... ok I didn't try that, LOL. It worked fine.
I will get my bud Fern to weld the basic layout for a rucksack mount soon.
1) made for Cruzbike
2) it is inserted into the old seat tube, now the new seat back holder
3) this is a seat-post sized pipe.
4) it requires a notch to fit past the Cruzbike seat back mount
5) this is good cuz it prevents the mount from pivotting.
6) after the round notched pipe extends high enough to be clear, a
7) square tube arrangement is welded on
8) to prevent the rucksack/backpack from pivotting sideways
9) this square tube system is telescoping, with 2 sizes of square tubing,
10) to adjust in height for either a backpack or rucksack.
11) at the top there is a 'T' branch with guides to
12) hold the pack like shoulders do.
When not in use, this folds down behind the Cruzbike seat back.
I suppose the 'shoulders' can be on hinges to also fold down. A coupla pins can raise them.
I personally get nervous with a backpack laid flat on an aftermarket pannier rack.
If it catches in the tire... ouch.
Plus the rack would not block the tire.
Even with folding baskets, there are many ways for straps to sneak in.
A problem inherent with a recumbent bicycle is the inability to wear a backpack.
As an ex-student I wear one often.
I never got into panniers, and don't like them.
They are not easy to carry off a bike, unlike a backpack.
Obviously there is no need for the telescoping rucksack option.
But for somebody pondering road trips, I need more storage.
You'd want to carefully pack the heavy stuff low to not shift the centre of balance up.
The other unorthodox solution is... use a hard-external-tube rucksack as the seat back.
So the bike literally has no seat back when you leave it.
This would require some tube modification at the bottom to function as a seat back.
I came up with this one when I read of folks cannibalizing suck rucksacks for seat backs.
Kill 2 birds with one stone, I say!
Extending this concept of dual function has benefits.
A bike light ... that is a fully functional flashlight.
The only other project I can afford this winter will be the propanetank mod'd air-horn.
I live near the universities, and students walking with their I-pods or phone-texts must be the most oblivious pedestrians on Earth!
The lil' ring sound of my bike bell just doesn't cut it.
As soon as I can replicate a train horn, I will!
The look on their face will be worth it.
Ditto cars that cut me off...
I'll post pics when I start building.