My wife rides an 09 FXDB. This year, she has noticed that the front end has what she calls a "death shake" while cornering at speeds over 70 MPH. The bike handles great under all other riding conditions. Straight lining at 70+ creates no concerns. The bike has 20K, services are done at 2,500-3,000 miles. The stearing neck bearing is at factory torque specs, (old dirt bike racing habit), tires never get to the wear bars, pressure is 38 front, 40 rear. Prior to chasing a phantom and spending $$, I am looking for input on fork oils, fork springs and or fork braces that will eliminate the shake.