Originally Posted by
Duragrouch
And... call me Dura.
EDIT: In terms of stability, I agree, you can carry more on a frame mount than steered on a front rack. However, in terms of structural design to support loads, usually front racks supported by struts near the dropout, are much more able to support heavier loads, than the cantilevered from block. I think the earliest Moulton "shopper" bikes (not the space frame), had integral cantilevered rear and front racks attached to the frame, strong and stable.
Here is a picture of my Moulton, it's a 64 f-frame standard, and you can zoom in and see how the front rack is supported. Below that is a pic of a butcher bike I downloaded off the net. I would bet that the butcher bike can hold a lot of load. I would also bet that would be a ***** to pedal. But here's the thing. The moment arm on a Brompton block is small and until the block breaks or snaps off the ride will be the same. In terms of stability, loads on the Brompton block will act the same as loads held by stronger set-ups. They are all supported off the frame. They will all ride similarly. The block is just as stable, till it breaks or the tension screw at the tops pulls out
or it snaps. The block works because the moment arm is small. The shoppers will have larger moment arms on the frames.
Moulton space frame racks are supported similarly as the f frame.
