If this reasoning is true then it means that different torque wrenches would obviously yield different torque measurements, but this defies common sense. Is it not true that whatever wrench one uses should have submitted itself to some common standard? Otherwise every manufacturer will have his instrument not compatible with the others in the industry? I am so confused.
Those of you in the know, why don't you also help by showing what needs to be torqued using a diagram that shows the different pieces in the steering mechanism.
Torque is literally a force applied tangentially a distance away from the center of rotation.
Imagine a rusted lug nut on a car wheel. You put a lug wrench on it and push down on the end of the lug wrench. If the lug wrench is 1' long, and you push on it with 100lb of force, you're applying 100 lb x 1 ft, or 100 ft-lb of torque to the fastener.
It's still stuck. In desperation, you put a pipe on the end of lug wrench, which makes the lug wrench effectively 2' long - doubled in length. If you now apply the same 100 lb force to end of the now 2' long wrench, you get 100 lb x 2 ft or 200 ft-lb of torque on the fastener. The added wrench length increases the mechanical advantage (leverage) of the twisting force you're applying to the lug nut.
The design and calibration of torque wrenches accounts for their length. If one torque wrench is twice the length of another, it will only require half the force to actuate.
Our bike's service manual specifies a torque to apply to an
offset spanner - a special short wrench - NOT directly to the fastener itself.
To abuse the lug wrench analogy more, cut your lug wrench into two pcs, then weld the two pcs back together at a 90 degree angle to form an L shape... with a weld that will fail at 100 ft-lb.
When you push on the end of the lug wrench, what happens? Well, the weld breaks when it reaches 100 ft-lb... but just before that happens, how much torque is the lug nut getting?
Answer: I don't know - but there's an equation to figure it out in the thread linked a few posts up. It's not necessarily 100 ft-lb, tho, because your pushing force is no longer tangent to the fastener, it's tangent to end of the offset spanner.