Originally Posted by
oldbobcat
But yeah, a thick washer and a longer bolt would make it a dandy mount for a rack stay.
Originally Posted by
smasha
As I noted, above, that's actually worse than nothing. With a "naked" bolt, the downward leverage is only there when the rack is weighted. With extra fittings, the downward leverage is there when the bolt is tight, and increased when the rack is weighted.
I think you’re grossly overestimating the force vectors involved here, and also underestimating the margin of difference in a flush joint -v- 1-2mm off spacers. A flush joint will support the hundreds of pounds you intend to carry, but a >2mm offset will cause the bolt to bend?
If I was installing this rack, I’d either use a couple brass crush washers to fill that gap, or an aluminum sleeve, beveled to match the profile of the fork. I could probably do it in about an hour, with the materials in my garage.
You could also upgrade the mounting bolt itself; instead of the Grade 5 SS typically used, you could get higher strength Grade 8, or source some NAS “Aerospace” grade hardware.