Originally Posted by
Peterpan1
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I am not a big believer in the integrated rack. I don't see the point. If the idea is that one needs to have a stronger attachment point, there is no reason why that has to be done at the cost of reducing the versatility and options for a rack. ... There isn't anything wrong with properly sized bolts. But the attachment points should be larger. The current eyelets were really designed for fenders...
A welded joint can transmit torque through the joint; a screw connection cannot transmit any torque. Hence, an integrated rack can handle lateral loads such as the bags wagging left to right. The tubing can be downsized because the loop over the rear wheel does not have to be as strong.
This torque is akin to how motorists put load-adjusting bars on a trailer hitch to transmit torque to the frame of the towing vehicle. It is the same torque that S&S Couplers are designed to transmit torque through the top tube and downtube of a bicycle.