Or. . . . perhaps all that's needed is an announcement post in the BikeRacks headed "Thinking of Posting in a Thread Here? Read Me First!" with a clarification (and emphasis) of the rules.
Isn't this essentially what the Bike Racks sticky is (or is supposed to be)? I think the above would be a better title than 'How to Use the Bike Racks'. I think the 'Read Me First' sticky in ToE is very attention grabbing. And I'm all for revising the sticky to make things clearer. Nice big, bold type, perhaps, for the crucial points.
I would oppose making the Bike Racks read only, for the reasons stated.
I like the idea of a reminder in the thread title.