diff --git a/Makefile b/Makefile
index 0f8351d2c..24dc88c67 100644
--- a/Makefile
+++ b/Makefile
@@ -83,6 +83,7 @@ $(B_DIR)/lib/ultra/os/resetglobalintmask.o: OPT_LVL := -O1
 $(B_DIR)/lib/ultra/os/setthreadpri.o: OPT_LVL := -O1
 $(B_DIR)/lib/ultra/os/startthread.o: OPT_LVL := -O1
 $(B_DIR)/lib/ultra/os/stopthread.o: OPT_LVL := -O1
+$(B_DIR)/lib/ultra/os/stoptimer.o: OPT_LVL := -O1
 $(B_DIR)/lib/ultra/os/thread.o: OPT_LVL := -O1
 $(B_DIR)/lib/ultra/os/yieldthread.o: OPT_LVL := -O1
 
diff --git a/src/game/data/data_003dc0.c b/src/game/data/data_003dc0.c
index 346485a82..41753bcc7 100644
--- a/src/game/data/data_003dc0.c
+++ b/src/game/data/data_003dc0.c
@@ -2274,7 +2274,7 @@ u32 var80060890 = 0x00000000;
 u32 var80060894 = 0x00000000;
 u32 var80060898 = 0x00000000;
 u32 var8006089c = 0x00000000;
-u32 __osTimerList = (u32) &var8009c760;
+OSTimer *__osTimerList = &var8009c760;
 u32 var800608a4 = 0x00000000;
 u32 var800608a8 = 0x00000000;
 u32 var800608ac = 0x00000000;
diff --git a/src/gvars/gvars.c b/src/gvars/gvars.c
index 044bf49f9..1accdab10 100644
--- a/src/gvars/gvars.c
+++ b/src/gvars/gvars.c
@@ -14080,14 +14080,7 @@ u32 var8009c750 = 0;
 u32 var8009c754 = 0;
 u32 var8009c758 = 0;
 u32 var8009c75c = 0;
-u32 var8009c760 = 0;
-u32 var8009c764 = 0;
-u32 var8009c768 = 0;
-u32 var8009c76c = 0;
-u32 var8009c770 = 0;
-u32 var8009c774 = 0;
-u32 var8009c778 = 0;
-u32 var8009c77c = 0;
+OSTimer var8009c760 = {0};
 u32 var8009c780 = 0;
 u32 var8009c784 = 0;
 u32 var8009c788 = 0;
diff --git a/src/include/game/data/data_000000.h b/src/include/game/data/data_000000.h
index 8ade08b94..e3f43ddbb 100644
--- a/src/include/game/data/data_000000.h
+++ b/src/include/game/data/data_000000.h
@@ -183,6 +183,7 @@ extern u32 var80060190;
 extern u32 var800601b0;
 extern u32 var80060340;
 extern u32 var80060368;
+extern OSTimer *__osTimerList;
 extern __OSViContext var800608b0[2];
 extern __OSViContext *__osViCurr;
 extern __OSViContext *__osViNext;
diff --git a/src/include/gvars/gvars.h b/src/include/gvars/gvars.h
index c8430dea5..ff16dca00 100644
--- a/src/include/gvars/gvars.h
+++ b/src/include/gvars/gvars.h
@@ -470,7 +470,7 @@ extern u32 var8009c390;
 extern u32 var8009c400;
 extern u32 var8009c650;
 extern u32 __osEventStateTab;
-extern u32 var8009c760;
+extern OSTimer var8009c760;
 extern u32 var8009c780;
 extern u32 var8009c788;
 extern u32 var8009c78c;
diff --git a/src/lib/ultra/os/stoptimer.c b/src/lib/ultra/os/stoptimer.c
index d0731019d..f5cc1b3ae 100644
--- a/src/lib/ultra/os/stoptimer.c
+++ b/src/lib/ultra/os/stoptimer.c
@@ -1,69 +1,33 @@
 #include <libultra_internal.h>
+#include "game/data/data_000000.h"
 
-GLOBAL_ASM(
-glabel osStopTimer
-/*    48a30:	27bdffd0 */ 	addiu	$sp,$sp,-48
-/*    48a34:	afa40030 */ 	sw	$a0,0x30($sp)
-/*    48a38:	8fae0030 */ 	lw	$t6,0x30($sp)
-/*    48a3c:	afbf001c */ 	sw	$ra,0x1c($sp)
-/*    48a40:	afb00018 */ 	sw	$s0,0x18($sp)
