>Hopefully this mythical machinist can find a way to make each sprocket a single piece.

I kinda made reference to that possibility in this thread:
http://www.bonnevilleamerica.com/forums/...p;page=0#179524

That would be the MPB sprocket option, and would depend on the availability of sprockets in the desired dimensions.
Then there's the problem of getting splines broached.
Is there another way?
Dunno.

This duscussinon seems to be focused on replicating the QPD design.
According to what some have said, it appears that that design in turn is based around a Harley belt.
That's good in terms of availability, but is it optimal for this application?
Dunno.

If the belt could be wider and/or pulleys larger, that would contribute a lot to longevity.
Is this possible?
Does it mitigate the downside re: availability?
Dunno, dunno.

I think alternative tooth profiles are worth a look, too.
Goodyear eagle belts use what they call a helical tooth design.
It looks like the tread on a tractor tire.
The helical part comes in because the teeth run onto the sprocket smoothly.
Like the difference between a Borg-Warner T10 & an old Mopar singing 4 speed in reverse gear.
In this analogy, the blackhawk is "spur cut" like the mopar's reverse.

The belt is self-centering as it runs, so flanges are not required.
This could result in an ability to use a wider belt, because the width of the flanges has been saved.
Goodyear distributors sometimes state that they are stronger by virtue of having longer teeth for the same belt width.
I don't know that Goodyear makes this claim, though.

Downsides & potential show stoppers:
Pulleys are scarce & dear.
There may not even be a stock pulley small enough for the front.
The element of economy that's the focus of this thread may be sacrificed.

Said Molly to James, that's a fine motorbike. Richard Thompson