Road Force Measurement The GSP9700 Vibration Control System includes Hunter's exclusive Road Force Measurement System. This system utilizes a “road roller” which measures the uniformity of the wheel and tire, simulating a road force test and verifying if the assembly is “round when rolling” under load. Now nearly all wheel/tire- related vibration problems can be diagnosed and/or eliminated in seconds.
Vibration results when tire stiffness is not uniform. The GSP9700 Vibration Control System utilizes Hunter's exclusive Road Force Measurement® Syestm that applies up to 1400 pounds (635 kg) related vibration against the tire assembly to detect non-balance, radial force-. Lack of tire uniformity is a common and often hidden cause of wheel vibration. As a tire rolls, it flexes as if it were made of springs. Vibration results when tire stiffness is not uniform.
What you need to know about Wheel Balance & Wheel Vibration Control At 60 miles per hour, an average size tire rotates 850 time 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 such as: Excessive Tire Wear Damage to Suspension and Steering Components Unsafe Steering and Handling
Wheels Out of Balance Static wheel balancing uses a single weight plane and only addresses "up-and-down" imbalance. This is simply not adequate for today's vibration sensitive vehicles. Static wheel balance measures only "up and down." Dynamic wheel balance also measures from "side to side." Dynamic wheel balancing uses two weight planes. This eliminates "up-and-down" and "side-to-side" imbalance. Dynamic, two plane wheel balance should always be requested, even on custom wheels when hidden weights are required.
Wheel Force Variation An out of round tire (runout) causes wheel vibration. A stiff spot hitting the pavement causes vibration. Uneven tread or sidewall stiffness can be found in new or worn tires. Tires by design are never uniformly flexible throughout nor are they perfectly round. And no two tires are exactly alike in these characteristics. Wheel Force Variation is most frequently due to wheel runout or uneven tread or sidewall stiffness in the tire. Runout is when a tire or rim is out of round when rolling; frequent causes are a bent rim or uneven tire wear. A perfectly balanced tire can still vibrate due to Force Variation.
How Wheel Force Variation is Corrected OEM Match Mounting matches a high point or stiff spot on a tire... with the low spot on the rim, for maximum roundness. 1. Match mounting a tire and rim by matching the high point or stiff spot in the tire with the lowest spot in the rim, can make the wheel "round when rolling." 2. In some cases a wheel is so out of round it should be replaced. 3. In some cases a tire with excessive Force Variation is defective.
Improper tire pressure and/or misalignment causes irregular tire wear which creates and amplifies imbalance, resulting in wheel vibration. Alignment can be adjusted and wheels serviced to reduce or stop the vibration. Steering and suspension components need periodic inspection. They can eventually wear out resulting in wheel vibration. Excessive wheel vibration from other causes can also shorten steering and suspension component life. Wheel to axle mounting error Brake component wear or failure Drive train or engine component wear or failure Vehicle component characteristics Tire Pressure and Wheel Alignment Steering and Suspension Components Other Hidden Causes of Wheel Vibration
GSP9700's Inflation Station** provides proper inflation pressure for accurate testing.
Step 2: Measure Rim Runout The GSP9700 Vibration Control System measures lateral and radial rim runout without removing the tire from the rim and quickly indicates if runout is tire related. Runout can also be measured at the actual bead seat on a bare rim. The GSP9700 Vibration Control System then calculates the contributions of the tire and the rim to the vibration problem and presents the technician with easy-to-follow repair instructions.
Rim Runout Measurements Rim runout can be measured without removing the tire… …or, directly at the bead seat on a bare rim.
Step 3: ForceMatching® and Balance Hunter's patented ForceMatching® feature cancels the high point of tire radial force variation with the low spot on the rim. This helps eliminate vibration by minimizing the effects of radial force variation and rim runout. Once the repair is completed, the technician can continue with a precision wheel balance by choosing one of four balancing methods.
Matching the stiff or high spot on the tire with the low spot on the rim cancels vibration caused by radial force variation and provides the smoothest ride.
Benefits of the GSP9700's Diagnostic Repair Capability Solves Vibration Problems Balancers Won't Fix Dramatically Improves Ride Quality & Customer Satisfaction Faster Troubleshootin g & Repair Increases Wheel Service Income Detects non- balance, radial force-related problems related to: Tire uniformity. Tire and rim runout. Wheel-to- balancer mounting error. Improper bead seating of tire to rim. Duplicates vibration measurement and tire/wheel matching methods previously used only by vehicle manufacturers to provide that “new car ride.” Quickly calculates the contributions of the rim and tire to radial vibration problems and presents the technician with easy, step-by-step repair instructions. Establishes your shop as the vibration control experts. Reduces comebacks and enables you to service vehicles that other shops turn away.
Features That Make Expert Balancing Easier and Faster… Motor assist feature eliminates hand cranking of the wing nut to “take up” the unused spindle threads with a double tap of the food pedal. Inner and Outer Dataset® Arms speed entry of exact chosen weight location and double as measuring tools for lateral and radial runout. Speeds placement of clip-on or adhesive weights. Tapping the foot brake activates entry and storage of wheel data. Foot pedal also locks spindle for easier tightening and loosening of wing nut.
Features That Make Expert Balancing Easier and Faster Insures that the wheel is mounted on the balancer properly centered. Eliminates guesswork when choosing mounting accessories or questioning set-up error on problematic wheels. Guarantees the most accurate balance. Split Spoke® Mode automatically locates the best “out of sight” position for adhesive weight placement on custom wheels. Split Weight® Mode offers multiple weight choices, reduces large weight inventories and avoids trim ring obstructions. Servo Stop automatically positions wheel to each desired weight location (TDC or BDC) with the touch of a button or by simply pushing the wheel. Quickly Locate Weights Infinite Weight Positioning Prove Wheel Centering
26-inch tire and wheel assembly shown above
Specifications Roller Force: up to 1,400 lbs. (635 kg) Capacity:Rim Width: 1.5 in. (50 mm) to 20 in. (520mm) Rim Diameter: 10 in. (272 mm) to 24.5 in. (640 mm) ALU: 7.5 in. (190 mm) to 41 in. (999 mm) Maximum Tire Diameter: 40 in. (1016 mm) Maximum Tire Width: 20 in. (520 mm) Maximum Tire Weight: 175 lbs. (80 kg) Radial & Lateral Runout Accuracy:.002 in. (0.05 mm) Radial Force Measurement Accuracy: 2 lbs., 10N (1.0 kg) Imbalance Resolution: +/ oz. or 0.5 gm Placement Accuracy: 512 positions, +/-.35° Balancing Speed: variable rpm, direction and torque
Comprehensive Wheel Service Thanks to Hunter Engineering Company