diff --git a/src/mame/drivers/segas24.c b/src/mame/drivers/segas24.c
index 507856cefda..6434748aacb 100644
--- a/src/mame/drivers/segas24.c
+++ b/src/mame/drivers/segas24.c
@@ -722,8 +722,8 @@ static void reset_bank(void)
 {
 	if (memory_region(REGION_USER1))
 	{
-		memory_set_bankptr(1, memory_region(REGION_USER1) + curbank * 0x40000);
-		memory_set_bankptr(2, memory_region(REGION_USER1) + curbank * 0x40000);
+		memory_set_bank(1, curbank & 15);
+		memory_set_bank(2, curbank & 15);
 	}
 }
 
@@ -1254,6 +1254,15 @@ static NVRAM_HANDLER(system24)
 		mame_fread(file, memory_region(REGION_USER2), 2*track_size);
 }
 
+static MACHINE_START( system24 )
+{
+	if (memory_region(REGION_USER1))
+	{
+		memory_configure_bank(1, 0, 16, memory_region(REGION_USER1), 0x40000);
+		memory_configure_bank(2, 0, 16, memory_region(REGION_USER1), 0x40000);
+	}
+}
+
 static MACHINE_RESET(system24)
 {
 	cpunum_set_input_line(1, INPUT_LINE_HALT, ASSERT_LINE);
@@ -1907,6 +1916,7 @@ static MACHINE_DRIVER_START( system24 )
 	MDRV_SCREEN_VBLANK_TIME(ATTOSECONDS_IN_USEC(100))
 	MDRV_INTERLEAVE(4)
 
+	MDRV_MACHINE_START(system24)
 	MDRV_MACHINE_RESET(system24)
 	MDRV_NVRAM_HANDLER(system24)
 
@@ -1985,7 +1995,7 @@ ROM_START( qrouka )
 	ROM_LOAD16_BYTE( "14485", 0x000000, 0x20000, CRC(fc0085f9) SHA1(0250d1e17e19b541b85198ec4207e55bfbd5c32e) )
 	ROM_LOAD16_BYTE( "14484", 0x000001, 0x20000, CRC(f51c641c) SHA1(3f2fd0be7d58c75e88565393da5e810655413b53) )
 
-	ROM_REGION16_BE( 0x200000, REGION_USER1, 0)
+	ROM_REGION16_BE( 0x400000, REGION_USER1, 0)
 	ROM_LOAD16_BYTE( "14482", 0x000000, 0x80000, CRC(7a13dd97) SHA1(bfe9950d2cd41f3f866520923c1ed7b8da1990ec) )
 	ROM_LOAD16_BYTE( "14483", 0x100000, 0x80000, CRC(f3eb51a0) SHA1(6904830ff5e7aa5f016e115572fb6da678896ede) )
 ROM_END
@@ -2027,7 +2037,7 @@ ROM_START( bnzabros )
 	ROM_LOAD16_BYTE( "epr-12187.ic2", 0x000000, 0x20000, CRC(e83783f3) SHA1(4b3b32df7de85aef9cd77c8a4ffc17e10466b638) )
 	ROM_LOAD16_BYTE( "epr-12186.ic1", 0x000001, 0x20000, CRC(ce76319d) SHA1(0ede61f0700f9161285c768fa97636f0e42b96f8) )
 
-	ROM_REGION16_BE( 0x200000, REGION_USER1, 0)
+	ROM_REGION16_BE( 0x400000, REGION_USER1, 0)
 	ROM_LOAD16_BYTE( "mpr-13188-h.2",  0x000000, 0x80000, CRC(d3802294) SHA1(7608e71e8ef398ac24dbf851994253bca5ace625) )
 	ROM_LOAD16_BYTE( "mpr-13187-h.1",  0x000001, 0x80000, CRC(e3d8c5f7) SHA1(5b1e8646debee2f2ef272ddd3320b0a17192fbbe) )
 	ROM_LOAD16_BYTE( "mpr-13190.4",    0x100000, 0x40000, CRC(0b4df388) SHA1(340478bba82069ab745d6d8703e6801411fd2fc4) )
@@ -2044,7 +2054,7 @@ ROM_START( bnzabrsj )
 	ROM_LOAD16_BYTE( "epr-12187.ic2", 0x000000, 0x20000, CRC(e83783f3) SHA1(4b3b32df7de85aef9cd77c8a4ffc17e10466b638) )
 	ROM_LOAD16_BYTE( "epr-12186.ic1", 0x000001, 0x20000, CRC(ce76319d) SHA1(0ede61f0700f9161285c768fa97636f0e42b96f8) )
 
