Formula390 - Gear Ratio comparisons for 520 and 415 sprockets

	A	B	C	D	E	F	G	H	I	J	L	M	N	O	P	Q	R	S	T	U	V	X
1	Gear Ratios, MPH, & Chain Lengths
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3	520 Chain											415 Chain
4		Front	Rear	Gear Ratio F/R	Gear Ratio R/F	MPH @ 9,500RPM	KPH @ 9,500RPM	MPH @ 10,250RPM	KPH @ 10,250RPM	Chain Links			Front	Rear **	Gear Ratio F/R	Gear Ratio R/F	MPH @ 9,500RPM	KPH @ 9,500RPM	MPH @ 10,250RPM	KPH @ 10,250RPM	Chain Links

5	14T*	14	39	0.359	2.786	109	176	118	189	108		19T	19	49	0.388	2.579	118	190	127	205	136
6		14	40	0.350	2.857	106	171	115	185	110			19	51	0.373	2.684	113	182	122	196	138
7		14	41	0.341	2.929	104	167	112	180	110			19	53	0.358	2.789	109	175	118	189	138
8		14	42	0.333	3.000	101	163	109	176	110			19	55	0.345	2.895	105	169	113	182	140
9		14	43	0.326	3.071	99	159	107	172	110			19	57	0.333	3.000	101	163	109	176	140	Match of Stock Gearing
10		14	44	0.318	3.143	97	156	104	168	112			19	59	0.322	3.105	98	157	106	170	142
11		14	45	0.311	3.214	95	152	102	164	112			19	61	0.311	3.211	95	152	102	164	142
12		14	46	0.304	3.286	93	149	100	161	112
13		14	47	0.298	3.357	91	146	98	157	112		20T	20	49	0.408	2.450	124	200	134	215	136
14		14	48	0.292	3.429	89	143	96	154	114			20	51	0.392	2.550	119	192	129	207	138
15													20	53	0.377	2.650	115	185	124	199	140
16	15T	15	39	0.385	2.600	117	188	126	203	110			20	55	0.364	2.750	111	178	119	192	140
17		15	40	0.375	2.667	113	182	123	198	110			20	57	0.351	2.850	107	172	115	185	142
18		15	41	0.366	2.733	111	179	120	193	110			20	59	0.339	2.950	103	166	111	179	142
19		15	42	0.357	2.800	109	175	117	188	110			20	61	0.328	3.050	100	160	108	173	144
20		15	43	0.349	2.867	106	171	114	184	112
21		15	44	0.341	2.933	104	167	112	180	112		* 14T is NOT recommended as the sprocket is so small that you get a large amount of wear on the slider on the bottom of the swingarm. If not carefully monitored you will wear through this slider and damage your swingarm. Some cart track riders run these tho, so this info is included for completeness
22		15	45	0.333	3.000	101	163	109	176	112	Stock Gearing
23		15	46	0.326	3.067	99	159	107	172	112
24		15	47	0.319	3.133	97	156	105	168	114		** Additional custom rear sprocket sizes possible by special order & additional machining costs
25		15	48	0.313	3.200	95	153	103	165	114
26		15	56	0.268	3.733	81	131	88	141	120	This sprocket is intended for stunt riders, not street riding.
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28	16T	16	39	0.410	2.438	125	201	135	216	110
29		16	40	0.400	2.500	122	195	131	211	110
30		16	41	0.390	2.563	119	191	128	206	110
31		16	42	0.381	2.625	116	186	125	201	112
32		16	43	0.372	2.688	113	182	122	196	112
33		16	44	0.364	2.750	111	178	119	192	112
34		16	45	0.356	2.813	108	174	117	188	112
35		16	46	0.348	2.875	106	170	114	183	114
36		16	47	0.340	2.938	103	166	112	180	114
37		16	48	0.333	3.000	101	163	109	176	114
38		16	56	0.286	3.500	87	140	94	151	120	This sprocket is intended for stunt riders, not street riding.
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