A rule of thumb for any journal bearing is that a good, used journal bearing is better than a new journal bearing.  For that reason, changing rotor bearings is not an option for most people.  Only those with bad or damaged rotor bearings or those going to a big power motor rebuild need to change rotor bearings.  If you do want to upgrade rotor bearings on an FC3S 13BT motor, go with the stock FD3S rotor bearings, as the FD3S rotor bearings have a deeper oil groove for better oil lubrication.  If you do go with new rotor bearings, the break-in period is extended up to 4,000 miles, or double what the normal 2,000 mile break-in period.

Questions?  Comments?  Send mail to:  reted@fc3spro.com