Quote:

Will the stock cables on the america work with the speedmaster handleabrs and risers when fitted on an america?



Yes... and then some.

I have America cables and the SM's risers plus aftermarket handlebars that come up around 2" higher than the stock SM handlebars (which are flat) on my SM.
So, assuming that the SM and the America have the same base on which the risers are attached (the English name for it escapes me) then you should be left with an extra 2-4 inches of cable in each case.

Bedouin. Blessed are those eyes that have seen more roads than any man! (Homer).