Originally Posted by
unterhausen
I used a rack with p-clamps at the top for many decades. Given that many racks have sheet metal mounts at the top, it seems like that is clearly adequate. I have always wondered about p-clamps at the dropout though.
I would be wary of using the P clamp to hold a rack stay on the dropout area of the frame if the rack stay rested on the frame itself. I would worry that downward impact from the rack onto the frame tubing might damage the frame.
But I would use a P clamp to hold the rack stay beside the frame, so that the impact is borne by the clamp and not the frame tubing itself.
This is how the traditional M5 bolt holds most racks systems to the frame at the dropout area and the front fork.
Here is a simple drawing to illustrate - I am not an draftsman
