No, I have not calculated the tension in the bolt. I'll have to do a little research to find out the diameter and grade of this fastener. If memory serves, the suspect fastener is an M8. My Unbrako engineering guide recommends a seating torque of 35 Nm. Bear in mind that this is for a high toughness, high strength heat treated steel with a minimum yield stress of 940 MPa. This is probably a considerable upgrade to the bolts used on our Triumphs. So, a torque of 27 Nm looks reasonable to me. 45 Nm appears to be way too high.Yeah, we've seen that. Does your manual show this?
I believe that is referring to these:
The text for the section on removing the headers on the Bonnie confirms that those bolts marked above should be at 27Nm.
But can't find anywhere the torque listed for the clevis bolts. It's listed as 45Nm for the America, but nothing for the Bonnie in my manual. Passenger ones are listed as 27 Nm in the later chapters. I assume the bolts are 27 Nm as well. I had just assumed that when you did your closed form equations to determine that this joint was properly engineered that this torque value would have come up, and hoped you remembered.
My gut instinct, it does seem like 45 Nm is too high for that bolt, but that's just a gut instinct.
With a torque of 35 Nm (310 lbf in) an M8 bolt (diameter 8mm or 0.315 in) and "K" value of 0.20, the preload on the fastener holding the two brackets together is over 4,900 lbf. I think that you can see that if the torque is not to recommended value, the preload will be considerably less.
My manual shows the torque for the Footrest to outrigger locknuts as 27 Nm for the Bonneville, Bonneville SE, and Bonneville T100. It shows 40 Nm or 45 Nm for the Outrigger to frame bolts depending on whether they are silver bolts or black bolts