Good afternoon everyone.
I had to replace my head bearings as mine became feeling notchy. As it turned out the bearings were overloaded by the whoever did the service last time) and that killed them prematurely (only 22k km on the bike)
I did check the procedure that is provided in the manual and it seem to me its not possible to set the load accurately using the approach specified in the manual. The problem lies I think in the design. When the steam nut is set to the optimal setting the nuts threads will be pushed against the top surface of the stem threads (head tube and the triple tree stem being vertical) by the resistive force of the bearing balls . When the top of the triple tree is installed and the top bolt is tightened to the specified torque it will push the lock nut against the bottom surface of the stem threads and thus preloading the bearings which is not good and it decreases their life. That seems to have killed my bearings The threads being fairly coarse will have some play due to tolerance. With this design the variance in the mating threads will determine the amount of preload when the. bolt is tightened.
On all my two wheeler vehicles (bicycles mostly) I try to set the loading force to be just enough to take out the slack without loading the bearings). Bicycle systems allow this pretty accurately as the loading force on the bearings and clamping force of handlebars holder are perpendicular to each other and, thus do not interfere with each other. That approach keeps my head bearings running for long times.
Now my question is whether the community found a quicker approach other than, tighten the nut to find the resistance , loosen it 1/X turn put the top on, tighten the bolt check if the slack or preload exist, , then wash rinse repeat...until no slack nor preload detected in the final assembly
Thanks again