Cant you shift the splitpoint to the left?
And as Fran said... those extra 15 keys are most welcome if you play in Piano mode...
Its something i miss on todays keyboards... allredy 20 years ago on my GEM WX2, i could set my free splitpoints, not only gving me more freedom, but also allowing me to layer up to 16 sounds on my keybaord each with its own range (or split)
a 76 keys board could be perfect to have 2 splits, allowing you to have 2 different sounds for your right hand...