diff --git a/src/mame/drivers/ninjakun.c b/src/mame/drivers/ninjakun.c
index 59c72f194e5..b390d3e2fe1 100644
--- a/src/mame/drivers/ninjakun.c
+++ b/src/mame/drivers/ninjakun.c
@@ -41,20 +41,6 @@ WRITE8_HANDLER( ninjakun_flipscreen_w );
 WRITE8_HANDLER( ninjakun_paletteram_w );
 
 
-/******************************************************************************/
-
-/* working RAM is shared, but an address line is inverted */
-static UINT8 *shareram;
-
-static WRITE8_HANDLER( shareram_w )
-{
-	shareram[offset^0x400] = data;
-}
-static READ8_HANDLER( shareram_r )
-{
-	return shareram[offset^0x400];
-}
-
 /*******************************************************************************
  0xA000 Read / Write Handlers
 *******************************************************************************/
@@ -100,11 +86,12 @@ static ADDRESS_MAP_START( ninjakun_cpu1_map, ADDRESS_SPACE_PROGRAM, 8 )
 	AM_RANGE(0xa001, 0xa001) AM_READ(input_port_1_r)
 	AM_RANGE(0xa002, 0xa002) AM_READWRITE(ninjakun_io_A002_r, ninjakun_cpu1_io_A002_w)
 	AM_RANGE(0xa003, 0xa003) AM_WRITE(ninjakun_flipscreen_w)
-	AM_RANGE(0xc000, 0xc7ff) AM_READWRITE(MRA8_RAM, ninjakun_fg_videoram_w) AM_BASE(&ninjakun_fg_videoram) AM_SHARE(2)
-	AM_RANGE(0xc800, 0xcfff) AM_READWRITE(ninjakun_bg_videoram_r, ninjakun_bg_videoram_w) AM_BASE(&ninjakun_bg_videoram) AM_SHARE(3)
-    AM_RANGE(0xd000, 0xd7ff) AM_RAM AM_BASE(&spriteram) AM_SHARE(4)
-    AM_RANGE(0xd800, 0xd9ff) AM_READWRITE(MRA8_RAM, ninjakun_paletteram_w) AM_BASE(&paletteram) AM_SHARE(5)
-    AM_RANGE(0xe000, 0xe7ff) AM_RAM AM_BASE(&shareram) AM_SHARE(6)
+	AM_RANGE(0xc000, 0xc7ff) AM_READWRITE(MRA8_RAM, ninjakun_fg_videoram_w) AM_BASE(&ninjakun_fg_videoram) AM_SHARE(1)
+	AM_RANGE(0xc800, 0xcfff) AM_READWRITE(ninjakun_bg_videoram_r, ninjakun_bg_videoram_w) AM_BASE(&ninjakun_bg_videoram) AM_SHARE(2)
+    AM_RANGE(0xd000, 0xd7ff) AM_RAM AM_BASE(&spriteram) AM_SHARE(3)
+    AM_RANGE(0xd800, 0xd9ff) AM_READWRITE(MRA8_RAM, ninjakun_paletteram_w) AM_BASE(&paletteram) AM_SHARE(4)
+    AM_RANGE(0xe000, 0xe3ff) AM_RAM AM_SHARE(5)
+    AM_RANGE(0xe400, 0xe7ff) AM_RAM AM_SHARE(6)
 ADDRESS_MAP_END
 
 static ADDRESS_MAP_START( ninjakun_cpu2_map, ADDRESS_SPACE_PROGRAM, 8 )
@@ -115,11 +102,12 @@ static ADDRESS_MAP_START( ninjakun_cpu2_map, ADDRESS_SPACE_PROGRAM, 8 )
 	AM_RANGE(0xa001, 0xa001) AM_READ(input_port_1_r)
 	AM_RANGE(0xa002, 0xa002) AM_READWRITE(ninjakun_io_A002_r, ninjakun_cpu2_io_A002_w)
 	AM_RANGE(0xa003, 0xa003) AM_WRITE(ninjakun_flipscreen_w)
-	AM_RANGE(0xc000, 0xc7ff) AM_READWRITE(MRA8_RAM, ninjakun_fg_videoram_w) AM_SHARE(2)
-	AM_RANGE(0xc800, 0xcfff) AM_READWRITE(ninjakun_bg_videoram_r, ninjakun_bg_videoram_w) AM_SHARE(3)
-    AM_RANGE(0xd000, 0xd7ff) AM_RAM AM_SHARE(4)
-    AM_RANGE(0xd800, 0xd9ff) AM_READWRITE(MRA8_RAM, ninjakun_paletteram_w) AM_SHARE(5)
-    AM_RANGE(0xe000, 0xe7ff) AM_READWRITE(shareram_r, shareram_w) AM_SHARE(6)
+	AM_RANGE(0xc000, 0xc7ff) AM_READWRITE(MRA8_RAM, ninjakun_fg_videoram_w) AM_SHARE(1)
+	AM_RANGE(0xc800, 0xcfff) AM_READWRITE(ninjakun_bg_videoram_r, ninjakun_bg_videoram_w) AM_SHARE(2)
+    AM_RANGE(0xd000, 0xd7ff) AM_RAM AM_SHARE(3)
+    AM_RANGE(0xd800, 0xd9ff) AM_READWRITE(MRA8_RAM, ninjakun_paletteram_w) AM_SHARE(4)
+    AM_RANGE(0xe000, 0xe3ff) AM_RAM AM_SHARE(6) /* swapped wrt CPU1 */
+    AM_RANGE(0xe400, 0xe7ff) AM_RAM AM_SHARE(5) /* swapped wrt CPU1 */
 ADDRESS_MAP_END
 
 /*******************************************************************************