-/*    48a44:	8dcf0000 */ 	lw	$t7,0x0($t6)
-/*    48a48:	15e00003 */ 	bnez	$t7,.L00048a58
-/*    48a4c:	00000000 */ 	nop
-/*    48a50:	1000002c */ 	b	.L00048b04
-/*    48a54:	2402ffff */ 	addiu	$v0,$zero,-1
-.L00048a58:
-/*    48a58:	0c01256c */ 	jal	__osDisableInt
-/*    48a5c:	00000000 */ 	nop
-/*    48a60:	8fb80030 */ 	lw	$t8,0x30($sp)
-/*    48a64:	3c088006 */ 	lui	$t0,%hi(__osTimerList)
-/*    48a68:	8d0808a0 */ 	lw	$t0,%lo(__osTimerList)($t0)
-/*    48a6c:	8f190000 */ 	lw	$t9,0x0($t8)
-/*    48a70:	00408025 */ 	or	$s0,$v0,$zero
-/*    48a74:	1328000d */ 	beq	$t9,$t0,.L00048aac
-/*    48a78:	afb90028 */ 	sw	$t9,0x28($sp)
-/*    48a7c:	27290010 */ 	addiu	$t1,$t9,0x10
-/*    48a80:	afa90024 */ 	sw	$t1,0x24($sp)
-/*    48a84:	8d2b0004 */ 	lw	$t3,0x4($t1)
-/*    48a88:	8f0d0014 */ 	lw	$t5,0x14($t8)
-/*    48a8c:	8d2a0000 */ 	lw	$t2,0x0($t1)
-/*    48a90:	8f0c0010 */ 	lw	$t4,0x10($t8)
-/*    48a94:	016d7821 */ 	addu	$t7,$t3,$t5
-/*    48a98:	01ed082b */ 	sltu	$at,$t7,$t5
-/*    48a9c:	002a7021 */ 	addu	$t6,$at,$t2
-/*    48aa0:	01cc7021 */ 	addu	$t6,$t6,$t4
-/*    48aa4:	ad2e0000 */ 	sw	$t6,0x0($t1)
-/*    48aa8:	ad2f0004 */ 	sw	$t7,0x4($t1)
-.L00048aac:
-/*    48aac:	8fa80030 */ 	lw	$t0,0x30($sp)
-/*    48ab0:	3c0f8006 */ 	lui	$t7,%hi(__osTimerList)
-/*    48ab4:	8d190000 */ 	lw	$t9,0x0($t0)
-/*    48ab8:	8d180004 */ 	lw	$t8,0x4($t0)
-/*    48abc:	af190000 */ 	sw	$t9,0x0($t8)
-/*    48ac0:	8faa0030 */ 	lw	$t2,0x30($sp)
-/*    48ac4:	8d4b0004 */ 	lw	$t3,0x4($t2)
-/*    48ac8:	8d4c0000 */ 	lw	$t4,0x0($t2)
-/*    48acc:	ad8b0004 */ 	sw	$t3,0x4($t4)
-/*    48ad0:	8fad0030 */ 	lw	$t5,0x30($sp)
-/*    48ad4:	ada00000 */ 	sw	$zero,0x0($t5)
-/*    48ad8:	8fae0030 */ 	lw	$t6,0x30($sp)
-/*    48adc:	adc00004 */ 	sw	$zero,0x4($t6)
-/*    48ae0:	8def08a0 */ 	lw	$t7,%lo(__osTimerList)($t7)
-/*    48ae4:	8de90000 */ 	lw	$t1,0x0($t7)
-/*    48ae8:	152f0003 */ 	bne	$t1,$t7,.L00048af8
-/*    48aec:	00000000 */ 	nop
-/*    48af0:	0c014620 */ 	jal	__osSetCompare
-/*    48af4:	00002025 */ 	or	$a0,$zero,$zero
-.L00048af8:
-/*    48af8:	0c012588 */ 	jal	__osRestoreInt
-/*    48afc:	02002025 */ 	or	$a0,$s0,$zero
-/*    48b00:	00001025 */ 	or	$v0,$zero,$zero
-.L00048b04:
-/*    48b04:	8fbf001c */ 	lw	$ra,0x1c($sp)
-/*    48b08:	8fb00018 */ 	lw	$s0,0x18($sp)
-/*    48b0c:	27bd0030 */ 	addiu	$sp,$sp,0x30
-/*    48b10:	03e00008 */ 	jr	$ra
-/*    48b14:	00000000 */ 	nop
-/*    48b18:	00000000 */ 	nop
-/*    48b1c:	00000000 */ 	nop
-);
+int osStopTimer(OSTimer *t)
+{
+	register u32 savedMask;
+	OSTimer *timep;
+
+	if (t->next == NULL) {
+		return -1;
+	}
+
+	savedMask = __osDisableInt();
+
+	timep = t->next;
+
+	if (timep != __osTimerList) {
+		timep->remaining += t->remaining;
+	}
+
+	t->prev->next = t->next;
+	t->next->prev = t->prev;
+	t->next = NULL;
+	t->prev = NULL;
+
+	if (__osTimerList->next == __osTimerList) {
+		__osSetCompare(0);
+	}
+
+	__osRestoreInt(savedMask);
+
+	return 0;
+}