http://www.moderntiredealer.com/article/729143/the-present-and-future-of-mounting-and-balancing
Quote:
Augmenting off-car balancing with on-car correction will help eliminate NVH issues
Off-car wheel balancers do an excellent job of measuring dynamic unbalance — static and couple, says Dave Scribner, product development manager, CEMB USA/BL Systems Inc.
“Many also now measure tire/wheel assembly eccentricity, or what we will simply define as RFV (Radial Force Vectoring) to help eliminate vibration.
“We must ensure the tire and wheel assembly is balanced and round when rolling; and ultimately this is when it’s on the vehicle’s hub because this is where it rolls against the pavement.”
On-car balancing solves many issues that off-car balancing cannot address, he says. “Because of gravity, the assembly centerline changes from the balancer to the vehicle hub on virtually all wheels with hub bores and lug nuts and studs securing the wheel to the vehicle. “The small clearances can make a big difference in radial force variation ride quality.”
Scribner says use a wheel balancer that measures RFV if you want to solve vibration on sensitive vehicles. “Vehicle and tire manufacturers have known for decades that virtually every vehicle can benefit from using hub-bore indexing to assist in canceling the remaining eccentricity and/or static imbalance in the assembly during vehicle mounting.
“Index the high point of RFV at the balancer and place it on the vehicle at TDC (Top Dead Center) before torqueing the lug nuts. Do it on everything. It will save time, reduce the need to match mount and always provide better quality ride.”
Quote:
Augmenting off-car balancing with on-car correction will help eliminate NVH issues
Off-car wheel balancers do an excellent job of measuring dynamic unbalance — static and couple, says Dave Scribner, product development manager, CEMB USA/BL Systems Inc.
“Many also now measure tire/wheel assembly eccentricity, or what we will simply define as RFV (Radial Force Vectoring) to help eliminate vibration.
“We must ensure the tire and wheel assembly is balanced and round when rolling; and ultimately this is when it’s on the vehicle’s hub because this is where it rolls against the pavement.”
On-car balancing solves many issues that off-car balancing cannot address, he says. “Because of gravity, the assembly centerline changes from the balancer to the vehicle hub on virtually all wheels with hub bores and lug nuts and studs securing the wheel to the vehicle. “The small clearances can make a big difference in radial force variation ride quality.”
Scribner says use a wheel balancer that measures RFV if you want to solve vibration on sensitive vehicles. “Vehicle and tire manufacturers have known for decades that virtually every vehicle can benefit from using hub-bore indexing to assist in canceling the remaining eccentricity and/or static imbalance in the assembly during vehicle mounting.
“Index the high point of RFV at the balancer and place it on the vehicle at TDC (Top Dead Center) before torqueing the lug nuts. Do it on everything. It will save time, reduce the need to match mount and always provide better quality ride.”