You might want to also check  your O2 Sensor. It is quit possible that it is
your fuel pump. Yet, it sounds as if this problem is only happening on WOT
(Wide Open Throttle). This could be for a varity of problem. IE You are
burning oil; Bad sensor.... The list goes on.. Check the sensor per the
Manual. Might save some trouble..

Namaste
Stephen
85 Westy

PS ask me how I know this some time..