Rear rack without upper mounts

[ElyDave]

So, the Dahon has unthreaded holes on the rear forks, both threaded and unthreaded on the front. 

All the racks I can see have two mounting arm at the top to secure the rack to other threaded eyelets, which are simply not there in this case.

So are there any racks out there that will mount directly onto a frame with some kind of a clamp, front or rear?

[Torslanda]

Seat collar with rack mount

[ElyDave]

Thanks, seat collar is integrated with a QR rather than separate, but that does give me the idea that a large jubilee clip just beneath that, or some of my drilled steel duct mounting strap could be a suitable bodge workaround

[Chris N]

https://www.sjscycles.co.uk/luggage/carradice-bagman-2-seat-post-collar/ ? 

[ElyDave]

yes that would work 

[Bledlow]

So, the Dahon has unthreaded holes on the rear forks, both threaded and unthreaded on the front. 

All the racks I can see have two mounting arm at the top to secure the rack to other threaded eyelets, which are simply not there in this case.

So are there any racks out there that will mount directly onto a frame with some kind of a clamp, front or rear?

There's always the traditional P-clamp on each seat stay in place of frame eyelets. Tubus does a fancy version. http://www.wiggle.co.uk/tubus-clamp-set-for-seat-stay-mounting/

On most  racks I've seen (e.g. the Tortec Ultralite)  the arms are adjustable which slide back & forth in slots, & may even swivel (& have to be clamped down), so should be pretty easy to bolt on to such clamps. All that's needed for unthreaded holes are nuts (perhaps nyloc) & long enough bolts.

Also, Pletscher does racks with a single point fixing to a seatpost clamp.

[12boy]

P-clamps are available at most hardware stores and work fine for creating an attachment point. Really inexpensive, too. They bolt on to a chain stay, or if you get a large one, a down tube.