i dont think (at least with triumphs ) that theres much of a curve to worry about , the old Lucas advance /ret mechanical advance was all over in 12 deg (i think will look ) and i doubt it was smoooth , this unit is rated for 10 deg , but its the full advance thats the important bit , it works well (still not been out mind) starts easy (this is where i was expecting problems should there be any) so all in all good , i am running 12v coils and not 6v or the twin end option . I would be interested if any one knows what Lucas rita system operated over , this used 6v coils and im told worked well , and ive been told storys of triumphs back fireing when the ignition was turned on which inturn gave Lucas a problem with its starter motors in the early days.