-	ROM_REGION16_BE( 0x200000, REGION_USER1, 0)
+	ROM_REGION16_BE( 0x400000, REGION_USER1, 0)
 	ROM_LOAD16_BYTE( "mpr-13188-h.2",  0x000000, 0x80000, CRC(d3802294) SHA1(7608e71e8ef398ac24dbf851994253bca5ace625) )
 	ROM_LOAD16_BYTE( "mpr-13187-h.1",  0x000001, 0x80000, CRC(e3d8c5f7) SHA1(5b1e8646debee2f2ef272ddd3320b0a17192fbbe) )
 	ROM_LOAD16_BYTE( "mpr-13190.4",    0x100000, 0x40000, CRC(0b4df388) SHA1(340478bba82069ab745d6d8703e6801411fd2fc4) )
@@ -2217,7 +2227,7 @@ ROM_START( dcclub )
 	ROM_LOAD16_BYTE( "epr13948.bin", 0x000000, 0x20000, CRC(d6a031c8) SHA1(45b7e3cd2c7412e24f547cd4185166199d3938d5) )
 	ROM_LOAD16_BYTE( "epr13947.bin", 0x000001, 0x20000, CRC(7e3cff5e) SHA1(ff8cb776d2491796feeb8892c7e644e590438945) )
 
-	ROM_REGION16_BE( 0x200000, REGION_USER1, 0)
+	ROM_REGION16_BE( 0x400000, REGION_USER1, 0)
 	ROM_LOAD16_BYTE( "epr-15345.2",  0x000000, 0x80000, CRC(d9e120c2) SHA1(b18b76733078d8534c6f0d8950632ab51e6a10ab) )
 	ROM_LOAD16_BYTE( "epr-15344.1",  0x000001, 0x80000, CRC(8f8b9f74) SHA1(de6b923118bea60197547ad016cb5d5e1a8f372b) )
 	ROM_LOAD16_BYTE( "mpr-14097-t.4",0x100000, 0x80000, CRC(4bd74cae) SHA1(5aa90bd5d2b8e2338ef0fe41d1f794e8d51321e1) )
@@ -2229,7 +2239,7 @@ ROM_START( dcclubj )
 	ROM_LOAD16_BYTE( "epr13948.bin", 0x000000, 0x20000, CRC(d6a031c8) SHA1(45b7e3cd2c7412e24f547cd4185166199d3938d5) )
 	ROM_LOAD16_BYTE( "epr13947.bin", 0x000001, 0x20000, CRC(7e3cff5e) SHA1(ff8cb776d2491796feeb8892c7e644e590438945) )
 
-	ROM_REGION16_BE( 0x200000, REGION_USER1, 0)
+	ROM_REGION16_BE( 0x400000, REGION_USER1, 0)
 	ROM_LOAD16_BYTE( "epr-14095a.2", 0x000000, 0x80000, CRC(88d184e9) SHA1(519F3A22E1619DE9D5F13A45B85EBD249EBFA979) )
 	ROM_LOAD16_BYTE( "epr-14094a.1", 0x000001, 0x80000, CRC(7dd2b7d4) SHA1(C7EAF9E2700E0C55F7E867F5CD3FFAA5AAE97956) )
 	ROM_LOAD16_BYTE( "mpr-14097-t.4",0x100000, 0x80000, CRC(4bd74cae) SHA1(5aa90bd5d2b8e2338ef0fe41d1f794e8d51321e1) )