Over the past several thousand miles my 919 has developed a noisy low speed vibration,1500-2500 with light load. More vibration in the bars, and I noticed that with cruise control on and low speed, I had a shimmy at 40mph.
Yesterday I decided to check my steering stem bearings.
1st thing, the chrome top lock nut should be 65lbs of torque. Nope was pushing 10-15 lbs. Further disassembly found that the lower lock nut was loose on top of the adjusting cone. The tabbed lock washer was in place, but, it was less then finger tight. I could grab the nut and washer while installed and wiggle the whole shebang.
I torqued the cone, 18 lbs and installed the washer and lock nut tight against the cone. Then re-assembled the top triple, and torqued the chrome nut to 65lbs and finished up. After about 60 miles some of it in the rain. I can say I found all three bugs.
No vibration in bars, noise in front end, or shimmy at low speed.
I didn't take the bearings out for greasing, because, I grease mine often thru a zerk fitting on the steer column.
If you're having any of the three problems I listed you may be as lucky as I was.
Rubber down and hormones left at home, make Joe an old rider.