The shear bolts are there for a reason. If it doesn't shear things can break that are very costly to replace. The bolts do beak every now and again just from starting and stopping the fly wheel. Or if you pick up an chunk of wood, a large stone, try to start the baler with a large slug of hay in it, if the timing gets too far off, etc.
If you search this forum for 336, and 346 you should come up with a lot of information. These balers have been discussed many times over the years here.
I know what shear bolts and slip clutches are, just didn't realize I might be needing that many. Maybe it is how people start the balers also. I have very limited knowledge on square balers - doing my homework, etc.
D.