point or stiff spot on the tire with the lowest spot on the rim. This will make the wheel "round when rolling." This procedure is called Force Matching® and it solves most vibration problems
With every road force balance, we will provide you with a before-and-after printout of the results. This printout states how much weight was required by each wheel (indicated in oz). This printout will also indicate how much road force is present in each wheel (indicated in lbs).
The example printout above shows that the right front wheel (#2) had a road force of 29 lbs before performing force matching. The customer was complaining about a vibration in the vehicle that would just not go away, no matter how many times he balanced the wheels. For this vehicle (2012 Volkswagen Jetta), the limits for the road force is between 0 - 20 lbs. This excessive road force of 29 lbs was being transmitted into the steering. After performing the force matching on the right front wheel, the road force was significantly reduced to 7 lbs. We checked back in with the customer a few weeks later and he confirmed that the vibration was no longer present.
This feature is usually performed when mounting a new tire to the rim. It involve having a roller press against the bead of the tire (while inflated) to ensure that the tire properly seated on the rim. From experience, this little extra step can reduce road force readings by up to 25%. We always perform this procedure when tires are purchased and installed at our shop!
One of the most difficult handling issues to fix is a pull problem. Tire forces are the most elusive, and until recently, unmeasurable conditions leading to pull problems. Tire-related pulls are caused by lateral forces in the tire. Lateral force is the amount of left or right pull force created as the tire rolls along the road. This condition may cause a vehicle to steer away from straight ahead. These forces are primarily created by conicity and cannot be detected during standard balancing and alignment service.
The StraightTrak® feature in our Hunter Road Force machine measures lateral force then applies this lateral force information to a set of tires, providing the operator with multiple placement choices about the vehicle. Tires are tagged and positioned on the vehicle to provide the least amount of vehicle pull and obtain the best straight ahead steering ability. Pull or drift caused by the lateral forces can be systematically minimized, offset or eliminated.
Provides the smoothest ride possible using Force Matching®, Bead Massage, and StraightTrak® technology. Additional fees may apply.