I just did this 22CENTS throttle mod to my bike last night.. Hole mole did it need it:
10x cheaper than the R6 throttle tube.
No need to cut/grind cable housing.
Took me long to sand the PVC cut-out than to disassemble and assemble the whole chebang.
I did crazy glue the "adapter" in place with a few dabs. Nothing that can't be undone.
Even considering stepping up the OD to be close to 40 or+. Atleast now i can reach WOT without having to change my grip - which is really shady when you try to break/rev match.